Mytsac Technical Review

3/2011

Saving costsTurbocompressors in wastewater treatment

Newly developed pumpsMeeting market trendsin the water segment

Prediction of forcesSimulation in a pump sump

EDITORIAL

| Sulzer Technical Review 3/20112

Dear Technology Professionals, Customers, and Partners,

The demand for water is a megatrend that we leverage at Sulzer. Sulzer is a leadingprovider of technology for transportation, production, and treatment of water aswell as for energy generation with hydropower. The completed acquisition of CardoFlow Solutions has established Sulzer as a leading supplier of pumps and relatedequipment in the wastewater market. Our new technologies increase energy effi-ciency and help protect the environment.The articles in the current Sulzer Technical Review (STR) present selected new solu-

tions and technologies for the water market. For example, you will learn that usingturbocompressors instead of positive displacement blowers for aeration in waste-water treatment leads to significant energy and cost savings. In another article, youwill gain insights into the development process of the new SMD water pump forwater transportation and desalination plants.In this issue, you will get to know the processes for the purification of indus trial

wastewater and water quality analysis. Additionally, you will learn more about the coating solutions from Sulzer for hydropower plants and experience how theperformance of hydroelectric power plants can be enhanced.

I hope you enjoy this issue.

Sincerely yours,

Hans-Walter SchläpferCTO Sulzer

Leveraging themegatrend of water

The Sulzer brothers laid the foundations oftoday's company in 1834 in Winterthur,Switzerland. Sulzer is active in the fields ofmachinery, equipment manufacturing, andsurface technology in more than 160 locationsaround the world. Its divisions are globalleaders in their respec tive markets, includingthe oil and gas sector, the hydrocarbonprocessing industry, power generation, pulpand paper, aviation, and the automotiveindustry. Sulzer employs more than 17000professionals who develop innovative newtechnical solutions. These prod ucts and servicesenable Sulzer's customers to achieve sustainedimprovements in their competitive positions. www.sulzer.com

Sulzer PumpsSulzer Pumps offers a variety of centrifugalpumps, ranging from custom-built models tostandardized series. The division's market-leading position reflects its research anddevelopment activities relating to process-oriented materials as well as its reliable service.It serves customers in the oil and gas, hydro -carbon processing, pulp and paper, powergeneration, water distribution and treatmentsectors, as well as other specialized areas. www.sulzerpumps.com

Sulzer MetcoSulzer Metco specializes in thermal-spray andthin-film processes for surface technologyapplications. The division coats and enhancessurfaces, produces materials and equipment,and develops machining processes for specialcomponents. Its customers are active in theaviation and automotive industries, the powergeneration segment, and other specializedmarkets. www.sulzermetco.com

Sulzer ChemtechSulzer Chemtech is the market leader in thefields of process tech nol ogy, separationcolumns, static mixing, and cartridge tech -nologies. The division has sales, engineering,production, and customer service facilitiesthroughout the world that enable it to meet theneeds of its customers in the oil and gas,chemical, petro chemical and plastics industries.www.sulzerchemtech.com

Sulzer Turbo ServicesSulzer Turbo Services is a leading independentprovider of repair and maintenance services forturbomachinery, generators, and motors withexpertise in rotating equipment. The divisionalso manufactures and sells replacement partsfor gas and steam turbines, compressors, generators, and motors. Sulzer Turbo Services’customers are located in the oil and gas, hydro-carbon processing, power generation, transport,mining, and other industrial markets.www.sulzerts.com

Sulzer InnotecThe research and development unit supportsthe development projects of Sulzer's owndivisions as well as projects of industrialcompanies around the world by providingcontract research and special technical services. Sulzer Innotec has considerable expertise inmaterials engineering, surface engineering,fluid technology, as well as in the field ofmechanics. Its core competencies in the area ofcontract research also focus on these traditionaldisciplines. www.sulzerinnotec.com

Sulzer today

On the cover:

Sulzer is a leading full-line supplier of pumps and related equipment to the waterand wastewater industry. Solutions from Sulzer cover the entire water cycle.

CONTENTS

4 News

Exhibitions, Events

Water and Wastewater6 Saving aeration costs

Positive displacement blower vs. turbocompressor

11 Sulzer analogy

Walkers in white water

12 World-class water pumps

Newly developed pumps meet market trends in the water segment

16 Simulation of the flow in a pump sump

Prediction of the dynamic forces acting on a shaft

20 (Dis)Solving the high boiling problem

Treating industrial wastewater

25 Sulzer world

Welcome to Sulzer Chemtech in Rio Grande do Sul

26 Surfaces for longer lifetime and higher energy efficiency

The benefits of thermal-sprayed coatings in water turbines

31 Hydro-generator refurbishment

Upgrading a power station for improved efficiency

34 Water analysis at Sulzer Innotec

Prevention of water-related corrosion

38 Interview

Marcos Koyama, Sulzer Pumps

39 Imprint

3Sulzer Technical Review 3/2011 |

Exhibitions, Events

November 29–December 1, 2011, Barcelona, SpainEuropean Refinery Technology Conferencehttp://ev557.eventive.incisivecms.co.uk/static/homeInformation for Sulzer Chemtech:Giuseppe MoscaPhone +39 02 6672 13 [email protected]

November 29–December 2, 2011, Geneva, SwitzerlandRussian and CUS Refining Conferencehttp://core.theenergyexchange.co.ukInformation for Sulzer Chemtech:Albert HugPhone +7 4967 76 06 [email protected]

November 29–30, 2011, Esslingen, Germany2. ATZ-Fachtagung Reibungsminimierung im Antriebs-strangwww.gabler.de/Veranstaltung/618Information for Sulzer Metco:Nadine PernhardtPhone +41 56 618 82 [email protected]

November 29–December 2, 2011, Las Vegas, NV, USANGWA National Ground Waterhttp://groundwaterexpo.comInformation for Sulzer Pumps:Jim WillisPhone +1 318 742 [email protected]

December 13–15, 2011, Las Vegas, NV, USAPowerGen International 2011www.power-gen.com/index/conference.htmlInformation for Sulzer Pumps:Jim WillisPhone +1 318 742 [email protected] for Sulzer Turbo Services:Stephanie KingPhone +1 713 567 [email protected]

January 24–25, 2012, Stavanger, NorwayProduced Water Management 2012www.teknakurs.noInformation for Sulzer Chemtech:Daniel EggerPhone +41 52 262 50 [email protected]

4353

Scania Euro 6 engine with SUMEBore™ technologyTruck manufacturer Scania debuts its new Euro 6 enginesthat combine innovative technology solutions to radicallyreduce emissions with low fuel consumption. To helpachieve this innovative technology, the cylinder liners of thenew Euro 6 engine are enhanced with Sulzer’s SUMEBore™coating technology to reduce friction, increase fuel efficiency,and improve corrosion and wear resistance.

Martin Lundstedt, Executive Vice President of Sales andMarketing at Scania states, “We are proud of this impressive performance by ourengineers, and we are happy we can now offer it to our customers. We have doneeverything possible to avoid increased fuel consumption.”

Peter Ernst, Head of Automotive Venture SUMEBore at Sulzer Metco adds,“SUMEBore coating solutions have been successfully used for more than ten yearsin various engines, including large series applications. Based on our long-standingexperience and continuing development efforts, we have reached a high standardof technology and reliability. We have now successfully adapted our coating materialsand system engineering developments to the mass production of cylinder liners forthe new Scania engines.”

Sulzer completes acquisition ofCardo Flow Solutions

The announced acquisition of CardoFlow Solutions was completed on July29, 2011. For a total cash considerationof SEK 5.9 billion (CHF 852 million),Sulzer acquired one of the leading sup-pliers of pumps and related equipmentin the attractive wastewater market. Thebusiness has around 1900 employees.

Headquartered in Malmö, Sweden,Cardo Flow Solutions is a full-linesupplier of pumps and related equipmentsuch as lifters, mixers, aerators, compres-sors, control and monitoring equipment,and services for the wastewater market,which accounts for around 90% of sales.

With this acquisition, Sulzer hasentered the highly attractive wastewater

pump market and will become a leadingplayer in it. In addition, Sulzer hasfurther strengthened its global positionas a supplier of pumps and relatedservices in the general industry, includingthe pulp and paper industry.

Water and wastewater has become akey strategic market for Sulzer, account-ing for approximately 16% of annualsales (proforma combined, based on2010 numbers). The wastewater marketoffers growth potential in both matureand emerging markets, driven by long-term trends such as population growth,increasing water consumption, urbaniza -tion, and environmental protection.

The acquisition creates a strongplatform for further growth, driven byglobal geographic expansion and con-tinued technological development ofcomplete pumping solutions, good after-market opportunities by leveragingSulzer’s existing service network, andcross-selling opportunities with thecombined product offering. The acquiredbusinesses will be fully integrated inSulzer Pumps.

4 | Sulzer Technical Review 3/2011

March 11–13, 2012, San Diego, CA, USANPRA Annual Meetingwww.npra.org/meetingsInformation for Sulzer Chemtech:Rodney AlarioPhone +1 281 441 [email protected]

March 12–14, 2012, Weimar, GermanyJahrestreffen der Fachgruppen Fluidverfahrenstechnikand Computational Fluid Dynamicswww.processnet.deInformation for Sulzer Chemtech Mass Transfer Technology:Marc WehrliPhone +41 52 262 67 [email protected] for Sulzer Chemtech Process Technology:Juan HerguijuelaPhone +41 61 486 37 [email protected]

March 27–30, 2012, Cologne, GermanyAnuga Foodtecwww.anugafoodtec.deInformation for Sulzer Chemtech Mixing and Reaction Technology:Andrea SchwarzPhone +41 52 262 51 [email protected] for Sulzer Chemtech Process Technology:Norbert MartinPhone +49 681 6857 [email protected]

April 1–5, 2012, Houston, TX, USAAIChE Spring Meeting www.aiche.org/Conferences/SpringMeeting/index.aspxInformation for Sulzer Chemtech:Mark PillingPhone +1 918 447 [email protected]

Exhibitions, Events

Sulzer opens its first pumps servicecenter in RussiaSulzer Pumps, one of the world's leadingpump companies, is opening its first ser -vice center in Russia. Located in Khimki,Moscow, the new service center will pro-vide repair and retrofit service for indus-trial pumping systems for Russiancustomers and help to strengthen SulzerPumps’ presence in Russia. Operatingone of the largest service networks in theindustry, Sulzer Pumps has more than 60service facilities with experienced special-ists close to customers around the world.

The service center in Moscow was constructed according to Sulzer Pumpsglobal quality standards and meets alllocal industry regulations. The serviceengineers working in the service center

have experience in local refineries andpower stations and have also receivedtraining in, the wide range of SulzerPumps products and capabilities. Theservice center is equipped for repairs,retrofit, and efficiency improvementactivities of existing pumps as well asthe complete packaging of new ones.The service center will also offertrainings to employees of local cus-tomers.

Pratt & Whitney signs agreementwith Sulzer Eldim Pratt & Whitney signed a long term agreement (LTA) with Sulzer Eldim, a SulzerMetco Company, to manu facture critical engine components for the F135, F100, F119,PW4000, PW2000, and V2500 jet engines.


Successful Sulzer Turbo MachineryTechnology DayMore than 70 participants joined theSulzer Turbo Machinery Technology Dayorganized by Sulzer Innotec on Septem-ber 15th in Winterthur, Switzerland.Speakers from Sulzer Innotec, SulzerTurbo Services, Sulzer Metco, EMPA(Swiss Federal Laboratories for MaterialsTesting and Research) and the Swiss Fed-eral Institute of Technology in Zurichshowed outstanding and interesting pre-sentations. The presentations, the discus-

sions during the conference, and the sub-sequent guided tour of Sulzer Innotec,led to many personal contacts and ex-changes of ideas between participantsfrom Sulzer Innotec, partners from indus-try, and associates from the Sulzer divi-sions.

4354| Sulzer Technical Review 3/20116

BS, a product brand within Sulzer Pumps, is synonymous with innovation and well-proven solutions for wastewater collection andtreatment. The company’s competence in wastewater handling has developedover more than 100 years. Today, the com-pany offers one of the most completewastewater technology portfolios in theworld, and its products and solutions

help solve the challenges in municipal, industrial, commercial, and domestic sectors across the world every day. An important ABS strategy is to

provide the wastewater industry withsolutions that reduce both energy con-sumption and carbon footprint andincrease both equipment efficiency andreliability. To achieve these goals, anumber of world firsts in technology

have been launched. It is known as theABS EffeX revolution. The first step ofthis revolution started in 2009 with thelaunch of the ABS EffeX range of sub-mersible sewage pumps XFP with built-in IE3 premium-efficiency motors. Sixmodels in this range provide motorsspanning from 1.3 to 350 kW.In 2010, the medium-speed ABS sub-

mersible mixer XRW with an IE3 perma-

Positive displacement blower vs. turbocompressor

Saving aeration costsAfter comparing the aeration performance of existing positive displacement blowers withthe aeration performance of an ABS turbocompressor HST, the Spanish wastewatertreatment company FACSA achieved significant reductions in energy and maintenancecosts with the turbocompressor.

The picture shows Castellón de la Plana and the Desert de les Palmes Mountains from the air.

WATER AND WASTEWATER

A

Kai Schreiber | CC-BY-SA

nent magnetic motor followed. It gaveusers a total efficiency improvement ofup to 35% compared with other existingmedium-speed mixer designs. Later thisyear, ABS will be introducing two addi-tional world firsts for saving energy andimproving operational processes inwastewater treatment plants (WWTPs).

Outstanding HST turbocompressorsA further range of innovative ABSproducts with proven energy savings,reduced carbon emissions, and lowermaintenance cost is the ABS turbocom-pressor HST series. These turbocompres-sors are used to powerfully aerate waste-water during the treatment processes.Lower life-cycle costs and easy operationare achieved through:• Magnetic bearings—minimal energyloss and no mechanical wear• Integrated design—compressor, motor,frequency converter, and controlcabinet built in; an easy-to-installpackage

• Small footprint—smaller compressorroom, lower building cost• Low installation cost—no externalstarters or controls required. No craneor special foundation needed• System modularity—permits paralleloperation of numerous compressorsallowing tailor-made installations• Compatibility—can operate in parallelwith all types of compressors, whichfacilitates flexible refurbishment

The ABS turbocompressor HST can beconfigured in groups to suit the aeration

requirements. The ABS Master ControlUnit optimizes the compressor operationto match the desired output and controlsthe group of machines just as one wouldcontrol a single unit. This optimizes theoperation of the whole group in termsof output as well as energy consumption.The performance of four ABS turbocom-pressor HST models is presented inFigure 1.

Aeration devours energyThe biggest single cost of running aWWTP is the cost of energy used forrunning motors. This expense is esti -mated at between 15 and 30% of thetotal operational budget. If the energycosts are broken down, 43% derive fromaeration equipment, 33% from pretreat-ment steps, and 24% from dewateringsludge treatment.Because aeration is the biggest energy

consumer, the Spanish WWTP companyFACSA decided to compare the perfor -mance of its existing positive displace-ment blowers for aeration with a high-speed ABS turbocompressor HST 6000to see if a significant saving in energycosts could be achieved with the latter.

Aeration at the WWTPThe study presented in this article, wasperformed at the WWTP of Castellón dela Plana, a city in the Levante region ofSpain 2.The treatment plant is designed for

treating up to 45000 m3 wastewater/dayand has a total power capacity of



1 Graph of pressure (kPa) versus airflow rate (Nm3/h) for four ABSturbocompressor HST models.

2 FACSA’s wastewater treatment plant in Castellón de la Plana,Levante region, Spain.

Airflow rate (Nm3/h)

Pre

ssu

re (

kP

a)

130

120

110

100

90

80

70

60

50

40

30

0 k 2 k 4 k 6 k 8 k 10 k 12 k 14 k 16 k

HST 2500

HST 6000

HST 9000

HST 40

4 Energy consumption of the positive displacement blower.

EUR

Time (h)

00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23

En

erg

y c

on

su

mp

tio

n k

W•h

kW•h

50.00

40.00

30.00

20.00

10.00

4.00

3.73

2.80

1.86

0.83

be used. The operating specificationsand conditions of the selected ABS turbo -compressor HST 6000 are the following: • Design airflow: between 2475 m3/h and 7462 m3/h at standard conditions• Altitude of treatment plant: 0 m (sea level)

• Ambient air temperature: between 0°C and 35°C

• Relative humidity conditions: 50% to 80%

• Pressure increase: 53kPa (inlet pressure: 101325 Pa;outlet pressure: 154325 Pa)

The airflow is regulated by a built-in frequency drive that can vary speed and

torque to accurately and preciselycontrol the air volume and pressure. Itis this that provides significant energysaving at lower speeds.

Energy consumption analysisTo allow correct comparison of bothaeration technologies, one treatment linewas operated with alternating use of thepositive displacement (Roots-type)blower and the magnetic-levitationturbo compressor, after which the ratiokWh/kg BOD5 eliminated was compared. The biochemical oxygen demand or

BOD is the amount of dissolved oxygenneeded by aerobic biological organismsin a body of water to break down organicmaterial present in a given water sampleat certain temperature over a specifictime period. The same concentration ofmixed-liquor suspended sludge (MLSS)was used in both cases to facilitate nor-malizing the results of one technologywith those of the other. The energy con-sumption of both systems was comparedusing an analyzer that had been set upto measure the equipment operatingdata every 15 minutes.

Analysis of maintenance costsThe analysis of maintenance costs ofboth technologies was carried out theo-retically by comparing the preventivemaintenance tasks of both systems. Theexisting positive displacement blowershave a complete log of performed main-tenance. However, such logs do not existfor the ABS turbocompressor HST as ithad only recently been installed in thetreatment plant (summer 2009). Nevertheless, it should be stressed

that since the start-up of the compressorin September 2009, no repair interven-tions have been made. Also, an importantnumber of references exist of plantswhere the compressors have been



3 Energy consumption of the ABS turbocompressor HST 6000.

1370 kW. The plant, built in 1980, hastwo lines of biological treatment withvolumes of 4428 m3 and 5125 m3 respec-tively. Air is supplied through finebubble diffusers by means of 4 positivedisplacement blowers: two blowers for each line. The power of all blowersis 160 kW, with a nominal flow of11238 m3/h for line 1, and 7326 m3/h for line 2 at standard conditions. For this study comparing normal

rotating positive-displacement (Roots-type) blowers to high-speed turbocom-pressors with magnetic-levitation tech-nology, a turbocompressor with a similarcapacity to the existing blowers had to

EUR

Time (h)

00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23

50.00

40.00

30.00

20.00

10.00

4.00

3.73

2.80

1.86

0.83

En

erg

y c

on

su

mp

tio

n k

W•h

kW•h


running numerous years without suffer-ing damage or problems.

Energy consumptionFigures 3 and 4 show results obtainedduring two days where system conditionswere practically identical. As can be seen,the energy consumption of the positivedisplacement blower is higher than thatof the ABS turbocompressor HST. Infigures 5 and 6, the energy consumptionand characteristics of both technologiesare presented. The EUR/day calculationwas done applying an energy cost of0.098 EUR/kWh.Significant results were obtained

when comparing the ratio kWh/kgBOD5 eliminated and the ratio EUR/day.Figure 7, the analysis of variance(ANOVA) results, shows that the averagevalue of kWh/kg BOD5 eliminated usingthe ABS turbocompressor HST(0.86 kWh/kg BOD5 eliminated) is muchlower than the average value whenusing the positive displacement blower(1.23 kWh/kg BOD5 eliminated). Theenergy consumption is lower by0.37 kWh/kg BOD5 eliminated for theABS turbocompressor HST. Figure 8 ofANOVA results shows that the meanEUR/day for the positive displacement

blower (EUR 258/day) is higher than thecost for the ABS turbocompressor(EUR 233/day).

Maintenance costsGiven the functioning principle of theABS turbocompressor HST, the need forpreventive and corrective maintenanceof its mechanical parts is very low underthe correct operating conditions. Consid-ering the maintenance activities listed insystem maintenance manuals, the theo-retical maintenance costs for a period offive years for a worst-case scenario fora positive displacement blower are aboutEUR19318 in 5 years. Displacement blowers require exhaus-

tive control of the bearings lubricatingoil and moving parts in general. To

estimate the maintenance cost of theblower, an approximation was madeincluding the material cost of the main-tenance performed over the years andthe maintenance personnel costs. A ren-ovation, which costs about EUR 8150,has to be performed on the premises of the supplier when 20000 operatinghours has been reached (approximately2.5 operating years). Therefore, totalmaintenance costs for the positive dis-placement blower are about EUR 27468.Additionally, it should be mentioned

that cranes are required to move apositive displacement blower but onlya normal forklift truck is needed to liftan ABS turbocompressor HST.

The ABS turbocompressor HSTsaves energyOn analyzing the data obtained in thisstudy, it can be concluded that the oper-ating costs of an ABS turbocompressorHST are lower than those of a conven-tional positive displacement blower. Thehigher energy efficiency results of theturbocompressor derive from the higheroptimal operating range of the system,which means that small changes inpressure do not increase energy con-sumption as is the case for a normal dis-placement blower. Magnetic bearingtechnology avoids the use of conventionalbearings and the operation of moving


5 Characteristics of the positive displacement blower.

6 Characteristics of the ABS turbocompressor HST 6000.

Positive displacement blower

Variable Mean Minimum Maximum Standard deviation

kWh/kg BOD5 1.1 0.63 1.57 0.306

EUR/day 258.08 210.14 298.08 24.183

Variable Mean Minimum Maximum Standard deviation

kWh/kg BOD5 0.78 0.43 1.47 0.193

EUR/day 233.60 187.01 290.59 24.067

ABS turbocompressor HST 6000

7 ANOVA results for kWh/BOD5 eliminatedfor the ABS turbocompressor HST 6000 andthe positive displacement pump.

1,4

1,2

1,0

0,8

0,6

0,4

0,2

0

kW

h/k

g B

OD

5e

lim

ina

ted



8 ANOVA results of EUR/day for the ABSturbocompressor HST 6000 turbocompressorand the positive displacement pump.

280

270

260

250

240

230

220

210

200

EU

R/d

ay



parts—such as the belt transmissionsystem in a conventional positive dis-placement blower—to save significantenergy.After several months of running both

existing blowers and ABS’s magnetic-levitation turbocompressor, FACSA con-cluded that with the magnetic-levitationtechnology, between 20 and 30% energysavings had been obtained. The ratio ofpower intake divided by the kilogramsof biological oxygen demand BOD5,went down from 1.23kW/kg BOD5 elim-inated to 0.86kW/kg BOD5 eliminated.This means energy savings of EUR 25146per year, taking into account a cost of0.098 EUR/kWh. Additionally, com -paring the maintenance cost of 27468EUR/5 years for the positive displace -ment blower with the preventive andcorrective maintenance cost of 15771EUR/5 years for the ABS turbocompres-sor HST, EUR 11697 is saved using thelatter.

Satisfied participantsAll participants in the comparativestudy described above are very satisfiedwith the results. David Castell, Managerof the WWTP operated by FACSA inCastellón, gives his views.“I’m very satisfied with the operation of the ABS turbocompressor HST6000 9,which achieves scientifically provenenergy savings of 20–30%. As a resultof our energy reduction, I estimate thatour carbon dioxide reduction is now350–400 tonnes of CO2 per year with theturbocompressor. From a maintenancepoint of view, the system has beenrunning for 2 years in Castellón and hasrequired no interventions at all since itsinstallation. Two other major benefits are much

appreciated. The small size and lighter

weight of the ABS turbocompressor HSTmeans that this system is much easierto handle manually than a blower. It canmoved using just an ordinary trolley—no need for a forklift truck. With a newplant, one can build a smaller room forhousing the machine. No cranes or otherheavy lifting equipment are required. Inaddition, the quietness of the ABS tur-bocompressor HST means that regula-tions governing noise are more easilycomplied with. Staff must use protectiveequipment when working with positivedisplacement blowers but not with turbocompressors. This means morecomfortable working conditions forworkers and no complaints from peoplewho live near a WWTP running a turbo -compressor.FACSA now has two ABS turbocom-

pressors HST installed, including theone in Castellón, and I’d certainly beglad to be informed of any new technol-ogy from Sulzer in the future thatimproves the performance of wastewaterprocesses.”The ABS sales engineer for the

Levante region, Juan Luis Alonso, is alsovery pleased.

“We have always been confident thatthe ABS turbocompressors HST seriescould satisfy the demands of our cus-tomers as regards significant energysaving, reduced maintenance costs, andquiet system operation. The success ofthe ABS turbocompressors HST run byFACSA and the publication of their com-parative study has generated a lot ofinterest, which has led to six further ABSturbocompressor aeration systems beinginstalled in the Levante region. Now thattheir high performance has been provedwithout a doubt through our close coop-eration with FACSA, we look forwardto even greater success in the future.”



Bart JanssenCardo Flow Solutions SpainC/Madera, 14–1628522 MadridSpainPhone +34 620 714 721 [email protected]

Tom AlbrechtCardo Flow Solutions FinlandTekniikantie 4 D02150 EspooFinlandPhone +358 50 404 89 [email protected]

9 ABS turbocompressor HST 6000.

Hapalothrix larvaelive in raging waters,where no enemy cancatch them. Six suction cups provide them withfooting there.

In the mid-1990s, Andreas Frutiger, thena water biologist at the Swiss FederalInstitute of Aquatic Science and Technol-ogy (Eawag) in Dübendorf, was lookingfor such “blephs,” as the family of thenet-winged midges (Blepharoceridae) arecalled in researcher slang, in the whitewater of Swiss streams. In contrast tothe assumption that these highly special-ized insects are very rare, Frutiger foundrepresentatives of five different speciesat 400 locations.

more refined. In the middle of each ofthe six body segments, there is a bio-physical vacuum pump in the form ofa suction cup. After the application ofthe suction cup, muscles pull a plungerupwards in fixed tubular pipes madefrom chitin, thereby creating a vacuumin the pipes. The ring-shaped adhesiondiscs at the lower end of the tubularpipe stick unshakably to the surface.

There has also been speculation as tohow the larvae release the suction cupas quickly as possible during theirmovement. Andreas Frutiger solved thismystery in 1998. In the artificial whitewater channel in Dübendorf, he filmedthe larvae as they walked over a glassplate. Thereby, he saw that the animalalready pushed the individual suctioncups further while the plunger was stillat the top of the tubular pipe—and wasthus seemingly still in suction operation.Frutiger ultimately discovered, in theedge of the adhesive disc, a fine notchthat opened like a mouth shortly beforethe end of the adhesion phase: a valvethen flooded the vacuum chamberwithin a split second and quickly endedthe adhesion. This is why the bodysegment can be moved even before theplunger has travelled back to the lowerstart position.

Mobile in all directionsFurther analysis of the video sequencesdemonstrated the wide variety of thissuction cup technique. Starting with therearmost body segment, the animalmoves one suction cup after the otherin a wave-like action. The most commonspecies in Switzerland, Liponeura cineras-cens minor, which is found up to 2300

meters above sea level, only requires oneto two seconds for a cycle of all sixsuction cups, and can thereby travel upto five centimeters in a minute. In orderto be able to move sideways, the larvaemove some suction cups across theirbody axis. And, if they are in a particularhurry, they can release several suctioncups at the same time and swing theirfront or rear parts to the side at an angle.Some blephs even have a “reverse gear”that they can select if they unexpectedlycome across a weak flow, and want toget back into fast-moving water asquickly as possible.

But why go to all this trouble in theraging mountain stream when there isusually calmer water only a few metersaway? With this specialization in extreme-ly strong currents, the blephs have con-quered an ecological niche where theyare relatively safe from predators andfrom food competitors. If the currentreduces with decreasing water levels,they detach themselves from their sup-porting rock and let themselves becarried along downstream until theyfind more lively water, where they imme-diately connect themselves to a rockagain with their suction cups.Herbert Cerutti

SULZER ANALOGY

Walkers in white water

Despite the foaming water, the larvae a speciesof a net-winged midge stroll over the rocks.

One would think that the place where the mountain stream thundersdown from the cliffs high above and dances foaming over the rockswould be no place for living organisms. However, larvae of a net-wingedmidge stroll about here on the slippery rocks, like some kind of micro-cow grazing on a lawn of algae.

4355 11Sulzer Technical Review 3/2011 |

Biophysical vacuum pumpBlephs have been studied for more thanone hundred years in the Alps and inthe Rocky Mountains. The solution tothe mystery as to how the larvae moveabout in the raging water is really fasci-nating: They attach themselves to theslippery rock surface with a row ofsuction cups. Squids and cuttlefish alsomake use of adhesion through suctioncups; these are pressed flat on contactand thereby stick to smooth surfaces dueto the negative pressure. What theblephs have invented, however, is much

© A. Frutiger | Eawag – aquatic research

© Verastuchelova | Dreamstime.com


f all water on earth, only 2.5% is not salty, and two-thirds of this freshwater is locked up inice caps and glaciers 1. Of the remainingapprox.0.8% (ca. one-third of 2.5%), one-fifth is in remote, inaccessible areas or

Newly developed pumps meet market trends in the water segment

World-class water pumpsTransportation and treatment of water are essential tasks in many industries, andwater is a vital resource for all life on the planet. As the result of targeted productdevelopment for the water segment, Sulzer Pumps, a leader in pump design andmanufacture, has recently introduced two pump ranges for the applications watertransportation and desalination. State-of-the-art design and manufacturing processesmake these pumps stand out due to their high efficiency and easy maintenance.


can not be used easily because it appears as seasonal rainfall in monsoonal deluges and floods. The world’s totalfreshwater reserves are estimated ataround 35million km3. Total global withdrawals of water

amount to about 3700km3 annually—asmall fraction of the estimated reserve.Even though water is the most widelyoccurring substance on earth, the ever-increasing demand for water for sanita-tion, drinking, manufacturing, leisure,

Sulzer is a specialistin transporting

large volumes ofwater over long

distances and highgeodetic heights.

© Darren Bradley | Dreamstime.com

O



2 The pump rangewas developed atthe product designcenter in Winterthur(CH) in close cooper-ation with Sulzer’sglobal manu facturinglocations. State-of-the-art 3D tools including computa-tional fluid dynamics(CFD) for hydraulicdesign were used forthe design process.

3 Finite elementanalysis (FEA) wasused during the

design process toensure mechanical

integrity.

1 Distribution of earths’s water.

Total global water

2.50% Freshwater0.93% Saline groundwater0.07% Saline lakes96.50% Oceans

Freshwater

1.30% Surface water andother freshwater

30.10% Groundwater68.60% Glaciers and

ice caps

Surface water andother freshwater

0.44% Atmospheric andbiological water

0.46% Rivers2.53% Swamps and

marshes3.52% Soil moisture20.00% Lakes73.05% Ice and snow

Source: Igor Shiklomanov’s chapter “World fresh water resources” in Peter H. Gleick (editor), 1993, Water in Crisis: A Guide to the World’s Fresh Water Resources.

and agriculture requires enormous effort to manage and optimize water usage andto minimize the environmental impact of water consumption.

Specialized in water transportationAgriculture and industry are the twolargest users of the world’s freshwaterresources, consuming 70% and 20%respectively. Municipalities account forthe remaining 10%. According to a studyby the International Water ManagementInstitute (IWMI), more than 1.2 billionpeople, one-fifth of the world’s popula-tion, live in areas of physical waterscarcity. For a further 1.6 billion people,water scarcity has economic reasons,with lack of investment or insufficienthuman capacity making it impossible tosatisfy the water demand.Lack of clean water supplies and

sanitation remain major problems inmany parts of the world. The water

sector needs significant investment and funding for water and sanitation.With two new pump ranges specificallydeveloped for water transportation anddesalination, Sulzer is able to supportthe growth of the water market in twoimportant areas. Sulzer Pumps has been specialized in

delivering pumps for transporting largevolumes of water over long distancesand high geodetic heights. Based on itshydraulic knowledge, the division hasrecently developed a new range ofsingle-stage, double-flow, axially splitpumps for water applications—includingwater transportation, municipal watertreatment and distribution systems,desalination plants, and circulationpumps in power plants. Compact in design, these new pumps

are specifically developed to provide thehigh performance and reliability typicallyrequired by water applications.

Optimization supports development Automatic optimization tools played animportant role in the development ofthese new SMD pumps. The pump rangewas developed at the product designcenter in Winterthur (CH) in close coop-eration with Sulzer’s global manufactur-ing locations. State-of-the-art 3D toolsincluding computational fluid dynamics(CFD) 2 for hydraulic design and finiteelement analysis (FEA) 3 to ensuremechanical integrity were used for thedesign process. The results were validated through

model and prototype testing. This pro-cedure made it possible to integrate thedifferent analysis tools much faster andbetter. It also improved control of thefull production chain, resulting in aninnovative design that permits theoptimum hydraulic fit for each dutypoint. This improvement ensures lowerenergy consumption and optimizedhydraulic performance over a widerange of flows.

High level of standardizationTo provide a very high level of standard-ization of the new range, hydrauliccoverage was ensured using standardizedpower levels instead of the traditionalapproach of using standard sizes andhydraulics of chosen specific speeds.While the new range offers 43 hydraulic

designs based on 20 different casingswith two or three impellers per casing,the new approach to hydraulic coveragehas drastically reduced the number ofstandard parts to only three standardizedshaft diameters, sealing systems, andbearing housings. Using such an approach, each pump

size requires a specific hydraulic design;whereas it is not possible to use a specificstandard speed to systematize thesedesigns. The high number of hydraulicdesigns required called for a new andfaster design process. Sulzer Pumpsinvested significant development effortin coupling an automatic optimizationtool with its proprietary hydraulicdesign tools for impellers and casingsand performance prediction using aReynolds-averaged Navier–Stokes(RANS) CFD code.

Low life-cycle costThrough this automated design process,the new pump range meets the highexpectations regarding suction per -formance and efficiency while havingvery compact hydraulic water passages.In addition, the innovative volute andcutwater designs dramatically reducepressure pulsations, shaft and bearingvibration levels, and mechanical stresses.The compact hydraulic dimensions—incombination with the low number ofparts—lead to a cost-effective manu -facturing process and to a reduction inproduct and inventory costs.Sulzer completed extensive model

testing to verify the performance of thesenew hydraulic designs. Because this val-idation was on the critical path of thedevelopment process, model pumpswere produced using rapid prototypingmethods. Acrylic windows in the modelsallowed the observation of cavitationdevelopment as a function of the netpositive suction head available (NPSHa).NPSHa describes the margin between thepressure at the inlet of the pump andthe vapor pressure. The relation of incip-ient cavitation and NPSHa is an importantquality measure for a pump. Because thecavitation was observable through thewindows, it was possible to determinethe NPSH required to avoid cavitationerosion for different impeller materials.

At the same time, dynamic and staticcomponents of the axial and radial loads,as well as suction and dischargepressures were measured to verify safeperformance of the pumps in their fulloperating range. Thanks to the robustmechanical design, the new pump offerslow vibration levels and a bearing lifeof over 100000 hours, which results inlower life-cycle cost 4.

Ensuring mechanical integrityFinite element analysis (FEA) was usedto check the mechanical integrity of thenew range of pumps. This analysisincluded several aspects of the pumpdesign. • Stress levels in the casing and thebolting of the pump during normaloperation and for the maximum allow-able working pressure, as experiencedduring the hydro test

• Analysis of the axial split flangesealing and the internal leakage atmaximum working pressure

• Natural frequencies of the entirepump and its bearing housings as wellas deformation of the casing in thevarious mode shapes.

Particular attention was given to thepackaging design, especially to thepump and drive baseplate. The designof the packaging is executed in 3D usinga parametric approach, which allows forfast response in designing the completepackage specific to each order 5. It alsoallows for analysis of the mechanicalintegrity of the package using finiteelements in calculating the natural fre-quencies of the baseplate. Depending on the hydraulic configu-

ration, the new SMD pump can handleflow rates of up to 16000 m3/h anddeliver heads of up to 260 m. Sulzer’s use of fully 3D design and

associated modern numerical tools forhydraulic and mechanical design werecrucial in developing this new range ofcompact pumps without compromisingefficiency or suction performance. Thesenew designs, together with the reducednumber of standard parts, make thisrange of single-stage, double-flow; axiallysplit pumps a competitive choice inwater applications in terms of both costand performance.



4 Thanks to the robust mechanical design, the new pump offers lowvibration levels and a bearing life of over 100000 hours, which resultsin lower life-cycle cost.

5 The standard SMD package consists of foundation rails for themotor and a separate base plate for the pump, or a combined baseplate for pump and motor.

6 The new MBN-RO multistage ring section pump has specialsuction impeller for low NPSHr, as well as high-quality castimpellers and stage casings for better efficiency.


Production of drinking water In addition to water transportation, pro-duction of fresh water is a mostimportant field in the water segment.Sulzer Pumps is a full-range supplier ofhighly efficient pumps for seawaterdesalination plants using reverse osmosis(RO) or multieffect distillation (MED).Reverse osmosis is a membrane filtrationmethod used to remove larger moleculesand ions from solutions by pressurizingthe fluid on one side of a selectivemembrane. The solute is retained on thepressurized side whereas the puresolvent passes through the membrane.This process is widely used to purifydrinking water from seawater byremoving the salt and other substancesfrom the water.The reverse osmosis process requires

high pressure, and, moreover, it requiresreliable equipment, as the plants gener-ally operate around the clock. Often,these plants provide water to industrialinstallations, e.g., mines, or human set-tlements in areas where no other fresh-water resources are available.

Designed for high pressureThe newly developed MBN/MBN-ROring section multistage pumps 6 havebeen specifically designed for the high-pressure and high-efficiency pumpingapplications in small-to-mediumseawater reverse osmosis plants 7. TheMBN-RO addresses the special need fora high-pressure pump for the reverseosmosis and desalination markets. It

covers flow ranges up to 1100m3/h andhandles pressures up to 90bar.Its improved hydraulic performance

makes it suitable for any other high-pressure application with clean liquids.Particularly its high efficiency, a keyrequirement in the desalination market,is an exceptional feature of the newpump range. The MBN-RO range is manufactured

in duplex or superduplex as standardmaterials for a variety of seawater qual-ities to avoid pitting and crevicecorrosion. By using the same improvedlow-NPSH impellers for every stage, thepump becomes highly modular, and itssimplicity allows for ease maintenance.Main wear parts, such as mechanicalseals or bearings, can be accessedquickly and easily without disassemblingsuction and discharge nozzle.

Ease of maintenanceThe new pump is available for the twospecific speeds nq 29 and nq 33. Specificspeed is a relation of flow rate and headof a pump and describes the geometryof a pump impeller. Low specific-speedradial impellers are generally low-flow/high-head designs, whereas highspecific-speed axial flow impellers arehigh-flow/low-head designs. In order to achieve a modular design

with a minimum number of parts andgood interchangeability, as manycommon components as possible areused for both the nq 29 and nq 33hydraulics 8. Parts such as suction case,

stage case, shaft, bearing parts, andsleeves, as well as some sealing andbalance disk parts are interchangeablebetween both types. Discharge case,diffuser, and impeller are designedspecifically for each specific speed.However, suction and stage impeller usethe same hydraulic and mechanicaldesign, thus reducing manufacturingand inventory cost. With the targeted development of new

pump ranges for water transportationand desalination, Sulzer Pumps hasmoved to the forefront in the market forwater pumps. Sulzer engineers areaware of the specific requirements forthese important applications and havemanaged to develop highly efficient andcost-competitive pumps. At the sametime, these pumps are easy to maintain,thanks to the forward-looking modulardesign that involves a reduced numberof parts.

Philippe DupontSulzer Pumps Ltd.Zürcherstrasse 128404 WinterthurSwitzerlandPhone +41 52 262 67 [email protected]

Jukka-Pekka PeriSulzer Pumps Finland OyP.O. Box 6648601 KotkaFinlandPhone +358 10 234 [email protected]


8 In order to achieve a modular design with a minimum number ofparts and good interchangeability, as many common components aspossible are used for both the nq 29 and nq 33 hydraulics.

7 The MBN-RO addresses the special need for a high-pressurepump for the reverse osmosis and desalination markets.


Computational fluid dynamics (CFD)has been successfully used for manyyears in the development and opti-

mization of pumps. CFD is widely usedfor the prediction of the pump head,power, and efficiency of pump stages.However, exact knowledge of the inflowconditions is necessary in order to be ableto correctly calculate these quantities. Itis therefore also of interest to correctly

predict through CFD the flow conditionsin the sump, from which the verticalpump draws in the water.

The continuous development of numer-ical models, a steady increase in theavailable computing power, and carefulvalidation based on experimental datawith clearly defined boundary conditionsare important factors for the successfulapplication of CFD. The latter is nec -

essary in order to be able to reliablydesign pumps and their hydraulic com-ponents through numerical flow simula-tions.

Calm flow for smooth pump operationLarge vertical pumps, such as those usedfor water supply, for process plants, andin cooling processes of thermal power

Prediction of the dynamic forces acting on a shaft

Simulation of the flow in a pump sumpBy means of flow simulation, engineers from Sulzer Pumps and Sulzer Innotec have been able toshow that a modified pump sump geometry can lead to significantly smoother and uniform inflowat the pump inlet. The radial forces acting on the shaft can therefore be reduced and mainlycentered around the zero point, allowing a significant increase in the lifetime of the bearings.


1 Pump sump witha vertical pump:view of the water

surface (green) andthe streamlines,

colored by velocity(increasing velocity:blue, green, red).

plants, are submerged in a water basin,the so-called pump sump, where theydraw in water 1. These semi-axial flowpumps must be reliable for a wide rangeof operating conditions, from lowpartload to overload. The behavior ofthese vertical pumps is strongly influ-enced by the flow conditions at thepump inlet.

The formation of vortices and high-velocity gradients at the inlet of thepump can negatively affect the perfor -mance and may lead to shaft vibrationsdue to the dynamic radial forces. Thesevibrations can damage the shaft and the bearings and, in the worst case, leadto the failure of these components.Therefore, the industrial standards ofthe Hydraulic Institute1 define thevortex structures and velocity gradientsthat are permissible at the pump inlet.

Up to now, model tests have been per-formed to demonstrate to the customerthat no impermissible flow phenomenaoccur upstream of the pump. As thesetests are very time consuming andexpensive, it is advantageous to comple-ment or replace these experimental testsby numerical flow simulations. Often,

different pump sump configurationshave to be investigated before a favorableflow into the pump can be achieved. Theinvestigations of these variants can becarried out much more efficiently usingnumerical simulations, which reducedevelopment time and costs.

Modeling of the flow conditions fora pump sump on the computerIn order to assess the possibilities andlimits of numerical flow simulation, theoperational behavior of a typical pumpsump with a vertical pump has beenmodeled on the computer. This numericalmodel has been compared with theresults from experiments using a physicalmodel. Engineers have analyzed twopump sump designs to ensure that thenumerical methods also provide thecorrect forecasts under different flowconditions 2 :• The basic geometry, in which the

vortices that occur are impermissibleaccording to the industrial standards.

• Improved geometry, in which novortices occur or only such vorticesoccur that are permissible accordingto the industrial standards.

The occurrence of these vortex struc-tures should be demonstrated by meansof unsteady flow simulations.

The real flow within a pump sumpincludes the free surface of the waterthat may also be deformed by velocitygradients or by the occurrence ofvortices. The modeling of this freesurface by means of CFD is possible butis more complex and thereby requiresmore computer power. This additionaleffort is required because a two-phasesimulation has to be set up that takesthe liquid and the gas phases intoaccount, thus, also, the air above thewater.

In some cases, simpler models can alsoreliably provide the desired information.Therefore, the free water surface isreplaced by a fixed one. However, thissimplification means that deformationsat the water surface can no longer bereproduced.

In addition, to keep the computationalcosts as low as possible, engineers donot model the impeller of the pump—only the outer and inner contours of thepump housing are taken into account. It is assumed that the impeller has no


2 Inflow to the verticalpumps. On the left, theoriginal sump geometrywith distinct vortex structures; on the right, the modified sump geometry with uniformflow.


significant influence on the flow in thepump sump.

Figure 3 compares simulation andexperiment for the basic geometry. Fivevortex structures can be seen in themodel experiments. Two of these can beseen in the photo from the experiments,and they are also indicated in the stream-lines from the simulation: the “floorvortex” and the “side-wall vortex”. Thevortices are submerged and permanent

(type 2 according HI). The more complexsimulation of this geometry with a freesurface could predict four of these. Withthe simpler simulation using a fixedwater surface, on the other hand, it wasnot possible to clearly identify the inter-mittent vortex described as the “back-wall vortex”.

The presentation of the streamlines for the case with the modified geometry4 indicates a much more uniform

flow, which is also confirmed by thepictures from the experiments. Asalready mentioned, no significant vortex structures arise with this config-uration. This behavior can be predictedwith both types of CFD modeling—with and without free surface of thewater.

The results of these simulations showthat the numerical models are able torecognize the different types of vortices


3 Comparison of the vortex structures calculated with CFD and results from the experiments for the basic geometry of the pump sump.


Floor vortex

Back-wall vortex

Uniform inflow

Side-wall vortex

4 Comparison of the vortex structures calculated with CFD and the results from the experiments for the improved geometry of the pump sump.

as defined by the Hydraulic Institute1.The impact of the modification of thegeometry of the sump on the vortex formation is also reflected.

The validation shows that, in the caseof the basic geometry where impermis-sible vortices structures occur, the CFDmodeling with free surface predictsthese better than the simpler methodwith fixed water surface. However, theseslightly more accurate results require asignificantly larger computational effort.For this reason, it would be sufficient inmost cases in industrial practice to carryout the simulation with the moreefficient method with fixed surface.

Determination of the dynamicforces acting on the shaft The impact of pump inflow on radialforces acting on shaft and bearings isalso of interest in pump design. In orderto investigate this, engineers must carryout a transient simulation of the verticalpump with the impeller.

The computational domain onlyincludes the pump without the sumpand begins at the pump inlet. In orderto obtain the correct inflow conditionsinto the impeller in the simulation, engi-neers use the inlet velocity profile froma sump simulation. This information isobtained as described above. For com-parison, a uniform inlet velocity profileis also used.

The forces can be determined byadding the pressures acting on therotating parts of the pump. The spatialdistribution of the force components Fx

and Fy is plotted for one impeller revo-lution. The resulting forces on the shaftduring operation with a uniform velocityprofile at the inlet are shown in figure5.

It can be seen that the forces arelargely centered around the origin, thecenter point of the shaft. The case withan inflow with a non-uniform velocityprofile from a sump simulation is shown

in 6. The resulting forces are, in thiscase, no longer located around the centerpoint of the shaft. The forces areincreased by around a factor of twoagainst the main flow direction. Thismeans that there is a strong dynamicload on the shaft, which may lead to itsfailure or to damage at the bearings.

Fewer model tests thanks to state-of-the-art simulation methodsThanks to state-of-the-art simulationmethods, it is now possible to consider-ably reduce the number of expensivephysical model tests. Numerical flowsimulation is able to predict the vortexstructures and the velocity gradients thatare relevant for the assessment of sumppumps according to industrial standards.

If the inflow profile at the pump inletis transferred into a simulation for theimpeller, the radial forces that act on theshaft can be determined. Coupled flowcalculations (sump and pump internals)have shown even larger forces. It is thuspossible to determine in the designphase whether any impermissibledynamic loads act on the shaft and,thereby, on the bearings.

The precondition for reliable predic-tions from numerical flow simulationsis the thorough validation with experi-mental data, as well as exact knowledgeof the limits of these methods.

Felix A. MuggliSulzer Markets & Technology Ltd.Sulzer InnotecSulzer Allee 258404 WinterthurSwitzerlandPhone +41 52 262 42 [email protected]

Susanne KrügerSulzer Pumps Ltd.Zürcherstrasse 128401 WinterthurSwitzerlandPhone +41 52 262 40 [email protected]

References1 ANSI. Pump Intake Design Standards (ANSI/HI 9.8). Parsippany, New Jersey: Hydraulic Institute, 1998.



5 Spatial distribution of the radial forces acting on the impellerduring an impeller revolution as calculated with CFD for a uniformvelocity profile at the pump inlet.

6 Spatial distribution of the radial forces acting on the impellerduring an impeller revolution as calculated with CFD for a non-uniform inlet velocity profile from a sump simulation.

10000

– 10000 – 5000

0

0

– 5000

5000

Fy (N)– 10000

5000 10000

Fx (N)

Flow fromthe sump

10000

– 10000 – 5000

0

0

Fy (N)– 10000

5000 10000

Fx (N)

Flow fromthe sump

– 5000

5000


Alarge number of pollutants inindustrial wastewater are organicchemicals that are dissolved in

water. These are only biodegradable inthe rarest cases. Therefore, this waste-water cannot be cleaned in a municipalsewage treatment plant together withdomestic wastewater. The substancesoften interfere with the microorganismmetabolism or are even toxic. Such pol-lutants must therefore be removed

before the wastewater is discharged, as,for example, in the case of pollution withorganic solvents.

Depending on the source of the waste-water, the typical concentrations of thesolvents lie in the range of 1–20% byweight. Such concentrations of pollutantsare too low and the calorific value of thewastewater flow is too low for thermaltreatment, which is basically incineration.The requirement for a secondary fuel

would be very high—leading to highcosts and additional environmental pollution.

Wastewater stripperStripping represents a well-proven andeffective method of treating wastewatercontaminated with solvents. In thisprocess, wastewater is fed into the topof a rectification column and steam ispassed through the column from the

Treating industrial wastewater

(Dis)Solving the high boilingproblemSulzer equipment can cost effectively remove pollutants from large wastewater flows.Depending on the boiling points of the pollutants to be removed in relation to that of water,Sulzer recommends either a wastewater stripper or a liquid-liquid extraction unit.

Part of an extraction column on a truck. During the contact of the two liquids in the extraction column, the phenol is transferred from the water to the extract. The latter has a higher affinity for phenol than water.


bottom in the opposite direction. Thissteam can be directly fed from anexternal steam network, but can also begenerated in an evaporator. Figure 1

shows a diagram of this process. Simple wastewater stripping is suitable

for use for all solvents with a lowerboiling point than water and for thosethat form a low boiling azeotrope withwater. The solvent, which will be con-densed as a concentrate at the head ofthe column, accumulates in the vaporphase. The maximum achievable solventconcentration is determined by the ther-modynamic equilibrium and by economicconsiderations. Wastewater that is prac-tically free from solvents can be removedfrom the bottom of the column. After ithas been used for the preheating of thepolluted wastewater flow, it can eitherbe fed into the sewer system or berecycled in the process. The concentrateobtained at the head of the column caneither be treated further, with the solventbeing recycled, or can now be incineratedmore cost efficiently.

If the solvent forms a heterogeneousazeotrope with water, and shows a mis-cibility gap, the decanter presented asan option in Figure 1 will be required.The water phase from the decanter isfed back into the stripping column, asit has a composition similar to the feedand is saturated with the solvent. Theorganic phase can be correspondinglytreated further or be disposed of as aconcentrate.

The costs of this process are mainlydetermined by the thermodynamics ofthe water-solvent mix. Depending on thevapor-liquid equilibrium, a differentwater concentration will result at thehead of the column, and will thereforealso lead to a different energy require-ment for a sufficiently concentrated,

solvent-rich flow. Typical solvents thatcan be removed through direct strippingwithout a decanter are alcohols andketones. A decanter is required for esters,ethers, short-chain hydrocarbons, andother substances that do not mix withwater. This process is also well suitedfor wastewater that is simultaneouslypolluted with several components.

Problem: high boiling substancesIf wastewater is polluted with a chemicalthat has a boiling point above 100°C atatmospheric pressure, the wastewaterstripping process above is of limited use.If the substance forms an azeotrope withwater that has a lower boiling point thanpure water and that has a sufficientlyhigh enrichment, then wastewater strip-ping can be performed with a decanteras described earlier. The solvent canthereby be effectively enriched in the dis-tillate of a stripping column and can beremoved well, despite the high boilingpoint.

If the thermodynamic equilibrium isless favorable, however, direct strippingcannot be used. Phenol, for example, hasa boiling point of 182°C. Although itforms an azeotrope with water, theboiling point of this azeotrope is only99°C with a phenol content of 9% byweight. This almost corresponds withthe solubility of phenol in water at25 °C1. No concentration will take placein wastewater saturated with phenol.Because the boiling point of the azeotropeis very close to that of water, thestripping column will also need to havea very high separation performance.

This would require a high number ofstages and a high reflux ratio. The cor-responding column would therefore behigh and would consume a great amountof energy. Considering the high water

content in the azeotrope, direct strippingis therefore not practical.

Separation is also difficult in the caseof water polluted with acetic acid. Aceticacid has no azeotrope with water andhas a higher boiling point than water, sothat all the water would be removed asa low boiling substance out of the dis-tillate in direct “stripping.” This processwould not be stripping in the true sense,but would be wastewater evaporationand would thereby be extremely energyintensive. Treatment would also bepossible using extractive or entrainer distillation, but both are complicatedand also require a lot of energy.



1 Wastewater stripper with optional decanter,including a wastewater example.

2 Flow diagram of a liquid-liquid extractionunit, including solvent treatment and a waste-water stripper.

FeedAcetic acid/Phenol

Wastewater

Extraction column

Decanter

Extractant recovery

Wastewater stripper

Extractant

Feed (100kg/h)92% Water8% Ethyl acetate

Bottom product (92kg/h)> 99.99% Water

Heat exchanger

Stripping column

Live steam

Vent

Cooling water

Condenser

Decanter

Distillate (8kg/h)> 97% Ethyl acetate< 3% Water

(Concentration figures quoted in % by weight)

1

2

3

4

1 2

3

4

Solution: ExtractionIn such cases, liquid-liquid extractionoffers an elegant solution to the separa-tion problem. This process is based onthe different solubility of a substance—the so-called transfer component—intwo liquids that cannot be mixed witheach other or that can only be partiallymixed. If these two liquids are broughtinto contact with each other, a two-phaseliquid-liquid dispersion results, and thetransfer component divides itself accord-ing to the thermodynamic equilibriumbetween the two liquids.

The liquid that has a higher affinityfor the transfer component—and thattakes these up—is generally describedas the extraction agent, while the liquidphase enriched with the transfer compo-nent is described as the extract. Thedonor phase with depleted transfer com-ponent is called the raffinate. Liquid-liquid extraction is mostly carried out atambient temperature and pressure, sothat no additional energy is required forheating or cooling.

In many cases, ketones, esters, orethers are used as extraction agents forphenol and acetic acid. During thecontact between the two liquids in theextraction column, a material transportof the phenol takes place from the waterto the extraction agent, as the latter hasa higher affinity for the phenol thanwater. The water will thereby becomedepleted of phenol and the extractionagent enriched. At the same time, how -ever, the water will become saturatedwith the extraction agent that is beingused, so that the water itself cannot bedirectly discharged after the extraction.

The extraction stage alone cannotpurify the water, but the componentwith a high boiling point can be removedwithout an evaporation step. The waterthereby takes up another material—theextraction agent. This agent has a lowerboiling point than water and/or formsa low boiling azeotrope, and thereforeit can be simply removed with the strip-ping process described earlier. In somecases, a solvent that is already presentin trace quantities in the feed is used forthe extraction. In this way, no additionalmaterials are brought into the process.

The transfer component—in this case,phenol or acetic acid—must be removedfrom the loaded extraction agent in orderto make the agent reusable for extraction.This is normally carried out in a rectifi-cation unit. Figure 2 shows the basicflow diagram of the complete process.

ComparisonBiodegradable solvents can also beremoved by means of biological waste-water treatment in a sewage treatmentplant. They are, however, mostly recycledfor cost reasons. A comparison of thetwo processes described above, on thebasis of the two flow diagrams, indicatesthat the removal of a high boiling com-

ponent from wastewater using extractionis much more complicated than single-stage stripping. Key factors in anefficient process are the right choice ofthe extraction agent and the operatingconditions of all the connected columnsthat have been adapted to the separationtask.

The extraction agent must havecertain properties: it must not bemiscible with water—or at least be onlyslightly miscible—it must have a highaffinity for the transfer component, andit should be as environmentally friendly


3 Internals of the Kühni-type ECR column.

4 Pilot liquid-liquid extraction columnwith 60mm diameter.



and cost-effective as possible. The ther-modynamic equilibrium of the extractionagent, water, and transfer component arekey determining factors for the energydemand of the complete system, becausemost of the energy is used for solventrecovery in the rectification column afterthe extraction column.

As a last step, the most suitable typeof apparatus must be chosen for eachprocess step. Depending on the originof the wastewater, the pollutant con -centration, volumetric flow rate, andrequired purity can be very different.The optimal column type for the extrac-tion step must be selected according tothese variables. On the one hand, thedecisive factor for the selection is thethermodynamic liquid-liquid equilibri-um, which, together with the solventratio, determines the necessary numberof separation stages.

On the other hand, the concentrationof the transfer component in the feed isof great importance. The physical prop-erties of the liquid phases stronglydepend on the concentration of thetransfer component. This applies todensity, viscosity, and, in particular, tointerfacial tension, which have a greatimpact on the hydrodynamic conditionsin the column. In addition, the flow ratesof the raffinate and extract phase overthe height of the column also changedue to the mass transfer in the extraction


5 Loading of a modular system from Sulzer Chemtech for recovery

of solvents and purification.

column. These changes are often so sig-nificant that the internals of the extractioncolumn have to be adapted to these. Thisis the case when wastewater is pollutedwith 10% or more acetic acid by weight,for example.

The agitated Kühni column type ECRhas proven to be very suitable for appli-cations that require high separation per-formance and great flexibility. Figure 3

shows internals of this type of column,in which the geometry can be changedin each compartment. In this way, it ispossible to compensate for any changesin physical property data and mass flowrates that arise typically in the case oflarge mass transfer. ECR extractioncolumns have already been successfullyused for wastewater with up to 12%phenol by weight and 35% acetic acidby weight. Columns have been builtwith more than 30 theoretical stages.

Columns with structured Sulzer extrac-tion packing type ECP are used for verylarge wastewater flows with throughputsof several 100m3/h. This type of columnis characterized by a high hydrodynamiccapacity but does not allow separationperformances as high as ECR columnsdo. Together with liquid distributorsspecifically adapted to the packings,very efficient processes can be realizedwith these columns, in which largematerial flows can be treated that requireonly moderate separation performance.

Distillation trays are used in thestripper column for the post-treatmentof wastewater, as there is often a largeliquid load in these columns and a two-phase liquid in the upper part. The treat-ment of the extraction agent is oftencarried out in a rectification column withSulzer distillation packing designed forhigh separation performance.

In comparison to biological treatmentof municipal wastewater, industrial

waste water treatment often requires the use of different thermal separationprocesses. The optimal selection of theextraction agent, the type of equipmentthat will be adapted to the task, and theoperational parameters require broadknowledge and experience in all areasof thermal separation technology. Thisis vital in order to be able to combinethe individual unit operations to achievean efficient process. The necessary datafor the design and operation of thesystem is obtained through a comparisonwith reference installations and, in par-ticular, for the extraction step, throughpilot trials in the Sulzer Test Center2.Figure 4 shows a section of a pilot liquid-liquid extraction column in operation.Based on many years of experience, itis thereby possible to find a turnkeysolution to remove many high boilingpollutants from a wastewater flow, asshown in Figures 5 and 6.


Jörg KochSulzer Chemtech Ltd.Gewerbestrasse 28P.O. Box 514123 AllschwilSwitzerlandPhone +41 61 486 37 [email protected]

References1 Smallwood, I.M. Handbook of Organic Solvent Properties.London: Arnold, 1996.

2 Zuber, L. “The Power of Testing.” Sulzer Technical Review2/2011, Winterthur: Sulzer Management Ltd., 2011.

6 3D layout of awastewater stripper in

a Sulzer Chemtechmodular construction.


At work in a plant.

In April 2010, Sulzer Chemtech acquiredCL Engenharia Ltda, a maintenancecompany in Rio Grande do Sul, thesouthernmost state of Brazil.Porto Alegre is the capital of Rio

Grande do Sul and the closest city tothe premises of CL Engenharia. CLEngenharia was founded at the beginningof the 1990s by the father of the latestowners, Jorge Alfredo (since almost thebeginning) and Luiz Alberto Celada(since 2006). Their great-grandparentswere Spaniards with Italian roots whofirst moved to Argentina and thensettled in the neighboring part of Brazil.At the beginning, the company

was operated with approximately 20 employees and rented tools. Itprovided technical services for the repair and maintenance of electrical and mechanical equipment. A few years later, CL Engenharia increased its line ofbusiness by starting to offer mainte nance

and mechanical assembly, primarily tocompanies within the petrochemicalcomplex in Triunfo, in the neighborhoodof Porto Alegre. The headquarter of CL Engenharia was relocated to Triunfoin 1999.The business success of CL Engenharia

shows that the founder had the rightidea and testifies the tenacity andperserverance typical of Jorge and all his employees. Today, CL Engenharia isa recognized local specialist in the main-tenance of vessel internals, welding,modification, and repairs as well as themaintenance and fabrication of heatexchangers and boilers, mainly in RioGrande do Sul but also across the wholecountry. As an example, the companyhas several long-term maintenance con-

tracts in Triunfo for servicing and main-taining various mechanical systems andindustrial boilers.The former owners as well as all other

employees (approx. 300) are now part of the North and South Americanregional organization of Tower FieldServices, and the premises serve as basisto support the presence of SulzerChemtech in Brazil.

SULZER WORLD

Welcome to Sulzer Chemtech in Rio Grande do Sul

Vessel fabrication at Sulzer Chemtech in Rio Grande do Sul.

Sulzer strengthens its Tower Field Services activities with the acquisitionand integration of CL Engenharia Ltda. Through local specialists, Sulzer now offers maintenance of vessel internals, welding, modification,and repairs as well as maintenance and fabrication of heat exchangersand boilers throughout Brazil from our base in Rio Grande do Sul.

4359 25Sulzer Technical Review 3/2011 |

Jorge and Luiz CeladaFabio Secchi


ccording to the World Energy Out-look 2010 report of the Interna-tional Energy Agency, the world-

wide primary energy demand will be35% higher in 2035 than in 2008 as aresult of increasing world populationand increasing prosperity, particularly in

the emerging markets. However, on thewhole, the proportion of demand for different primary energy sources willchange. The study predicts an overallincrease in oil consumption of onlyabout 20%—well below the average predicted rise in demand.

Gas, hydro, and other renewableenergies will grow in all countries 1.The share of renewable energies for electricity production will increase from 19% in 2008 to 32% in 2035. But,after the Fukushima nuclear disaster inMarch 2011 and the declaration of a

The benefits of thermal-sprayed coatings in water turbines

Surfaces for longer life and higher energy efficiencyHydroelectric power contributes importantly towards the expansion of renewable energysources. Sulzer Metco coatings protect many water turbine components from erosionand corrosion damage; thus, they contribute to a safe, economical, and environmentallyfriendly energy supply.

Dam of a hydroelectricstorage power plant

in the Alps.


© Prochasson Frederic | Dreamstime.com

A


nuclear phase-out by some of the leadingindustrial nations, it can be assumed thatthe growth of renewable energies willoccur much faster than was predicted in2010.One of the most environmentally

friendly forms of energy production ishydropower. Water-powered electricutility plants can be differentiatedbetween run-of-the-river power stations,reservoir power stations (e.g., dams),and pumped-storage hydropowerstations. Run-of-the-river hydroelectricpower plants are built directly in theriver and produce energy continuously.Pumped-storage hydropower plants canalso be used for energy storage.Energy storage is nowadays an impor-

tant factor for on-demand electricity con-sumption. Germany currently has aninstalled pumped-storage capacity ofabout 7 GW with a daily operatingcapacity of 4 to 8 hours. This results in a remarkable overall storage capacityof about 40 GWh. Future projects willnotably increase that capacity. Anotheradvantage of pumped-storage powerplants is that they are highly efficient,i.e., the excess electrical energy can be stored with an overall efficiency of 80%.Hydropower plants, particularly the

turbines, face efficiency losses from corrosion and wear by erosion (hydro -abrasion, fluid erosion and cavitationerosion) that depends on the type ofpower plant, the turbine design (Francis,Kaplan, or Pelton) 2, and the specificoperating conditions (e.g., the corrosivepotential and the sand, gravel, and stonedebris in the water) 3.The first hydroelectric power plant

was built in 1880 in Northumberland,England. The high wear on the bladescaused by corrosion and erosion required,

at that time, that the turbines be manu-factured from expensive high-alloy steelcastings. The technology of today’spower plants differs significantly fromthat in Northumberland. Tools such ascomputer modeling optimize componentdesigns to minimize cavitation. On theother hand, the overall stress loads onturbine components have risen.This is caused not least by ambitions

to achieve greater profitability, exploitgreater heads (water pressures andvelocities), and expand weirs into inac-cessible mountain regions, such as theHimalayas and the Andes. It is alsocaused by the desire to build faster-rotating, small turbines as well as large“monster” turbines and power plants inrivers that are contaminated with sandand chemicals.As the expectations of service life,

maintenance intervals, and turbine efficiency are constantly rising, wear protection for power plant componentsis of increasing importance.

Longer lifetime of water turbines with coating solutions from Sulzer MetcoThe names Sulzer and Metco have beenclosely associated with the field ofhydropower for a long time. As early asthe 1930s, Metco applied steel, chromiumsteel, bronze, and zinc coatings toFrancis runners to investigate the per-formance of these coatings in cavitationtests.In Germany and Austria during the

1960s, abrasion tests were performed onKaplan machines using Metcoloy 2 (13%chromium steel wire) coatings at the Innpower plants. Later, these coatings wereused successfully in the field. Combustionwire spray has become a standardcoating technology in the turbinebusiness and has since been used suc-


– 600 – 300 0 300 600 900 1200 1500

1 Projected growth in primary energy consumption by technologyfrom 2008 to 2035. (Source: OECD / IEA World Energy Outlook 2010)

2 Conditions of use for water turbines.(Source: Catalog Sulzer Hydro / Sulzer Escher Wyss)

OECD China Rest of the world

50.00

30.00

20.00

15.00

10.00

7.00

5.00

3.00

2.00

1.50

1.00

0.70

0.50

0.30

0.20

0.15

0.10

0.05

Po

we

r (M

W)

Water fall (m)

10.00

5.00

2.50

1.00

0.50

0.25

Wa

ter

flo

w (

m3/s

)

2 3 5 7 10 20 30 50 70 100 150 300 500

0.03 0.05 0.1

CATPIT

KRTKaplan

RRT

Bevel Gear BulbTurbine

and Compact Kaplan

Francis

Compact Francis

Pelton

Compact Pelton

Coal

Oil

Gas

Nuclear

Hydro

Other renewables

Millions tonnes of oil equivalent (Mtoe)

3 Cavitation damage on a Francis turbine.

5 A Kaplan turbine blade, coated with Sulzer Metco SUME™Turb.

cessfully in almost all types of waterturbines. Compared to the formerly usedstandard technology—weld buildup—the primary benefits were much shorterprocessing time and reduced detrimentalthermal effects to the base material andcomponents.

Successful launchToward the end of the 1980s, Metco introduced its new DiamondJet™ high-velocity oxygen fuel spray process(HVOF). This new technology wassuited for the workshop and wasadequate for everyday use due to itssimple design. The first early attemptson sleeves were very promising, and sothe range of parts to which coatings suchas tungsten carbide materials (of typeWCCoCr) were applied expanded veryquickly. The component lifetimesachieved using these new HVOF coatingsexceeded the boldest expectations.Thus, material erosion was reduced

by a factor of 50 from that of turbinesteel (1.4313). The transition from the very thick layers that were commonat that time (e.g., 10 mm thick wire combustion-sprayed Metcoloy 2) to thethinner, but also more erosion-resistant,HVOF-sprayed carbide coatings wasthen initiated. Diagram 4 shows a com-parison of the wear characteristics ofvarious surface coatings. The dominantposition of the HVOF process withWCCoCr as the coating material isevident.

Groundbreaking coating developmentIn the 1990s, Sulzer Innotec, SulzerMetco, and Sulzer Hydro collaboratedto develop groundbreaking coatings andmodels for hydroturbine applications.An example is the development of

the SUME™Turb coating especially forKaplan turbine blades 5. This WCCoCrcoating is applied with the Sulzer MetcoDiamondJet HVOF gun. The coatingthickness is 400µm or less.Additionally, a large percentage of

Francis and Pelton turbines parts thatare in contact with the water are coated.Some components, such as labyrinthseals on Francis machines, are constructedfor optimal ease of coating. In themajority of cases, the coated componentscan be used without further treatment.

Proven materialsFigure 6 provides an overview of thecommonly used coating systems for thedifferent types of water turbines.Typical standard Sulzer Metco

WCCoCr materials that have proventheir value in this area—consider-ing load condition, the specific appli-cation, and the HVOF system used—are Diamalloy 5849, Amdry 5843, SulzerMetco 5847, Woka 3652, Woka 3653, andSUMETurb. Despite practically identicalchemical composition, these powdermaterials have different particle shapes,morphologies, particle size distributions,primary carbide sizes, and bulk densities.Therewith, they differ in production andmanufacturing parameters and thestarting raw materials used.These differences are clearly visible in

wear test results 7. However, these differences are not noticeable throughthe usual hardness test performed forquality assurance. Thus, it becomes evident that in the

water turbine industry high-velocityoxygen fuel spray (in the workshop,with DiamondJet, WokaStar, or WokaJetguns) or wire combustion spray (in theworkshop or on-site with 14E, 16E or



Duk | CC-BY

4 Erosion resistance of different materials and coating systems.

Erosion resistance relative to X5 Cr Ni 13 4

Co

ati

ng

0 50 100 150 200 250 300 350

DJ Hybrid WCCoCr

Jet-Kote WCCoCr

Weld overlay

Oxide 2

Oxide 1

Hard chrome

Wire arc

Stellite 6

80 m/s 62 m/s

50 mm



6 Selection of the most important applications for thermal-sprayed coatings in water turbines.

Kaplan turbine

Component Coated area Coating Wear mechanism

Discharge ring Partial or entire dischargering

• Wire combustion-sprayed 15 mm thick Metcoloy 2

Erosion(hydroabrasion, fluid erosion)

Kaplan blade Partial or entire blade • HVOF 0.4 mm thick WCCoCr• wire combustion-sprayed 5 mm thick Metcoloy 2

Guide vanering

Between planar surface and draft tube liner

• Wire combustion-sprayed 5 mm thick Metcoloy 2

Protective sleeve

2-part sealing elements • HVOF 0.3 mm thick WCCoCr• wire combustion-sprayed Metcoloy 2

Seal area, abrasive wear

Radial bearing Applied to new or repairedcomponents

• Wire combustion-sprayed Sprababbitt A

Sliding wearCrank Slide bearing area • Wire combustion-

sprayed Sprasteel-LS

Crank pin Slide bearing area • Wire combustion-sprayed Sprasteel-LS

Francis turbineCheek plate Complete area

HVOF / WCCoCrErosion (hydroabrasion,fluid erosion)

Guide vane Complete guide vane, also disc and face sideseals

Turbine cover Clearance and labyrintharea, wear ring area

Runner wheel Clearance and labyrintharea, runner inlet channel

Pelton turbinePelton bucket Inside and edge HVOF / WCCoCr

Erosion(hydroabrasion, fluid erosion)

Pelton needle Area subject to wear • HVOF / WCCoCr• Plasma / Cr2 O3

Needle spear Area subject to wear • Wire combustion-sprayed Metcoloy 2 / Sprabronze

Sliding wear

Nozzle tip Entire internal contour

HVOF / WCCoCr Erosive and abrasive wear

Nozzle tip insert ring

Area subject to wear

Jet deflector Area subject to wear

Jet deflectingcover

Area subject to wear

EGD-K) are mainly used. Plasma spray,yet another thermal spray process, haslargely lost importance in this areawhereas it was previously used to applywear coatings to needles, nozzles, andFrancis turbine parts.

Development supportAs with most mechanical parts, a generalrecommendation of a suitable coatingsolution cannot be made without detailedanalysis of the application. Dependingon the design of the machine, its specificoperating parameters, and its specificservice conditions, extensive differencesin the dominant or overlapping wearmechanisms can prevail. In the worst case, it can happen that

the stresses mutually reinforce oneanother. In general, however, it can beassumed that wear due to hydroabrasion,corrosion, and cavitation erosion increas-es with the flow velocity, the quantityof entrained solids, and the corrosionpotential of the fluid. The wear in oper-ation depends on factors such as size,shape, and hardness of the solidparticles. Therefore, predictable limitsfor individual materials cannot be spec-ified.Because the wear behavior of a

material cannot be predicted by itssimple physical and mechanical charac-teristics such as hardness, elastic modulus,and tensile strength, it becomes necessaryto employ specialized wear tests. Whilephenomenological tests are used todetermine the basic wear behavior ofmaterials under well-defined loadingconditions, application-specific tests aredesigned for specific conditions andcomponents. The results of these testscan usually be transferred directly to an application1.

Together with its partner SulzerInnotec, Sulzer Metco is fully equippedwith test benches both for phenomeno-logical studies as well as for customer-and application-specific coating develop-ment. In detail, the following testfacilities are currently available:• Cavitation/erosion test per ASTMG32-03

• Abrasion test bench per ASTM G65(dry sand rubber wheel)

• Abrasion/corrosion test (modified ASTM G65 test)

• Salt-spray test per ASTM B117, alsosuitable for ASTM G85, ASTM B368,ASTM G43, and ASTM D2247

• Current-potential measurement• GE erosion test per GE50TF121• Taber abraser per ASTM G75• Two-body block-on-ring test (wear of friction pairs under sliding friction)

• Water-jet erosion testSulzer Metco offers its coating applicationexpertise and its expertise analyzing

data generated from the above-men-tioned test beds to develop customizedapplications. It can be determined, forexample, which of the available coatingsystems is best suited for a given stress.For example, a special cavitation test bedis used at Sulzer Metco 8 especially toassess the cavitation of HVOF-sprayedcoatings.Through close and proprietary coop-

eration, Sulzer Metco provides its cus-tomers the ability to select the bestsolution from a number of existingcoatings or to further develop an existingcoating to fulfill the customer’s specificturbine requirements. Thus, hydrotur-bines can operate for longer periods ateven greater efficiencies, further con-tributing to effectiveness of these renew-able energy resources.

AcknowledgmentThe authors thank Hans Rinnergschwent-ner for his valuable contribution to thisarticle.



Hans-Michael HöhleSulzer Metco Europe GmbHSpreestrasse 265451 KelsterbachGermanyPhone +49 172 6212 [email protected]

Montia C. Nestler Sulzer Metco (US) Inc.1101 Prospect Ave.Westbury, NY 11590-0201USAPhone +1 516 338 [email protected]

7 WCCoCr coating wear behavior.

8 Cavitation test rig at Sulzer Metco.

Black/grey: Sintered WCCoCrBlue: Various Sulzer Metco HVOF coatingsRest: Various WCCoCr coatings sprayed with other market-available systems

and materialsGWF: Erosion resistance (water jet erosion) under all impact anglesWF 12°: Erosion resistance (water jet erosion) at grazing angle of 12°BoR3: Abrasion resistance (3-body wear test)

Re

lati

ve

we

ar

be

ha

vio

r (%

of

du

ple

x)

References1 Kränzler, Thomas: “Ensuring product quality through

customized materials tests – Classification of materials”;Sulzer Technical Review 1/2010

120

110

100

90

80

70

60

50

40

30

20

10

0

BoR3

WF 12º

GWF


Sulzer Technical Review 3/2011 | 314361

Hydro-generator insulation systemshave a finite life and generallyneed to be rewound after

50 years—although some insulationsystems have lasted much longer. Whenthe generator is due to be rewound, itis an opportune time to consider increas-ing the rated output. Modern insulatingmaterials, although thinner than ever,are capable of withstanding greaterdielectric stress and higher operatingtemperatures than the materials used inthe original stator and rotor windings.Figure 1 shows how a stator coil froman older machine (1950s) was redesignedto give improved performance andextended insulation life.

Thinner insulation—increased outputAs can be seen in figure 1, the thinnerinsulation of today’s insulating systemsallows more space for copper, whichreduces the resistance of the statorwinding. As a result, the winding willrun cooler and permit a small increasein output. The higher temperature ratingof today’s insulation system permitshigher operating temperatures and there-fore increased outputs. When a generator is upgraded, the

operator needs to have design perfor-mance calculations for the new ratedoutput of the generator. These calcula-tions include operating curves, excitationcurves, reactances, and time constants,

etc. Before the output can be increased,a design model needs to be producedfor the original machine design andoriginal rated output using data availablefrom the power station operator andfrom site measurements. This designmodel has to accurately reflect theelectromechanical and thermodynamicperformance of the original machinewhen compared with original perfor-mance data and the station’s operatingrecords for temperature rise and excita-tion current at specific outputs.

Improved performanceOnce the design model has beenproduced and verified, it is used toevaluate improvements in the stator coildesign and determine the temperaturerises when operated at the new ratedoutput. The design program generatesthe performance data required by theoperator. If the refurbishment includesreplacement of the stator core, there isan opportunity to use a lower-loss gradeof magnetic steel than that used in theoriginal machine construction. Whenchanging stator core material, one mustconsider the increase in excitationrequirements of the lower-loss grade ofsteel. Occasionally, it is possible to improve

performance by some adjustment of thestator slot dimensions, although it is sur-

Upgrading a power station for improved efficiency

Hydro-generator refurbishmentSince 1882, when one of the first AC hydroelectric power stations was built with a capacity of 12.5kW, the number of stations has grown very significantly not only in number but also in capacity. Today, for example, the Three Gorges power station has a capacity of 22500MW.Many power stations were built in the first half of the 20th century, and several stations have been in operation for over 100 years. Although the dams are relatively unchanged, the efficiency improvements in turbines have resulted in increased shaft power and, therefore, increased generation output.

1 Drawing of coilredesign for a

1950s generator.

Poor fit of coil in slot

Too much space between coil sides

Original copper size withmodern insulation

10% increase in copper X-section

25% increase in conductor insulation

11% increase in slot wall insulation

New copper size withenhanced insulation


prising how good many original slotdesigns were, given the methods ofdesign calculation available at the timeof construction. Improvement in thecontrol of stray losses can be achievedby changing the method of stator coiltransposition in order to reduce circulat-ing current losses, or by changingwinding covers to a non-magneticmaterial. Generally, any increase in generator

output requires an increase in rotor exci-tation current. This increases the totallosses within the machine with aresultant increase in stator and rotoroperating temperatures.

Upgrade at the Barron Gorge powerstationAn example of a hydro-generator rewindand upgrade occurred at the BarronGorge power station, which is operatedwithin a World Heritage tropical forestsite in Queensland, Australia 2, 3. The power station was constructed inthe early 1960s and went into service in1963. The underground station was originally constructed with two 30MWvertical 10-pole generators driven byFrancis turbines. In 2009, Sulzer rewound and up -

graded the first generator from 30 MWto 35 MW, and Sulzer is currently finishing the rewind and upgrade of thesecond generator. The original workscope was to rewind the generator stator,reinsulate the rotor, and, if necessary,rewind the exciter. When the statorwinding was stripped and a stator coretest conducted, deficiencies in the corewere identified that necessitated thecore’s replacement. The customer agreedto an amended work scope and program,including a replacement core. When the core was stripped, further

deficiencies in the stator case were iden-tified, which were rectified during thelead time for the replacement stator core.This work included the manufacture andfitting of new building dovetail bars,core bolts, and clamp plate heel system.

The stator coil redesign slightly increasedthe cross-sectional area of the conductor(3.12 %), and the improved method ofstator coil transposition reduced thestray losses. This change enabled thegenerator output to be increased by16.67 % within the 65 °C temperaturerise limits specified in the tender require-ments. The insulation system passed theIEEE 400 hr voltage endurance test.Figure 4 shows the generator floor, andfigure 5 shows a station section model. One significant change in the generator

design was in the method of control ofcirculating current losses in the stator

2 Entrance to the underground generators in the Barron Gorge power stationin Queensland, Australia.

3 Barron Gorge.

4 Generator floor at Barron Gorge. 5 Station section model.


winding. The original manufacturer’stransposition consisted of two 180°twists of the top and bottom conductorstack one-quarter of the way and three-quarters of the way through each phase.The design also swapped and twistedthe top and bottom halves of the conductor stack halfway through the phase. The new transposition systemhad double top-top or bottom-bottomstrand transpositions at all coil connec-tions.

10% reduction in lossesThe replacement core laminationsegments were manufactured from agrade of magnetic steel that provides a10% reduction in losses over the materialused in the original machine construction.The rotor field coils were stripped andreinsulated with Class F insulating mate-rials, as was the DC exciter. The DCexciter was redesigned to enable anincrease in field forcing from 150% to200%.

The site rewind was managed by ourlabour from UK and Australia. TheSulzer Dowding & Mills branch inBrendale, Brisbane, Australia, rewoundthe field coils and exciter. The locationof the site within this unique WorldHeritage tropical forest site introducedsome additional environmental chal-lenges for the project management.

Enhanced generator efficiencyThe stages of the rewind can be seen infigure 6 a–h. It was possible to enhancethe efficiency of the generator from97.99% before the rewind to 98.09% afterthe rewind. The losses for the generatorbefore and after rewind are shown infigure 7. The first rewind was completed

within the revised program as agreedwith the customer. The second rewindis currently due to be completed fourweeks ahead of schedule. The tests atthe completion of the first rewind metthe customer’s requirements, and, duringthe heavy rains earlier this year, therewound generator ran continuously atmaximum output.


John Allen Sulzer Dowding & MillsCamp Hill, BordesleyBirmingham, B12 0JJUnited KingdomPhone +44 121 766 [email protected]


7 Losses for the generator before and afterthe rewind.

6 Stages of the rewind.

a) Original winding data recording b) Original winding stripped

c) Rebuilding and consolidating new core d) All new coils inserted

e) Stator winding connected f) Stator winding completed

g) Reinsulated rotor h) Generator assembly

Generator Original UpgradedMVA 33.33 39.00

MW 30.00 35.00

Fixed losses kW kW

Friction, windage, and iron losses 361.00 361.00

NL excitation losses 24.70 24.70

Variable losses

FL excitation losses 60.30 78.10

FL stator and stray losses 173.00 219.70

Total losses 616.00 683.50

Efficiency 97.99 98.09

Stator temperature rise 46 °C 53°C

Rotor temperature rise 43 °C 55°C


The specialists of Sulzer Innotechave been working for more than40 years investigating water quality

and its impact on materials. Through many years of practical

experience, Sulzer Innotec has acquiredsignificant experience in the field ofwater-related corrosion and cases of damage, and it passes on this know-how

to customers and to workgroups for the specifications of water-conductingequipment and systems. At present, the water laboratory of

Sulzer Innotec operates as a contract lab-oratory for industrial and private cus-tomers. Hundreds of water andglycol-water samples from various appli-cations are analyzed here every year.

Among the applications examined arewaste incineration plants, industrial fac-tories with heating and cooling circuits,cooling towers, air washers and air-con-ditioning plants, as well as heating sys-tems in houses. This vast amount of product knowl-

edge is, therefore, one of the strengths ofSulzer Innotec. Clients are advised indi-

Prevention of water-related corrosion

Water analysis at Sulzer Innotec

Water is the ideal medium for a variety of purposes thanks to its high heat capacity, environmentalfriendliness, and easy availability. However, if the water quality is ignored, damage can occur due tocorrosion, formation of deposits, or growth of microorganisms. Damage totaling billions of dollarsoccurs worldwide from water-related corrosion every year.

1 Photo of a cooling systemused in industry.


vidually and receive support in solvingtheir problems—with services rangingfrom normal standard analyses, throughon-site measurements, to customer-specific analyses with the developmentof specific analytical procedures.Through preventative water analysis,

Sulzer Innotec has been able to avert massive damage to various facilities andequipment in many cases over recentyears, thereby saving millions of dollarsin costs 1.

Water as the cause of pitting corrosionAt low temperatures, the presence ofwater is necessary for the corrosion ofmetals. Due to the special properties of water (dipole moment, oxygen solubil-ity), dissolved ions (such as chlorides andsulfates) can come into contact with thesurface of a metal together with oxygenand cause corrosion. Much of the corrosion damage that

occurs could be prevented or delayed ifconditioned water of a suitable composi-tion and quality were used and if its qual-ity were monitored regularly. Variouscases of damage that have been investi-gated in recent years have been tracedback to the use of unsuitable water. In one of the cases of damage exam-

ined by Sulzer Innotec, a piece of pipehad been delivered with various smallholes in it. The pipe was part of a cooling

system in a refinery. As the operation ofthe refinery had been interrupted for along period due to the damage, a loss ofseveral CHF 100000 had resulted. The pipe was made of so-called

stainless steel. High-alloy stainless steelshave a very thin, but nevertheless protec-tive passive layer, which consists mainlyof chromium oxides. Despite this protec-tive layer, the surface of the pipe was partially rusted and showed signs of localized corrosion attack (pitting).The examination of the material re-

vealed that the material had the correctspecifications and had been properlyprocessed. A material defect could there-fore be eliminated as the cause of thedamage. In order to find the cause of thecorrosion, the customer was asked to pro-vide a water sample from the affectedcooling system. A high level of chloridewas subsequently found in this watersample. Stainless steel is very susceptibleto chloride attack because chloride lo-cally destroys the passive layer and thuscauses pitting. If, as a result, even more chloride is ac-

cumulated at the said location, a localarea arises that is no longer protected bya passive layer. This area is now moresusceptible to corrosive attack. Differences in concentration, potential

differences, or even a reduced pH valueat the location of the attack promote

pitting corrosion and lead to a fastergrowth of the holes. Small holes can thenappear in the steel, even on passivatedstainless steel 2. If the water quality hadbeen checked in advance, it would havebecome clear at the planning stage thatthis steel was unsuitable for the waterquality used 3. The costs of the water analyses and the

consultation on the selection of the mostsuitable material and the conditioning of the cooling water would have onlyamounted to a fraction of the damagecosts.


2 Piping made from high-alloy stainless steel with clearly visible pitting corrosion.

3 A check of thewater quality can indicate whether the steel being used is suitable.

100µm

100µm1mm

100µm


Problems due to high microbio -logical contamination of the waterDamage to plants can be triggered notonly by inorganic constituents in thewater, but also by microorganisms. If thewater has a high level of microbiologicalcontamination, biofouling can occurthrough the formation of biofilms.Biofilms consist of a mucus layer (film) inwhich microorganisms are embedded. The film offers the microorganisms a

mechanical anchor and protection fromexternal chemical and physical in -fluences, and it allows them to adaptthemselves to changes in the environ-mental conditions. In this way, the micro -organisms can survive extreme pH andtemperature fluctuations, pollutants (e.g.,bactericides), and even UV radiation and lack of nutrients.

This robustness hinders the elimina-tion of the biofilms. The economic dam-age caused by biofouling is enormous.For example, the flow of water in pipescan be reduced significantly, and thepipes can even clog in extreme cases. In the case of cargo ships, a biofilm of

only one-tenth of a millimeter on the hullcan reduce the ship's speed by severalpercent through the increased friction.This also results in increased fuel con-sumption.Another danger posed by water with

a high level of biological contaminationis microbiologically induced corrosion(MIC). In MIC, the aggressive metabolicproducts of bacteria lead to corrosive attack of the metal. Sulfate-reducing bacteria (SRB) prevail, and they form aggressive sulfides. In the case of passivematerials, chlorides are also necessary for MIC attack to occur. These chloridesdestroy the passive layer locally. Biofilmsare a frequent source of MIC. Recent estimates suggest that at least 20% ofcorrosion damage is either triggered, orpromoted by MIC. As it is difficult to eliminate biofilms,

preventative measures are highly recom-mended. Therefore, Sulzer Innotec offersbacterial count checks in order to be ableto detect an increased microbiologicalcontamination in the water in time 4.Biofouling or MIC can then be preventedby appropriate countermeasures.

Water as a cause of microbiologicallyinduced corrosionA perforated CuNi pipe was delivered to Sulzer Innotec for the investigation ofcorrosion damage to a condenser of acooling unit. The condenser was cooledwith river water. Neither a material defect nor a manufacturing error couldbe found in the initial investigation. In

order to find the cause of the damage, awater sample was also examined. The chemical analysis of the water

sample revealed no anomaly, and neitherthe pH value nor the chloride contentcould be identified as being responsiblefor the corrosion. Further investigationrevealed a strong microbiological con-tamination of the river water. As the sample had been delivered in non-sterilecontainers, however, the sampling had to be repeated for verification using sterile containers. A sample of the river water was taken

before and after it passed through thecondenser. A microbiological investiga-tion was also carried out directly on thecorroded tube. A very high level of micro-biological contamination was found inboth water samples. The sample takenafter the water had passed through theheat exchanger also indicated agglomer-ations of bacteria, which is a clear indica-tion of the formation of biofilms. Asignificant quantity of microorganismswere also detected at the corrosion loca-tions by means of direct microbiologicalanalysis. After further investigations, micro -

biologically induced corrosion (MIC) wasdefinitively confirmed as the mechanismfor the damage. Recommendations toprevent biofilms and corrosion were pro-vided to the customer. Further corrosionof the system could therefore be success-fully avoided. Without the analyticalwork of Sulzer Innotec, the piping of the condenser would have had to be replaced at regular intervals 5.

Hazard of Legionella in cooling towers and water systemsIn addition to the hazards of corrosionand fouling, microorganisms can alsopresent problems for human health.


4 Cultivated microorganisms on an agar plate.


10 mm

Legionella 6 are particularly critical, andrepresent a significant hazard in air con-ditioning plants, ventilation systems, andcooling towers in particular.

Legionella are rod-shaped, gram-nega -tive bacteria that belong to the family Legionellaceae. They have one or more flagella with which they can movearound and occur in both freshwater and salt water, where a temperature of25–50°C is a precondition. Water standingfor long periods (stagnant conditions)also promotes their growth.Forty-eight species and 70 serogroups

of legionella are currently known, all

being classified as harmful to humanhealth. The most important type forhuman illness is the pathogen legionellapneumophila, as this can cause Legion-naires’ disease or the so-called “PontiacFever.” In healthy people, Legionnaires’disease is fatal in approximately 15% ofcases, while mortality can be up to 70%for people with compromised immunesystems.The Legionnaires’ disease was first

identified in 1976 at a meeting of the USwar veterans association, the “AmericanLegion State Convention,” from which italso received its name. At this meeting,

181 people became ill with severe pneu-monia at this meeting. All of the affectedpeople were either participants in thewar veterans’ conference, or were guestsin the same hotel. As a result of this epidemic, the US

American health authorities began inves-tigating the causes, and, in 1978, wereable to identify the responsible legionellapneumophila pathogen, which had estab-lished itself in the air conditioning sys-tem of the hotel. Other epidemics wereretrospectively attributed to the same legionella pneumophila pathogen, as wellas the Pontiac Fever, which was de-scribed for the first time in Pontiac in1968. Through the routine testing of water

for legionella, Sulzer Innotec has been ableto identify a number of cases of legionellainfestations in the last few years and hasthereby been able to prevent illness out-breaks. With the early detection of legionella, the affected system can becleaned and be refilled with fresh water,so as to ensure safe operation.


Roger HäusermannSulzer Markets and Technology Ltd.Sulzer InnotecSulzer-Allee 258404 WinterthurSwitzerlandPhone +41 52 262 21 [email protected]

5 CuNi pipe with clearly visible local attacks of microbiologically induced corrosion (MIC).

6 Legionella colonies growing on an agar plate illuminated with ultraviolet light.

Photo credit: CDC / James Gathany

50 mm


10 mm

| Sulzer Technical Review 3/2011

Sulzer has been building centrifugalpumps since 1857. What are the cur-rent core competencies of Sulzer inthe water and wastewater business?To answer that, I have to go back in time. Since the beginning, we have had the unique ability to develop pumps optimized for specific appli -cations, as, for example, for water trans-port. In the water transport business, it is very important that the equipmentis highly efficient and robust and that it can provide reliable service for manyyears. Additionally, when desalination

became commercially feasible, weinvested in one technology—calledreverse osmosis—which today is therelevant technology for water desalina-tion. We entered this business at thebeginning, in the mid-1990s, and ourtalent to engineer highly efficient andreliable pumps allowed us to develop astrong presence there. We were one of the first to use con-

figured pumps in the desalinationbusiness and are now one of the marketleaders. We recently also entered themarket of large thermal desalination

plants (multieffect distillation, MED).This technology is now at a level tocompete with advantages against theMSF (multistage flashing) technology. In 2005, Sulzer acquired Johnston, a

major player in the municipal business.Johnston has 100 years of experience inmaking vertical pumps. Already withthis acquisition, we had an extensiveproduct range and the talent to engineerproducts to solve unique challenges.

How does Cardo Flow Solutions enrich the product offering?Sulzer was still not active in a big portionof the market because the wastewatermarket demanded submersible pumps.Sulzer did not have this technology andwe only participated in the wastewatermarket with tailormade products. Wehave been looking for a way to penetratethis market for several years. Now with the acquisition of Cardo

Flow Solutions and its product brandABS, we have integrated a company thatis one of the leading companies in themarket. It designs very efficient products,and it has a complete product portfoliospecifically for the wastewater market,

such as aeration products, pumps, andagitators.

Where do you see great growth potential in the water and in thewastewater business?The water and wastewater business isbig and stable. There is approximately5% growth per year on a global basis.Having solutions for both markets givesus very good opportunities to grow inthe Americas and in Asia. Wastewateris driven by infrastructure projects,which are abundant in these geographicalareas.In Europe, the Middle East, and North

Africa we expect to grow with desali -nation and water pipeline projects inaddition to wastewater.

Sulzer Pumps manufactures standardand configured pumps, as well as engineered pumps—i.e., pumps thatare optimized for a specific applica-tion. Which approach prevails in thewater and wastewater business?Standard pumps are already fully con-figured and are mass produced. Config-ured pumps are something in-between

INTERVIEW

Marcos Koyama: “Our equipment is efficient and reliable”

Sulzer Pumps is a leading supplier of centrifugalpumps. The product line ranges from standardizedpumps through configured pumps to complex customized pumps. We spoke with Marcos Koyama—head of the Water and Wastewater business seg-ment—about Sulzer pump technology and new oppor-tunities after the acquisition of Cardo Flow Solutions.

436338

a standard and an engineered pump.The pumps are configured using differentstandard elements such as casings,impellers, materials, accessories, etc., butyou need to have experience to be ableto do a smart configuration for a specificapplication. Engineered pumps are specially

designed pumps for a specific application.Before the acquisition of Cardo FlowSolutions, Sulzer only had configuredand engineered pumps. Coming back to your question: In

general terms, engineered productsaccount for ca. 15% of the market interms of value. Looking at the specificsegments, it varies significantly. Forexample, in the municipal wastewaterbusiness, where ABS is strong, nearly allpumps are standard pumps. In themunicipal and industrial water business,a mix between configured products anda smaller portion of standard productsis required.

How can customers from Sulzer andfrom the former Cardo Flow Solu-tions profit from the now extendedoffering?Our product portfolio now contains allproducts from Sulzer, Johnston, and ABS.Together, we have more than 300 yearsof experience and know-how. Our cus-tomers can profit from our presence withproducts and service all over the world. We can cover all processes in the water

industry—from production throughtransportation to freshwater treatmentand decontamination. We have a hugespectrum of products and services tomeet all their requirements. Furthermore,we are committed to continuous improve-ment to being even more energy efficient.

Are there any technological or legislative developments to whichyou are paying increased attention?We take water for granted. However, ahuge infrastructure is needed to bringwater to your tap. Water is essential forlife and also for industry. There are no

major industrial processes that can takeplace without water. The growing awareness of the envi-

ronment leads to stronger regulations interms of water quality, water treatment,and energy efficiency. These develop-ments lead to major investments. Forexample, no products that have contactwith drinking water should contaminatethe drinking water. For that reason, theymust be made of certified materials. Moreover, energy consumption is the

biggest expense for our customers.Therefore, increased efficiency andreduced consumption is very importantfor them. On top of that, a lot of energy is dis-

sipated from pressurized water. Whenthe pressure of water in the pipe is toohigh to use directly in a process, thepressure must be reduced. We arelooking at technologies with which wemay be able to recover this energy.

One last question: How long is thelifetime of a pump, and what is usu-ally done when the lifetime is over?Customers specify the lifetime expectancyof a pump—typically 25–30 years. But,to be honest, the expectation is that itwill last longer. For example, a few yearsago, I got an inquiry from Argentinafrom a customer that owned a pumpthat had been operating since 1929! There is always an increase in demand

for water. When a customer needs topump more water through a givenpipeline, we have the competence toredesign the pumping infrastructure.Usually, the strategy is to keep as muchas possible of the given infrastructureand only replace where necessary. Interview: Gabriel Barroso

Marcos Koyamastudied in Brazil in the state of São Paulo. He specializedin mechanics with two majors—machine design andproduction processes—and he holds a masters degree inindustrial business management. He has been workingin the pump industry for 35 years, and he has been work-ing for Sulzer in various positions and locations for 29 years. He moved to Switzerland six years ago, and his current position is Head of Business Segment Waterand Wastewater.

The Sulzer Technical Review (STR) is acustomer magazine produced by theSulzer Corporation. It is publishedperiodically in English and German and annually in Chinese. The articles are also available at: www.sulzer.com/str

3/201193rd year of the STRISSN 1660-9042

PublisherSulzer Management Ltd.P.O. Box8401 Winterthur, Switzerland

Editor-in-ChiefGabriel Barroso [email protected]

Editorial AssistantLaura [email protected]

Advisory BoardMia ClaseliusRalf GerdesThomas GerlachHans-Michael HöhleErnst LutzClaudia PrögerHans-Walter SchläpferHeinz SchmidShaun West

TranslationsInterserv AG, Zürich

Design Concept Partner & Partner AG, Winterthur

DesignTypografisches Atelier Felix Muntwyler, Winterthur

PrintersMattenbach AG, Winterthur

© November 2011

Reprints of articles and illustrations arepermitted subject to the prior approval of the editor.

The Sulzer Technical Review (STR) hasbeen compiled according to the bestknowledge and belief of Sulzer Manage-ment Ltd. and the authors. However,Sulzer Management Ltd. and the authorscannot assume any responsibility for thequality of the information, and make norepresentations or warranties, explicit orimplied, as to the accuracy or complete-ness of the information contained in thispublication.

Circulation: 16000 copies.

Magno Satin 135g/m2

from sustainably managed forests.

For readers in the United States of America onlyThe Sulzer Technical Review is published periodically bySulzer Management Ltd., P.O. Box, 8401Winterthur,Switzerland. Periodicals postage paid at Folcroft, PA, by US Mail Agent – La Poste, 700 Carpenters Crossing,Folcroft PA19032.Postmaster: Please send address changes to SulzerTechnical Review, P.O.Box 202, Folcroft PA19032.

Sulzer’sProven ProcessSolutions for theBiofuel Industry

Sulzer Chemtech Ltd

Process TechnologyGewerbestrasse 284123 Allschwil 2SwitzerlandPhone +41 61 486 37 37Fax +41 61 486 37 [email protected]

Sulzer Chemtech is market leaderwhen it comes to distillation in bio -ethanol and biodiesel plants.

For advanced biofuels production, SulzerChemtech has delivered liquid-liquid extraction, distillation, and membrane separation units globally. Non-food bio-mass has a huge potential as future basisfor biofuels and biochemicals. SulzerChemtech offers proven process solu-

tions that fit customers’ advanced biofueland biorefinery developments. Our solu-tions are based on a wide range of thermal separation technologies, also inoptimized, hybrid combinations. We areexperienced in developing and testingprocess concepts and turning them intocommercial plants. We are a reliable inno-vation partner and preferred supplier forour customers globally. We deliver our solutions with a guaranteed performance.

Mytsac Technical Review

Documents

Transcript of Mytsac Technical Review