Allothermal Gasification Of High Ash Coals

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Allothermal gasification ofhigh ash coalsC.M. van der MeijdenMarch 2014ECN-L--14-002

Allothermal gasificationof high ash coalsChristiaan van der Meijden12th European Gasification ConferenceRotterdam

Content Something about ECNFluidized Bed GasificationAllothermal GasificationECN MILENA for biomass gasificationECN i-MILENA for high ash coal gasificationTest resultsPromising configurations / applicationsFurther development of the i-MILENA for high ash coalConclusions / outlook

Position independent connecting esearchappliedresearchindustrialdevelopment

Fluidized Bed Gasifcation Proven technologyTypical 850 C - 1000 C, pressurization possible.Air blown or steam / oxygen mixtures.Scale 5 MWth.Hydrocarbons in the gas, some tar in gas.Fuel flexible (also used for waste and biomass)No fine milling required.Incomplete fuel conversion.Examples: ThyssenKrupp HTW, TRIG, U gas – SES.Better suitable for high ash coals then EFIn competition with fixed bed.GasFuelAirAsh4

Allothermal Gasificationcombustion: air (l 1) flue gas heatPyrolysis / gasification:fuel heat gas char allothermal gasification:fuel air (l 0.3) gas flue gaselectricity, heat, fuels, SNG,chemicals, H2, products

ECN MILENA BiomassGasification process Fluidized bed gasification Temperature level: 850 C Product gas contains methane, ethylene,benzene and tars Complete conversion of the fuel No carbon in the ash High efficiency Very little nitrogen in producer gas Heat transfer through bed material One single vessel: compact design Fuel flexible: wood, RDF, lignite, sunflowerhusks, etc.

Present status MILENA forbiomass gasification Lab-scale installation since 2004, Pilot plant since 2008Several demonstration projects in preparation: Alkmaar Bio-Methane demonstration ETI – RDF gasification, 1st phase (pilot plant tests) finalized India, 1 MWe gas engine (MILENA gasifier OLGA tar removal), underconstruction

i-MILENA for high ash coal

i-MILENA gasifier for high ash coali-MILENAFlue gas to coolerand stackSteamcombustionairSolidsGas SolidsHigh ash coalProducer gas to gascleaning

Tests Extensive testing done in 2012 & 2013 as part of the Optimash projectSeveral high ash coals testedAsh content over 50%Ash of coal used as bed materialGasifier connected to gas cleaning section (OLGA)

Measurement data using highash coal ( 50 wth% ash)

Measurement data using highash coal ( 50 wth% ash)01-05-201202-05-2012CO (vol%)17.814.9H2 (vol%)47.248.3CO2 (vol%)28.128.5CH4 (vol%)5.16.0N2 (vol%)2.72.6C2Hy (vol%)0.71.3C6H6 & C7H8 (ppmv)29003200H2S & COS (ppmv)40504900(mg/Nm3)n.m.9066Combustor temp. ( C)903889Gasifier temp. ( C)888853O2 combustor (vol%)3.22.5CO2 combustor (vol%)14.616.1Tar

Bottom ash

Foreseen applications (Co-)firing in boilers, scale 1 MWth. Gas engines for combined heat and power production, limited tar removalrequired, scale 2 – 20 MWe. Combined Cycles using gas turbines for power production, tar removalrequired, scale 6 MWe. SNG production, preferably in combination with CCS, tar removal required,scale 100 MWth.

Conclusions & Outlook: Tests showed that the i-MILENA is able to produce a medium calorificvalue producer gas without the need for an air separation unit (ASU). The overall carbon conversion is close to 100% (grey / white ash) Operated at low temperature, no ash melt. Simple gasifier, also suitable for small scale applications ( 100 MW), lowinvestment cost. High overall efficiency because of low operating temperature andcomplete conversion. CGE approx. 70%, which is relatively high for lowgrade coal. Next step in development: Pilot scale durations tests and preparations fordemo plant with commercial partner.

THANKS FOR THE ATTENTIONContact: Christiaan van der MeijdenECNWesterduinweg 31755 LE PettenThe NetherlandsP.O. Box 11755 ZG PettenThe NetherlandsT 31 224 56 45 82M 31 s: composition database: www.phyllis.nltar dew point calculator: www.thersites.nlIEA bioenergy/gasification: www.ieatask33.orgMilena indirect gasifier: www.milenatechnology.comOLGA: / www.renewableenergy.nlSNG: /www.bioCNG.com16

ECNWesterduinweg 31755 LE PettenThe NetherlandsT 31 88 515 4949F 31 88 515 [email protected] ecn.nlwww.ecn.nl8P.O. Box 11755 LG PettenThe Netherlands