IntroducIng VErdEr ScIEntIFIc dIVISIon · 2017-06-21 · For many years Retsch and Retsch...

For many years Retsch and Retsch Technology have been the core of Verder’s Scientific Division which covers the business segment “laboratory equipment” within the Verder group. Eltra and Carbolite are among the companies which have recently become part of this division and will be introduced in this issue.

Laboratory Mills and Sieve Shakers

Optical Particle Analyzers

High-Temperature Furnaces and Ovens

Combustion Analyzers and Thermogravimetric Analyzers

IntroducIng VErdEr ScIEntIFIc dIVISIon

Issue 38 | Information from the field of solids preparation and characterization in laboratories and processing industries

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The German-Dutch technology group Verder with more than 800 employ-ees world-wide is composed of the core business areas Scientific Division (laboratory equipment) and Liquids Division (positive displacement pumps). Retsch, the world’s leading manufacturer of sample preparation equip-ment and Retsch Technology, a leading solution provider for optical par-ticle characterization, have been part of Verder’s laboratory sector for many years. Recently the companies Eltra and Carbolite, amongst others, have been incorporated into Verder’s Scientific Division, providing a per-fect complementation to the laboratory and analytical product portfolio.

thE nEw VErdEr ScIEntIFIc dIVISIon

Dear Readers, Customers and Business Partners,

Maybe you have noticed when looking at the cover of this “sample“ that we will not only present products and applica-tions from the fields of milling and particle analysis in this issue. The Scientific Division of the Verder Group (www.verder-scientific.com), to which Retsch and Retsch Technology belong, has incorporated two addition-al companies in 2012: Eltra GmbH, a specialist for combus-tion analyzers; Carbolite Ltd., a leading manufacturer of high temperature laboratory and industrial furnaces. Both com-panies will be introduced in more detail on the following pages.

Still, there are plenty of news about size reduction and par-ticle analysis in this issue as well. With the jaw crusher BB 50 and the new generation of the CryoMill we introduce two novelties based on well-proven instruments. Two arti-cles on particle analysis present the line of RETSCH sieving machines and describe the benefits of characterizing con-struction materials with the CAMSIZER XT.

We hope you enjoy reading this issue of „the sample”!

Yours

Dr. Juergen PankratzDirectorVerder Scientific Division

EDITORIAL

Nanotechnology is one of the most innovative technologies of our time. The use of nanoparticles allows for groundbreaking changes in many different areas.

Reducing the particle size of a material down to the submicron range often results in the generation of new properties which open up new possibilities of application. Mac-roscopic pieces of the same material do not necessarily share the properties of nanoparticles, such as, for example, stronger hardness, breaking resistance and toughness at low temperatures as well as superplasticity at high temperatures, the formation of additional electronic states, high chemical selectivity of surface structures and substantially increased surface energy. Therefore nanotechnology is of particular interest to material researchers.

One way to create nano particles is with the “top down” method which involves reduc-ing larger particles to nano scale sizes by grinding. RETSCH is currently develop-ing the revolutionary Nano Ball Mill Emax which produces nano particles more quickly and easily than ever before!

The innovative grinding mechanism of the Nano Ball Mill Emax combines the benefits of different mill types: high-frequency impact (mixer mill), friction (vibratory disc mill) and powerful, circular grinding jar movements (planetary ball mill) allow for unprec-edented grinding performance.

Market launch: 4th quarter 2013

thE nano rEVolutIon New Nano Ball Mill Emax

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thE nEw VErdEr ScIEntIFIc dIVISIon

www.retsch.com | the sample 38 |

thE nano rEVolutIon New Nano Ball Mill Emax

RETSCH GmbH: Laboratory grinders and analytical sieve shakers for neu-tral-to-analysis sample preparation and characterization of solids in the context of quality control. www.retsch.com

Retsch Technology GmbH: Optical analyzers for particle characterization of powders and suspensions in the context of quality control. The instru-ments cover a size range from 0.3 nm to 30 mm.www.retsch-technology.com

ELTRA GmbH: Combustion analyzers for the determination of carbon, sul-fur, oxygen, nitrogen and hydrogen in solids. Thermogravimetric analyzers for the determination of parameters such as moisture, ash, volatile compo-nents etc. www.eltra.org

Carbolite Ltd.: High-temperature furnaces and ovens used in laboratories (ashing and heat treatment models) as well as for industrial applications (e.g. precious metals or ceramics). www.carbolite.com

Video at:www.retsch.com/emax

BENEFITS:

n Speeds of 2000 min-1 and more allow for ultra-fast pulverization of the sample

n Two grinding stations for grind-ing jars up to 125 ml

n Suitable for dry and wet grinding

n Absolutely safe and intuitive operation

Design Study

| the sample 38 | www.retsch.com4

Since March 2012, ELTRA GmbH is part of Verder’s Scientific Division. The company, which was founded in 1981, is a world leader in the development and production of elemental analyzers. Starting with combustion analyz-

ers for carbon and sulfur determination, ELTRA has extended its product range over the years with analyzers for oxygen, nitrogen and hydrogen. The company has been continually increasing its world market share with high-quality instru-ments at affordable prices; the current export share is almost 90%. Customers come from industries such as steel, automotive, aviation and mining. At the new headquarters in Haan, under the same roof as RETSCH, ELTRA employs 35 highly qualified people who are in charge of development, final assembly and commissioning of the analyzers.

Combustion analyzers for C, S, O, N, HElemental analyzers for carbon, sulfur, hydrogen, nitrogen and oxygen are ELTRA’s core products. These systems quickly and precisely determine the con-tent of non-metallic elements in laboratory samples. There are various reasons for analyzing C, S, O, N and H: The carbon content in a coke sample is analyzed, for example, to determine the calorific value; sulfur, however, is an unwanted element as it is converted into sulfur dioxide by combustion. Steel is analyzed for its carbon, nitrogen, sulfur, oxygen and hydrogen content as these elements have an influence on the physical properties of the material.

To analyze the carbon content, the sample is heated to 1,000 °C in an oxygen stream. The carbon dioxide produced in this process is then detected in an infra-red cell. Simultaneously, sulfur oxidizes to SO2 and the content is also determined in infrared light, but with another wave length.

ElEMEntal analYSIS

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nEw in the Verder Scientific DivisionMORE INFORMATION ATwww.eltra.org

The ONH-2000 is designed for the rapid determination of oxygen, nitrogen and hydrogen

www.retsch.com | the sample 38 | 55

The CS-2000 analyzes both organic and inorganic samples

ELTRA analyzers offer a great variety of measuring ranges; for carbon, for example, from a few ppm in steel to 100% in activated charcoal. One of the benefits of combustion analysis over other methods is the short analysis time which is typically 1 minute.

Organic samples (coal) and inorganic samples (steel) are combusted in a differ-ent way. For the analysis of steel an induction furnace is used which quickly heats the sample to a temperature of 2,000 °C; inorganic samples, in contrast, are heated in a resistance furnace to 1,350 °C.

Therefore, ELTRA analyzers have a modular design: there are different instru-ments for the analysis of organic and inorganic samples and one instrument which combines both possibilities. The ELTRA CS-2000 is the only analyzer in the market which is equipped with both an induction and a resistance furnace. This is a big advantage for users which need to analyze both sample types. ELTRA analyz-ers simultaneously determine sulfur and carbon in up to 4 measurement ranges.

The number of infrared cells and their sen-sitivity can be individually selected accord-ing to the user’s requirements. It is also possible to determine total inorganic carbon (TIC) by using a special module; sulfur can be determined by fractional analysis.

The ELTRA product range is completed by analyzers for hydrogen, nitrogen and oxygen as well as thermogravimetric analyzers. Solutions for automated high throughput applications are also provided by ELTRA.


The UK-based company Carbolite is one of the leading manufacturers of electrically heated laboratory fur-naces and ovens. Carbolite products are exported

worldwide for use in industries such as aerospace, ceramics, metals, mining, pharmaceuticals, electronics, composites and materials science. Carbolite has subsidiaries in Germany, France and the US and relies on a global distribution network.

In addition to routine ashing and heat treatment models, Carbolite also produces more specialized furnaces and ovens. Among the huge variety of applications are coal, coke and iron ore testing, gold assay and melting, ash fusion testing, anal-ysis of organically bound tritium in radioactive waste and clean room use to name but a few.

Carbolite’s capacity for innovation is reflected in the develop-ment of instruments which are unique in the market. The microwave assist CMAT furnace utilizes a combination of radiant heating and microwave energy. It heats samples up to 1600°C, simultaneously from outside and from inside the sample. Another unique design is the moving wall coke test oven used to determine the swelling of coking coal during processing in plants worldwide.

Carbolite has a reputation for flexibility and the capability to offer tailor-made solutions for customers’ individual requirements based on high quality engineering and cus-tomized designs. The extensive product range includes cham-ber and tube furnaces operating up to 1,800°C and ovens operating to 700°C in sizes from 1 liter standard products to 10,000 liter bespoke pilot and production plant.

lEadIng hEat tEchnologY

MORE INFORMATION ATwww.carbolite.comnEw in the Verder Scientific Division


lEadIng hEat tEchnologY

One of the most frequent applications for laboratory furnaces involves heating samples so as to remove all organic content and produce an ash residue. Perhaps it is because the process is central to so many investigations, in so many laboratories, that in spite of its commonplace nature there are wide varia-tions in the specific requirements of ashing furnace users. To accommodate these variations Carbolite have developed with-in the standard product range eight different furnaces across five model types. These provide different chamber sizes and rack systems in order to handle a range of sample numbers and sizes, as well as different maximum temperature and chamber designs in order to manage some of the challenges produced by the test materials.

The AAF series are purpose-made 1,100°C ashing fur-naces, designed so that the chambers have high levels of pre heated airflow. This ensures that complete combustion of the sample takes place, without the high airflow cooling or impair-ing uniformity within the furnace chamber. In particular AAF 11/3 and AAF 11/7 are designed to meet the specific require-ments defined with the ISO 1171:2010 and ASTM D3174-04(2010) Standard Test Methods. In the AAF series and the AAF 12/18 the heating elements are fully shielded from the potentially damaging accumulation of carbon contamination. The three sizes of AAF 11 are able to accommodate a variety of workloads.

Some sample materials generate corrosive or acidic vapors as they combust and it is for these applications that the GSM 11/8 was designed. The vitreous chamber lining provides superior containment of aggressive vapors and has a much higher resis-tance to chemical attack than the insulation materials used in conventional furnaces. It also provides protection to the heat-ing elements.

Finally there are applications where the fumes from the ashing process must be completely combusted, either to meet envi-ronmental constraints or simply because the test materials generate large amounts of smoke. For situations like these the ABF 8/28 is equipped with an independently controlled high temperature afterburner that treats the fumes from the primary ashing chamber, so that the final exhaust from the furnace is much cleaner.

Like all of the furnaces in the Carbolite range there is a choice of ‘standard’ options available at the time of ordering, e. g. programmable controllers. If this breadth of options does not meet a customer’s specific needs, the fact that each furnace is manufactured to order in Carbolite’s factory, using Carbolite’s designs, enables the provision of bespoke modifications to pro-vide the optimum possible solution to the customer’s require-ments.

Bespoke ashing furnaces for any material

Ashing furnaces of the AAF series

Tube furnace GHA with max. temperature of 1,200 °C

All instruments are manufactured at Carbolite’s UK headquarters


Jaw cruShEr BB 50The new bench top model

BENEFITS

The proven features of the bench top crusher for size reduction of smaller sample volumes have been perfect-ed further with the new model BB 50:

n Large fold-back hopper

n Removable crusher arm for easy cleaning

n Adjustable speed allows adaptation to sample char-acteristics

n Convenient operating key-pad with digital display

n Memory for gap width setting

For coarse and primary size reduction of medium-hard, hard, brittle and hard-tough sample materials jaw crushers are the products of choice. RETSCH offers a complete series, from bench top unit to floor models in

various sizes. The proven concept of the bench top model for processing small-er sample volumes in the lab has been further optimized with the new BB 50. The dust-tight instrument reduces samples with a feed size of up to 40 m in one single operationn to a final fineness of up to 0.5 mm. RETSCH’s bench top BB 50 is unique and its high crushing performance unpar-alleled by any other jaw crusher in the market!

Market launch:2nd quarter 2013

MORE INFORMATION ATwww.retsch.com/bb50


Superiority in detailThe BB 50 is designed for a very efficient and convenient size reduc-tion process. The variable speed can be set between 550 and 950 min-1 to adapt the crushing process to sample requirements. Another advantage of the BB 50 is the so-called zero point adjust-ment. Sooner or later, the breaking jaws will show signs of wear which will affect the reproducibility of the size reduction process. This effect can be compensated by adjusting the zero point. A sign in the display indicates if the jaws need to be replaced altogether. The possibility to reverse the rotating direction is helpful if too much sample material has been fed to the crusher causing it to block. The simple push of a button restarts the process.

Easy operation and cleaningWorking with the new jaw crusher is easy and safe. The large, clear-ly structured operating panel allows for digital display of param-eters such as gap width and speed. The sample material is con-veniently fed to the crusher via the large hopper equipped with splash-back protection.

For easy cleaning the fold-back hopper and crusher arm can be removed without using tools. The user can also exchange the break-ing jaws if the crusher needs to be converted for different applications.

Neutral-to-analysis preparationThe BB 50 can be operated with breaking jaws and wearing plates made of 5 different materials. The suitability of a particular mate-rial is determined by the sample material and the subsequent analy-sis. The BB 50 is also available in a version for heavy-metal-free grinding.

If a variety of sample materials is processed on a regular basis, the optional lid for the collecting receptacle ensures that the fine resi-dues from previous applications fall on the lid and not into the recep-tacle. Thus it is possible to avoid cross contaminations.

Easy removal of crusher arm

Large digital display

The collecting receptacle accommodates 2 liters

Setting the gap width

*depending on feed material and instrument configuration/settings

PERFORMANCE DATA

JAw CRuSHER BB 50

Applications: coarse and pre-crushing

Feed material: medium-hard, hard,

brittle, hard-tough

Feed size*: < 40 mm

Final fineness*: < 0.5 mm

Market launch:2nd quarter 2013

Some sample materials have properties which make size reduc-tion at ambient temperature impossible. If, for example, very elastic materials need to be ground or volatile components

have to be preserved for further analysis, it is essential to carry out cryogenic grinding. The use of liquid nitrogen helps to embrit-tle the sample, thus improving its breaking properties, and preserv-ing volatile substances which otherwise would escape due to the frictional heat produced by the grinding process.

RETSCH has developed the CryoMill especially for this application. An integrated cooling system ensures that the grinding jar is continually cooled with liquid nitrogen before and during the grind-ing process. Thus the sample is embrittled and volatile components are preserved. Thanks to the Autofill System, liquid nitrogen is continually refilled in the exact amount which is required to keep the temperature at –196 °C.

Grinding in the CryoMill is effected by impact and friction. The grinding ball moves freely inside the grinding jar which allows for thorough pulverization of the sample, in contrast to other cryo-genic mills with differently shaped grinding tools.

Based on an extensive dialogue with users of the CryoMill, RETSCH was able to integrate a variety of suggestions into the further development and optimization of the new product generation. As a result, the new CryoMill makes grinding with liquid nitrogen as convenient and effective as never before.


BENEFITS

Cryogenic grinding was never more convenient or efficient

n Increased oscillating fre-quency of up to 30 Hz allows for 50% higher grinding energy

n Reinforced housing and opti-mized liquid nitrogen duct

n Clearly structured user interface, memory for 9 SOPs

n Additional accessories such as adapter for 6 reaction vials

crYoMIll The New Generation

MORE INFORMATION ATwww.retsch.com/cryomill

Improved grinding results thanks to increased vibrational frequencyThe maximum vibrational frequency of the new CryoMill gen-eration is 30 Hz. This allows for a considerably higher grinding energy which results in smaller grind sizes. This is particu-larly true for extremely tough and elastic materials.

ExAMPLE PLASTIC (PE-LD)

LD polyethylene is a highly elastic material which is very difficult to grind with impact and friction, even at very low temperatures. Compared to a grinding process at 25 Hz, the results at 30 Hz have improved by 50%.

Parameters: 6 g PE-LD granulate in grinding jar 50 ml, stainless steel,1 grinding ball Ø 25 mm, stainless steel,5 cycles of 2 min each, with 1 min intermediate cooling at 25 Hz (red curve) and 30 Hz (blue curve)

ExAMPLE LEATHER

Leather is a very tough and fibrous material. These prop-erties make it very robust for usage but also fairly difficult to grind. Processed at 25 Hz for a short interval, the mate-rial is only slightly torn up whereas at 30 Hz, after the same grinding time, it is completely pulverized.

Parameters: 8 g leather (approx. 8x8 mm) in grinding jar 50 ml, stainless steel, 1 grinding ball Ø 25 mm, stainless steel, 3 cycles of 2 min each, with 1 min intermediate cooling at 25 Hz (left) and 30 Hz (right)

Q3 [%]

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Convenient operationThanks to the improved liquid nitrogen duct and electronic monitoring, direct contact of the user with LN2 is virtually impossible. The new CryoMill offers a maximum of oper-ational safety while ensuring low LN2 consumption.

The operating interface has become more user-friendly; the clear structure allows for intuitive programming of grinding cycles.

The new product generation features memory for 9 Stan-dard Operating Procedures (SOPs), allowing to carry out routine applications at the push of a button.

Inserting and releasing the grinding jar has become even easier and safer.

New accessoriesThe adapter for reaction vials now accepts up to 6 tubes instead of only 4.

The 10 ml grinding jar closes the gap between the 5 ml and the 25 ml jar.

For tough and elastic materials as well as for samples

which contain volatile components, cryogenic grinding is

the only method to obtain the required analytical fineness.

The Retsch CryoMill has proven to be the perfect tool for

grinding temperature-sensitive materials which cannot be

processed at room temperature. The grind sizes are sig-

nificantly finer than those produced by comparative mills

and have further improved with the new product genera-

tion. Especially for difficult materials such as polyethylene

or leather the Retsch CryoMill is the ideal instrument for

sample preparation.

Summary

PERFORMANCE DATA

CRyOMILL

Applications: size reduction, mixing, homogenization,

cell disruption

Feed material: hard, medium-hard, soft, brittle,

elastic, fibrous

Feed size*: ≤ 8 mm

Final fineness*: ~ 5 µm

Batch size/feed quantity*: max. 20 ml

*depending on feed material and instrument configuration/ settings

THE RETSCH RANGE OF SIEVING EqUIPMENT INCLUDES:

n Vibratory Sieve Shakers

n Horizontal Sieve Shakers

n Tap Sieve Shakers

n Air Jet Sieving Machines

n Test Sieves

n Evaluation Software


SIEVIng MachInESFrom coarse bulk goods to finest powders

For the characterization of bulk goods of different forms and sizes, the knowledge of their particle size is essential. The particle size distribution, i.e. the number of particles of different sizes, is

responsible for important physical and chemical properties like solubil-ity, flowability and surface reaction. In many industries such as food, pharmaceutics and chemistry traditional sieve analysis is the standard for production and quality control of powders and granules. It is used to divide the material into size fractions which are then weighed. Advantages of sieve analysis include easy handling, low investment costs, precise and reproducible results in a comparably short time and the possibility to separate and work with the particle size fractions. Therefore, this method is a widely accepted alternative to analysis methods using laser light or image processing.

RETSCH’s line of sieve shakers is the most comprehensive offering with regards to sieving motions, measuring ranges and sieve diameters, thus covering virtually any bulk material – from agglomerating powders to solid rocks.

20 µm 25 mm

20 µm 25 mm

10 µm 4 mm

20 µm 40 mm

Sieve analysis

AS 200

AS 300

AS 450

AS 400

AS 200 tap

AS 200 jet

n dry measurementn wet measurement

THE PERFECT SOLUTION FOR EACH MEASURING RANGE

45 µm 63 mm

25 µm 125 mm

1 µm 1 mm 1 m

MORE INFORMATION ATwww.retsch.com/as200jetwww.retsch.com/as450

The AS 450 control is RETSCH’s first sieve shaker for 400 mm and 450 mm sieves which operates with a three-dimensional sieving motion. The controlled elec-tromagnetic drive offers optimum adaption to every product. Sharp fractions in a size range from 25 µm to 125 mm are obtained even after very short sieving times.

The AS 450 is suitable for dry and wet sieving. RETSCH‘s innovative Continuous Energy Transformation Technol-ogy (CET) allows for amplitudes up to 2.2 mm even with maximum loads of 25 kg. This makes the AS 450 supe-rior to all other known sieve shakers based on conven-tional electromagnetic or imbalance drives. The AS 450 is also available in a “basic” version for dry sieving of up to 15 kg.

AS 450 control – 3-D sieving of heavy loads

The Air Jet Sieving Machine AS 200 jet is particularly suitable for sieve cuts of powdered materials which require efficient dispersion and desagglomeration. It covers a size range from 10 µm to 4 mm. The sieving method is very gentle on the material, and the average sieving process only takes 2-3 minutes. A special feature of the AS 200 jet is the Open Mesh Function which helps to greatly reduce the number of near-mesh par-ticles. This provides optimum separation efficiency and also excellent reproducibility. The option to store up to 9 SOPs and to use the quick Start Mode for sieving under standard conditions makes the AS 200 jet very user-friendly. Accessories include an automatic vacuum regulator and a cyclone.

AS 200 jet – Air jet sieving of fine powders

13 www.retsch.com | the sample 38 |

EasySieve®, the software for particle size analyses, ex-ceeds manual evaluation in many aspects. The software guides the user through the necessary measurement and weighing procedures – from the registration of the weight of the sieve to the evaluation of the data, monitoring each step for plausibility. The abundance of evaluation options allows for absolute flexibility with regards to individual re-quirements.

Evaluation Software EasySieve®


caMSIzEr XtQuality control of building materials

Retsch Technology’s CAMSIZER xT reliably analyzes both particle size and particle shape of fine powders with Dynamic Image Analysis. It is based on the well-proven optical particle analyzer CAMSIZER but is optimized for

finer samples from 1 µm to 3 mm. Both improved optical resolution and new options for material dispersion allow for an extended application range. A selec-tion of dispersion modules allows for desagglomeration of the sample without breaking individual particles. This flexible “x-Change” system consists of three dispersion modules:

1. x-Fall: Dispersion by gravity (free fall mode)2. x-Jet: Dispersion by air pressure with adjustable pressure and variable nozzle geometry3. x-Flow: Dispersion in liquids, optionally by ultrasound

The typical measurement time varies between 1 to 3 min depending on the desired measuring statistics. Reported result parameters include smallest diameter, length, mean diameter, aspect ratio, symmetry, sphericity, and convexity. CAMSIZER xT results can easily and accurately match historic results from other techniques (sieving, microscopy, light diffraction) with the appropriate selection of result parameters and automated software features.

The CAMSIZER xT has been successfully installed at building material plants around the world replacing sieve analysis by providing quick, reliable high reso-lution results while still matching historic sieve data. .

BENEFITS

n High resolution: more than 3,000 size classes in one measurement

n Faster and more reliable measurements (1 – 3 min-utes)

n Reproducible results, inde-pendent from operator

n Wide dynamic range from 1 µm to 3 mm

n Reliable detection of over-sized and undersized parti-cles (< 0.1 %)

n Flexible, controlled sample dispersion of both powders and suspensions

n Particle shape analysis

MORE INFORMATION ATwww.retsch.com/camsizerxt


APPLICATION ExAMPLE

Most sand used in building materials is analyzed for particle size

distribution by sieving. The CAMSIZER xT can replace the older

sieve technique with a quicker, easier to use instrument that pro-

vides higher resolution particle size results as well as particle

shape information. Figure 1 (top) shows two types of sand from

different locations, measured with the CAMSIZER xT. This sand

is used as a layer in glass-reinforced plastic pipes to increase the

stiffness. The red curve is slightly bimodal. Sand with a wide size

distribution can be more closely packed in the core of the pipe

which gives the finished product a higher stability. The lower graph

shows a sand sample which was measured by sieving (blue) and

by the CAMSIZER xT (red). The results compare extremely well,

proving that CAMSIZER xT easily matches historic sieve results.

How particle size and particle shape influence product quality

Fig. 1: CAMSIZER XT results for sand. The upper graph dis-plays the frequency distribution q3(x). The lower graph shows the size results obtained by sieving and CAMSIZER XT.

PERFORMANCE DATA

CAMSIZER XT

Measuring range: 1 µm to 3 mm

10 μm to 3 mm (gravity dispersion)

1 μm to 1.5 mm (air pressure dispersion)

1 μm to 600 μm (wet dispersion)

Type of analysis: dry and wet analysis

Sample volume: < 100 mg – 100 g

(depending on sample and measurement mode)

The particle size distribution has various effects on the processing of building materials such as:

n Powder flow: a wide distribution or too many fines reduce flowability

n Segregation: a wide distribution leads to size segregation, e. g. during transport

n Rheology: fines or irregularly shaped particles increase viscosity

The effects of oversized particles, i. e. particles which are bigger than the desired size range, include:

n Poor quality of the final product (grains sticking out of the plaster, rough sur-faces of tiles, inhomogeneous materials break more easily)

n Changes in the “look and feel” of the end products

n Changes in the process parameters of the end product, e. g. flow behavior

n Blockage of filters or sieves in production

n Removal of oversized particles from the production process and recycling (addi-tional costs and effort)

Sand for glass-reinforced plastic pipes

The building materials industry uses naturally occurring substances such as rock, clay, sand and wood as well as synthetic polymers and multiple combinations of both (composites). No matter which type of building material, the particle size and shape of the raw materials influence the quality and performance of the end product, and therefore need to be analyzed as part of the quality control process.

Oversized particles can also indicate problems in the production process such as holes in or contamination of a produc-tion sieve, inadequate settings or wear in a crusher or mill, which is used for size reduction.

Undersized particles create a similar set of problems and can, moreover, lead to pollution of the workplace and filter block-age by dust.

The particle shape information also plays an important role in the quality control of building materials. It provides insight into changes that can affect end product performance. In addition to effects on rheology and compaction, irregularly shaped particles have a larger surface area and are therefore more difficult to coat - requiring more adhesive or binder..

q3 [%/mm]

Particle size0 0,2 0,4 0,6 0,8 1,0 1,2 1,4 1,6

sample 1sample 2

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CAMSIZER xTSieve analysis

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Retsch GmbH Retsch-Allee 1-542781 Haan, Germany

Phone +49(0)2104/2333-100Fax +49(0)2104/2333-199

E-Mail [email protected] www.retsch.com

Retsch Technology GmbH Retsch-Allee 1-542781 Haan, Germany

Phone +49(0)2104/2333-300Fax +49(0)2104/2333-399

E-Mail [email protected] www.retsch-technology.com

Eltra GmbH Retsch-Allee 1-542781 Haan, Germany

Phone +49(0)2104/2333-400Fax +49(0)2104/2333-499

E-Mail [email protected] www.eltra.org

Carbolite Ltd. Parsons Lane, Hope, Hope Valley, S33 6RB, UK

Phone +44(0)1433 / 620011Fax +44(0)1433 / 621198

E-Mail [email protected] www.carbolite.com

Defy gravity!The first prize is an extraordinary adventure

worth € 8,000.

www.retsch.com/win

Contact:

Please refer to the respective website for your local contact.

C O M P E T I T I O NWin total prizes worth

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IntroducIng VErdEr ScIEntIFIc dIVISIon · 2017-06-21 · For many years Retsch and Retsch...

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