Feasibility study: Wood gasification power plant in Belarus (2012)

Assessment of Wood Chips Gasification in Belarus

Dr. Petr V. Dudin 10/09/2012 (Leiden - Minsk)

Dr. Petr Dudin | 2012

The BDC R&D company is involved in development and engineering design of pilot and industrial gasifiers.

BDC R&D also has a range of gas purification and catalyst technologies that can to tackle tars issues.

We are open to discuss emerging opportunities in gasification and gas cleaning technologies with laboratories, funds and entrepreneurs.

Disclaimer: Please, bear in mind that the information presented hereby might be outdated. The conclusions and financial estimations are also a subject of chosen process efficiencies, estimations and economic modeling, which is based on several assumptions.

Please, contact Dr. Petr Dudin via email ( [email protected] and [email protected] ) for further details.

Figure 1: Energy potential from biomass feedstocks Mtoe/a

0,0

0,5

1,0

1,5

2,0

2,5

Fore

stry

Agr

icul

ture

Was

te

Bio

ener

gycr

ops

Mtoe

Sewage gas

Landfill gas

Municipal waste

Livestock biogas

Agricrops

Forest industry residues

Forest residues

Firewood

Data source: IIASA, ÖBF, Pöyry

• Wood is the main source of bio-energy, which comes from harvestings (85% of the total energy wood*):

• 7.8 million m³ per year are energy round wood (stem wood)• 1.5 million m³ of wood chips and offcuts • 0.5 million m³ are harvesting residues

• Energy and Short Rotation Crops have a potential of ca. 1.0 Mtoe/year* Strategy of Energy Potential Development and the State Programme of Forestry Development for 2011-2015

1. Biomass Energy in Belarus


• Forests are state property and 86% of it is managed by Ministry of Forestry

• There are 95 district forestry entities (leskhoz) in Belarus, that manage the forests

Woodchips production

• 27 leskhozs are producing over 400, 000 m3 of wood chips (2008 data).

• Wood chips are currently exported at price €25 per metric ton (in 2012)

• The pellets production was estimated at 57,000 tons a year at 29 enterprises

1.1. Forestry


• Ministry of Forestry suggests to purchase wood chips in Gomel region, where

there is over 250,000 m3 is produced annually, while only 140,000 m3 is used in

the area.

• According to Business Assembly Gomel region is the best region for “doing

business” in 2012.

Leskhoz name Annual producing capacity (m3)

Gomel region Forestry unit 250 000

Gomel 20 000

Elsk 22 000

Kalinkovichi 20 000

Komarin 6 000

Mozyr 22 000

Oktyabskiy 20 000

Petrikov 60 000

Rechitsa 80 000

1.2. Wood chips availability in region


• approximately 100,000 ha of land are currently available for ‘energy’ planting• 0.3 Mha may be developed for ligno-cellulosic energy crop production, such as short

rotation willow or energy grasses (miscanthus), in the short term; this represents 9% of current pasture area

• As of 2011, national forestry enterprises have created 1,176.2 ha of plantations for short rotation woody coppice (SRWC) species, mainly for fuel energy goals.

• The volume of fuel wood per ha of developing plantations with ages of 20-25 years is 200 m3 (50-55 toe).The mass of fuel wood per ha of willow cropped in 3 years is 18-22 tons (ca. 50% moisture content)

• In accordance with the State Programme of Forestry Development for 2011-2015, the creation of more than 1.000 ha of plantations of SRWC species for fuel energy goals is envisioned by forestry enterprises of the Ministry of Forestry.

• Fast growing plantations of poplar or willow species (optimal age - 3 years )

• Modern harvesting and chipping system (Jaguar mega); a tractor and 2 trailers to feed 5 MW forest chips CHP plant

• Pöyry 2012 report estimates SRWC to cost 29 €/t at road-side, 31 €/t at gate, 42 €/MWh for CHP production

1.3. Energy Crops and Short Rotation Crops


• Pöyry (2012 report) estimates forest chips production costs in Belarus at 16 €/m³

(road-side); 22 €/m³ (at a gate); CHP electricity cost for production 40 €/MWh.

Цена щепы без НДС из отходов лесозаготовок 24,3 €/пл. куб. мСырье и

материалы; 0,00 €Единый платеж; 0,94 €

Накладные расходы; 2,63 €

Прибыль; 3,05 €

Заработная плата основных рабочих с начислениями;

1,18 €

Затраты на содержание и эксплуатацию оборудования;

16,51 €

Цена щепы без НДС из отходов лесозаготовок 19 €/пл. куб. мСырье и

материалы; 0,00 € Заработная плата основных рабочих с начислениями;

2,21 €

Единый платеж; 0,73 €

Прибыль; 2,38 €

Накладные расходы; 2,56 € Затраты на

содержание и эксплуатацию оборудования;

11,10 €

1.4. Wood chips economicsc

Costs of the chips produced form fallen wood / dead wood would be higher due to additional transportation and handling costs.

Although wood chips are available in Belarus at a relatively low price, the chips fuel cost can be reduced further by building own supply chain.Own wood chips supply chain will benefit from:

(i) low labour cost, (ii) low fuel prices, (iii) low (round)-wood prices at a cutting forest site

Economical evaluations presented on these graphs is based on 14% profitability margin


Terrain chipping method

Chipping on road side method Chipping at power plant method

• Ledtitsky’s (2012, BSTU report) estimates the production price for wood chips 19 €/m³ (road side) and 24.5 €/m³ (terrain chipping). 50 km transport leg is considered.

• Residues from the wood-cutting area are not widely utilized in Belarus. Therefore, can be considered as a (possible) cheaper source of wood chips.

• MAZ (Minsk Automobile Plant), MTZ (Minsk Tractor Plant) and Amcador currently produce a range of mobile chippers, forwarders and wood chip trucks (80 m3 and 40 m3 capacity) which are available at relatively low price.

24.5 €/m³

19 €/m³

1.5. Considering Wood chip production


1.6.


-30 -20 -10 0 10 20 30

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m3

woo

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$

roundwood cost, VARIATION /%

$30 per m3 ofround-wood

It is expected the cost of wood chips to be significantly reduced if own supply chain is built. The wood will be cut and logged at a forest site. A tractor will load logs to a truck, which will carry the wood logs to the plant. Wood will be chipped at the plant.Considering round-wood and/or wood can be purchased at a price $ 30 per cubic meter wood,the wood chips price would be 14 $/m3. Compared to 19.2 $/m³ (road-side); 26.4 €/m³ (at a gate);

1.7. Own wood chips supply chain

harvester truck chipper

This requires 2 trucks (~ $ 75,000 each), 1 harvester ($400,000), 1 chipper ($100,000), 2 tractors for logs loading (40,000 each)Assumption in calculations. Distance between the plant and the forest site will be 50 km; amortization time for the machinery – 8 years; 8 working hours per day and 280 working days in a year is considered. Wood density: 0.8 t/m3, wood moisture: 50%, chipper productivity: 10 tons/hour

2. Gasification technology

• Gasification is a technology, where a carbon-containing fuel (e.g. coal, wood, oil, etc.)

is converted in a gasifier to a produced gas, which has a significant heat value.

• The main components of a gas, produced in a gasifier is CO, CO2, H2 and N2 (comes from air) • Relatively low operation temperature of a gasifier (ca. 750-850 ˚C) ensures low NOx content in a produced gas.• Produced gas can be upgraded (purified) and used for methanol, ethanol or alkenes synthesis or, alternatively, burned in a CHP/turbine unit.

• Gasification chemistry is generally driven by two reactions:

steam producing monoxide

water gas shift reaction A schematic of a downdraft gasifier


2.1.1. Simple gasifier design

Updraft gasifier(eg. British Gas Lurgi)

Downdraft gasifier(eg. Ventec)

Crossdraft gasifier

Gasifiers can be classified according to:– oxidation agent: air, oxygen or/and steam– heating: direct (autothermal) or indirect (allothermal)– pressure at gasification: atmospheric or pressurized– reactor type: fixed bed, fluidized bed, entrained flow, twin-bed

H.A.M. Knoef, HANDBOOK ON BIOMASS GASIFICATION, 2005Dr. Petr Dudin | 2012

2.1.2. Simple gasifier design energy parameters

Fixed-bed gasifiers are of simple design and operation, making them suitable for small-scale applications in the range of a few hundred kWth. Fixed-bed gasifiers can be operated in either batch or continuous mode.


Bubbling Fluidized bed (BFB) Gasifier

• Fluidized bed gasifiers have the reactors where solid particulate material is suspended in moving liquid or gaseous fluid. Some can contain Ni particles to promote decomposition of hydrocarbons to CO and H2.

• CFB gasifiers can handle high-ash-content fuels. They are well suited for continuous operation and scalable to a wide range of sizes, allowing for large-scale industrial plants.

• CFB gasifiers are also somewhat cheaper to construct than are BFB gasifiers of corresponding capacity. The Värnamo gasifier, 18 MWth, is an example of a pressurized, airblown, CFB.

FB Advantages. Feedstock flexibility resulting from easy control of temperature, which can be kept below the melting or fusion point of the ash (rice husks), and their ability to deal with fluffy and fine grained materials (sawdust etc.) without the need of pre-processing.

FB may have some Problems with feeding, instability of the bed and fly-ash sintering in the gas channels can occur with some biomass fuels. Biomass loading can’t be lower 70%

(CFB)

2.2. Advanced gasifier design (fluidised bed)


2.2.1. MILENA gasification process (fluidized bed)

• In the MILENA gasification process (Dahlman and ECN, Netherlands) the produced gas is suitable for application in a gas engine or gas turbine because of the higher calorific value of the gas (typical 16 MJ/mn

3 dry, compared to 4 – 7 MJ/mn3 for a conventional air blown gasifier) and the complete

conversion of the fuel (typical fuel conversion for downdraft or fluidized bed gasifiers is 85 - 95%).

• The MILENA lab-scale installation was taken into operation in 2004. A pilot plant was constructed in 2008. The accumulated gasification hours of the MILENA plants is now over 3000 hours. MILENA gasification and OLGA (gas cleaning technology) so have been employed in combination for biomass-gasification (mainly wood).

• Use of a settling chamber in the MILENA process instead of a cyclone to separate the char and bed material from the producer gas.

http://www.milenatechnology.com/

• The gasifier contains separate sections for gasification and combustion.

• The main difference between the MILENA process and the FICFB (Güssing) process is the gasification in a riser reactor instead of Bubbling Fluidized Bed (BFB). The advantage of using a riser is that the area that needs to be fluidized is smaller; therefore the amount of fluidized gas (steam) is smaller.

• as the ECN claims, MILENA gasifier technology gas overall efficiency ~83% and aims to work at large scale plants (>30 MW-h energy input)


http://www.milenatechnology.com/

2.2.2. FICFB (Güssing) process

http://www.ficfb.at/

• A gasifier comprised of fluidized bed gasification reactor that produces a gas with a HVV up to 15 MJ/Nm³ (>13 MJ/m3) and nearly free of nitrogen.

• The gasification process is based on an internally circulating fluidized bed system and consists of a gasification zone fluidized with steam and a combustion zone fluidized with air. The circulating bed material acts as heat carrier from the combustion to the gasification zone. Gas mixing between these two zones is avoided by construction measures.

• The gasifier is characterized by a very compact design.

• 5 electricity producing plants, 1 methanol-producing and 1 hydrogen-producing plant were in operation in 2011

• Low tar content due to steam gasification• Gas quality is independent of water content in biomass feedthe apparatus is very compact• A wide range of feedstock can be gasified• Possibility to use a catalyst as bed material (regeneration of catalyst in combustion zone) to influence the gas composition and gasification kinetic in a positive way

http://www.ficfb.at/

2.2.3. SilvaGas gasifiers (Rentech)

http://www.rentechinc.com/silvaGas.php

• One of the most mature gasifier technologies, commissioned plant un Burlington in 1984 is still in operation. Tested moisture content biomass ranges from 0% to 50% during >30,000 hours of plant operation in Vermont (182 tons of fry biomass fed per day)• A gasifier comprised of fluidized bed gasification reactor that produces a gas with a HVV up to 18.5 MJ/Nm³ (>15 MJ/m3) and nearly free of nitrogen. • The gasification process is based on an internally circulating fluidized bed system and consists of a gasification zone fluidized with steam and a combustion zone fluidized with air. It rapidly responds to downstream conditions. • The gasifier produces relatively low-tar syngas; the SilvaGas technology allows to combine it with different gas cleaning technologies.

Gasifier efficiencies (carbon conversion) rangeDr. Petr Dudin | 2012

http://www.rentechinc.com/silvaGas.php

Report: Review of Technologies for Gasification of Biomass and Wastes, 2009

Entrained Flow

Bubbling Fluidised Bed

Circulating Fluidised Bed

Twin-Bed

2.3. Gasifier type comparison


2.4. A typical gasification plant design.

• Gas cleaning (from tar, dust, ash) is essential before the produced gas can be used.

• There is a range of Gas scrubber technologies available

• Several CHP units allow flexibility when the gasifier is not fully loadedDr. Petr Dudin | 2012

2.5. Tar reforming and Scrubbing

Gas scrubber technologies

Dutch OLGA: Oil Gas Scrubber

• Oil absorbs the tar(BKW Güssing and MEVA)

Danish TARWATC• Condenses tar and the water in the gas.• Light and Heavy tars are separated• Discharge of contaminated water is the issue(Vølund Harboøre Technology)

Partial oxidation• Injected Oxygen oxidises the tar

Ctar + O2 → CO2

• Reduction in efficiency (Viking, Nexterra gasifiers )

Catalytic steam reformingCH4 + H2O ↔ CO + 3H2

Producer GasWith higher LHV


2.5.1. TARWATC cleaning technology scheme

• The contaminated waste water inlet for TARWATC may contain 15 – 20 g/litre of organic acids (causing an acidity about pH = 2), 5 – 10 g/litre of phenols (and similar compounds) and a total organic carbon content (TOC) of 40 – 50 g/litre. • The clean condensate from TARWATC has a TOC below 15 mg/litre, a total phenol content below 0.15 mg/litre and an acidity of pH = 6.90 – 7.10


2.5.2. OLGA cleaning technology scheme

• Invented by the Energy research Centre of the Netherlands (ECN) and further commertialized in collaboration with Royal Dahlmann.

• Goal of the OLGA technology is to lower the tar dew point to a level at which problems can be excluded.

• OLGA operates above the water dew point, but decreases the tar dew point to a level under the lowest process temperature. Tar & water are not mixed.

• Tars trapped by oil are returned to the gasifier and the oil returned back to the cleaning cycle.

http://www.renewableenergy.nl

OLGA stands for OiL GAs scrubbing technology


http://www.renewableenergy.nl/

CHP

Methanol production line

2.6. Cogeneration overview


• With generation capacity increase there is an increase in electrical efficiency, but a decrease in total efficiency (electrical + thermal efficiency).

• The increase in electrical efficiency occurs due to the fact that as the gas engine increases in size it receives a greater fraction of the gas generated in the gasifier.

• The total efficiency decreases with increasing generation capacity due to the difference between the conversion efficiencies of the thermal and electrical components in the plant.

• Electricity cannot be generated as efficiently as steam and with increasing electrical generation the fraction being produced at this lower conversion efficiency increases thus lowering the overall efficiency.

2.6.1. CHP efficiency general considerations


Sari Kilpimaa (University of Oulu) HighBio project seminar, 2011

• Wood gasified ash is a good liming agent due to its alkalinity

• Fertilising value of the gasified ash is questionable and typically is too low. In Finland ash is used as a fertiliser in forestry. Relatively high content of heavy metals can be an issue

• Depending on gasifier operation ash may contain different amount of (unreacted) carbon. Ashes with carbon content > 35% may be re-gasified, giving HHV > 15 MJ/kg

• Utilisation of such ash is feasible in building industry (asphalts, concrete, etc.). However, high alkalinity should be bore in mind.

2.7. Gasifier ash


plant Varnamo, SWEVarnamo

(upgraded) Güssing, AUT Alkmaar, NLBurlingron,

VermontTallahassee,

Florida Lahti, FinlandProcess Forester-Wheeler Forester-Wheeler REPOTEC / TUV MILENA SilvaGas SilvaGas Forester-Wheeler

type of gasifierCirculating fluidised

bed Circulating fluidised bedtwin-bed (Ni-olivine

catalyst) twin-bed gasifier twin-bed twin-bedCirculating Fluidised

Bed

gas cleaningCooler, hot-gas ceramic filters

HT filter (remove particulates), up-grading

(steam reforming) Cooler, filter, scrubber OLGAhot-gas conditioning

catalyst (DN34) OLGA

bag house filter equipped with

sorbent feedingGasification pressure,

bar 20 20 1 1 1 1 airTemperature, oC 950-1000 950-1000 900-1000 885 850-900 850-900 900Gasifier medium air O2/steam air/steam air/steam air/steam air/steam no data

H2, %v 9.5-12 32 38-45 18 17.5-22 no data (project) no dataCO, %v 16-19 27 22-26.6 44 44-50 no data (project) no data

CO2, %v 14.4-17.5 29 20-23 11 9.4-12.2 no data (project) no dataCH4, %v 5.8-7.5 8 9-12 15 15.6 no data (project) no data

C2> hydrocarbons, %v 2 3 2.5 1 >5 no data (project) no dataBenzene, %v 0.4 1 <1 no data - no data (project) no data

N2, %v 42-52 0 1.5 4 1-2 no data (project) no data

Tar (wet gas), g/mn3 8 8 1.. 2no data (presume,

eliminated) no data (project) no dataH2O, vol% wet 11 28 40 25 no data no data (project) no data

LHV (dry gas), MJ/m3 5-7 12.4 12-15 15 15.4-18.5 no data (project) 4.6-5.8

fuelflexible fuels (incl.

wood) flexible fuels (incl. wood)wood chips and wood

residues wood wood, crops, willow biomass cropswood and paper

wastewater content in a fuel 5-20% 5-20% 20-30% 10-25% 10-50% no data (project) no data

fuel input 18 MW 18 MW 10.4 10 53 109 160

engine type no data no data CHP CHP CHP (turbine)GAS Turbine + steam Turbine gas burners

Electricity Efficiency 32%bio-hydrogen production

focus 25% 37% (projected) no data 38% 34%

Total (net) efficiency 83%bio-hydrogen production

focus 56% 40% (projected) no data no data 65%comissioned 1997 2007 2002 2010 1999 2009 2006-2012plant power

Electricity/Heat, MW 6/8 6/8 2/8 11.6 (thermal) 41 (electr) 50/96

(capital) costs € 17 m additional € 27 m € 10 m 4000 € /MW $14 mproject was not

started € 100 m

2.8. Gasification plant technology comparison


CHP

Methanol production line

2.9. Bio-Methanol production

METHANOL SYNTHESIS: CO + 2H2 → CH3OH• Ideal mol ratio is 2(H2) to 1(CO)

• However, upgraded gas can contain H2/CO as much as 3/1 …4/1, which can be corrected by the water gas-shift reaction:

CO + 2H2O → CO2 + H2

• The cleaned and conditioned syngas is converted to methanol in a fixed bed reactor containing a copper/zinc oxide/alumina catalyst. • The mixture of methanol and unconverted syngas is cooled through heat exchange with the steam cycle and other process streams. • The methanol is separated by condensing it away from the unconverted syngas. • Unconverted syngas is recycled back to the entrance of the methanol synthesis reactorDr. Petr Dudin | 2012

2.9.1. Bio-Methanol production• NREL report (2012) projects production of - 365 tons a day of methanol- from 2000 tons of dry wood (4000 tons at 50% moisture content)- which is 1 ton of methanol from 5.5 tons of wood• The suggested wood-to-methanol (gasoline) plant scheme:


2.9.2. Methanol market

Prices: IHS Chemical weekly Global Methanol report (http://www.ihs.com/images/Global_Methanol_mar12.pdf)

Methanol is one of the most heavily traded ‘chemical commodities’. Its price is highly volatile and largely dependent on Oil/Nat.Gas prices. Methanol is used in synthesis of formaldehyde, acetic acid, methyl esters (DME), etc.Simple derivation of methanol price dependence on oil price gives a table

Spot sample time

PRICE RATIO$ ton methanol /

$ oil barrel

April 2009 3.7

Jan 2010 3.7

July 2011 3.1

June 2012 3.5

Long-term consideration (based on current pessimistic macroeconomic scenarios) for the price of crude oil dropping down to $60 per barrel would impact methanol market in turn. Projecting methanol price at $210 ($60 × 3.5).

This makes bio-methanol production even more attractive and sustainable source of income.

However, since China accounts for 40% of world methanol demand, a considerable shrinkage of the demand on the market is expected in a pessimistic scenario.


http://www.ihs.com/images/Global_Methanol_mar12.pdf

3.1. Model gasification plant

Model assumptions:• The plant capacity is based on the available supply of wood chips in a Gomel

region, which is 250,000 m3 per year

• The transport model assumes the wood chips will be available throughout the year and transported with 1 lorry for distances <50 km.

• Wood moisture content is 50% for the raw chips, which is the highest value.

14 $/m3


3.2. Gasification plant construction costs

• Typically, installation cost per $ per kWe decrease with increasing plant power. It is assumed, that drying and handling costs will be largely reduced, compared to such installations in W. Europe.

• A simple gasifier design is to be employed, in order to reduce the installation cost. This should, however, take into account the quality of the produced gas.

• Two scenarios considered where €12,000,000 and € 20,000,000 investment would be required:

i) 2.9 MWe plant (at 4.3 €/kWe) which would need 80,000 m3 of wood chips p.y. (case of Rechitsa county)

ii) 9 MWe (at 2.5 €/kWe) plant which would require 250,000 m3 wood chips p.y. (case of Gomel region)

Typical total installed capitals costs for a gasification plant per kWe (Knoef, 2005)

Plant location consideration:

• Plant should be constructed near the heat user, where generating power of the plant can be utilized.

• Ideal location would be next to a saw-mill, where heat can be utilized for drying wood throughout a year.

• Alternatively, a plant can be built in a location, where a production cluster, that uses heat (burns natural gas), can purchase heat.


3.3. Model parameters of a 3 MWe and 9 MWe gasification plantModel parameter Assumed value notes

Raw chips price per metric ton, USD $13.9 Fixed rate assumed

Exchange rate USD/BYR 8400 The exchange rate assumed to be flat throughout the analysis

Electricity cost (130% tariff), BYR 1034.3 The tariff rate assumed to be flat

Methanol cost p. ton , USD 400 The price is underestimated. Quick market analysis is presented above

CHP electrical efficiency 38% A medium efficiency is taken. Typical value is 38 ± 3 %CHP thermal efficiency 45% A rather low value is used in the modelGasifier efficiency 78% The value is taken as per Güssing plantDRY wood LHV, MJ/kg 18.3 HHV for dry wood is 20.3 MJ/kg

Wood chips moisture content 47% 50% value is in winter and 40% is in summer

Wood chips dried to moisture 15% This moisture content would produce the syngas with LHV 15.2 MJ/kg

Wood chips density at 47%, ton/m3 0.33 The value taken from the Ledzinsky’s report (2012)

Working days in a year, days 300 It is assumed the plant will be closed for maintenance and some delay in operation is allowed

Operating in a day, hours 24

Discount rate, % 7% S&P500 interest rate is considered

Electricity/heat consumed by the plant 7% / 10%

Maintenance costs 2.5% A typical value considered in other projectsDr. Petr Dudin | 2012

3.4. Sensitivity analysis

Economical analysis points out certain bottlenecks:

1) Optimization of the gasifier performance s crucial for the project success

2) Wood chips should be contracted at price lower than $14 per m3 to insure positive IRR

3) Plant installation costs vs. projected efficiency must to be considered before embarking the project

Two scenarios are considered

3 MWe / 3.5 MWth plant (€12 m investment)80,000 m3 wood chips required

9 MWe / 10 MWth plant (€22 m investment)250,000 m3 wood chips required

Just electricity sold(IRR = -18%)

Electricity sold + 50% heat sold as Natural Gas replacement

(IRR = -9 %)

Electricity sold + 50% heat sold as Natural Gas replacement

(IRR = 12 %)Just electricity sold(IRR = 4.3 %)

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wood chips cost

installation costs

operating days in a year

IRR

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VARIATION, %

Gasifier performance (wood LHV),electricity tariff, CHPe efficiency

IRR = 4.3 % over 10 years


1) Enterprise, selling only electricity to the grid becomes economically feasible if wood chips become available at a cost 16 $/m3, which can be ensured only by creating own supply-chain.

2) 9 MWe plant would require 250,000 m3 of wood chips, which would require ca. 72,000 tons of raw wood to be purchases and utilized per year. Alternative gasification fuels, such as peat should be considered to secure the supply.

3) Building a 3 MWe plant is unfeasible, since the investment cost would hardly meet the low wood prices and possibility of selling heat.

4) Sudden change in external policy, legislation and tariffs: electricity tariffs should be fixed at 0.16 $. Changes in USD/BYR exchange rate without alteration of tariffs would endanger the project.

5) Heat produced at the plant can be sold to a nearby customer. The heat value can be estimates as an alternative to natural gas (based on its HHV). Therefore, heat can be traded as a cheaper alternative to the natural gas. This can attract new industries (sawn-mills, OSB production, cattle farms) to settle aside.

6) Literature analysis shows that a major factor in the failure of the gasification plants was technical difficulties. The more complex plants encountered more problems. It is better to keep a plant relatively simple.

7) Bio-methanol production from the syngas is highly venturous, since the methanol prices are volatile and the initial equipment investment is significantly higher. The project becomes economically feasible if price for methanol would be > $350 per ton.

3.5. Risks


4. Summary

• 85,000 / 250,000 tons of raw wood chips (2.0 / 6.6 tons of dry wood elevated per hour) would allow running such a plant :

• 3 / 9 MWe (38% efficiency) plant power, with 18.3 / 60 GW-h of electricity produced annually

• 3.5 / 10 MWh (45% efficiency) heat power, with 22.5 / 73 GW-h of heat generated annually.

• 10,500 / 34,000 tons of methanol can be produced alternatively

• Generated heat power can be compared to that of obtained by burning natural gas. Annual heat produced is equivalent to burning 2,500,000 / 8,000,000 mn

3 of natural gas with (LHV=33 MJ/m3)

• Annual revenue from selling 21.7 GW-h electricity to the grid is $3,000,000 / $9,500,000 (7% is retained for plant’s operation)

• Market price for 10,500 / 34,000 tons of methanol is $4,320,000 / $13,700,00 ($400 per ton), which more compared to selling the electricity to the grid at 80% tariff ($1,900,00 / $8,100,000 annual revenue)

• IRR is -18% / 4.3% and the payback time is 5 years for the investment worth $14,500,000 / $26,600,000Dr. Petr Dudin | 2012

Feasibility study: Wood gasification power plant in Belarus (2012)

Engineering

Transcript of Feasibility study: Wood gasification power plant in Belarus (2012)