运用Gibbs自由能最小化方法模拟气流床煤气化炉

274200410COALCONVERSIONVol.27No.4Oct.2004*(2003AA521020)(03QF14013).1);2);3);4),,200237:2004-07-15;:2004-08-25运用Gibbs自由能最小化方法模拟气流床煤气化炉*汪　洋1)　代正华2)　于广锁3)　于遵宏4)　基于AspenPlus工业系统流程模拟软件,运用Gibbs自由能最小化方法建立了气流床煤气化炉的模型.研究了气化炉的主要操作参数(即水煤浆浓度、氧煤比、碳转化率和气化温度)对气化结果的影响.对模拟结果进行了分析,发现模型基本正确,可应用于一些反应机理复杂的气化工艺的化学和热力学平衡计算.模拟结果表明,氧煤比和水煤浆浓度是影响气化炉出口煤气组成的主要因素,气化炉温度随着氧煤比的增加而增加,也随着水煤浆浓度的增加而增加.结果还表明,氧煤比对气化结果的影响比水煤浆浓度的影响更为显著.　气流床,气化炉,Gibbs自由能,AspenPlus　TQ5450　引　言.,.[1],,4.Watkinson[2],,.Ruprecht[3],.,,,.,.,.,.[4].AspenPlus,,AspenPlus,.,AspenPlus.AspenPlus,AspenPlus,AspenPlus.AspenPlus,.AspenPlusFortranExcelCAPE-OPENCOM4.AspenPlus,Gibbs.AspenPlus10.2,.[5-7]1　气流床煤气化炉模型Gibbs1,392.DecompBurn,BurnGibbs,Separate,.[8]Coal,Inburner,Qtransfe,Water,Oxygen,Qlost,Mixture,Water1,Water2,Rawgas,Liquid.1Fig.1Diagramofentrained-flowbedcoalgasifiermodelDecomp,AspenPlus10.2Ryield.Decomp,Burn.,.(1),Q.(2).Ll=1mlH0f,feed,298+Ll=1mlH(Tfeed,l)=Ni=1niH0f,prod,298+Li=1niH(Tprod)+Q(1)H0f,coal,298=HHV-(327.63Car+1417.92Har+92.57Sar+158.67Mar)(2)BurnGibbs,AspenPlus10.2Rgibbs.,C,H,O,NS,:H2O,N2,O2,S,H2,Cl2,HCl,C(),CO,CO2,H2S,COS,CH4,H3N,CHN,15.Gibbs.(3)(4).minG,G=Sj=1G0jncj+Cj=S+1Pl=1Gjlnjl(3)S.t.bk=Sj=1mjkncj+Cj=S+1Pl=1mjknjlk=1,,E(4-1)Ll=1mlH0f,feed,298+Ll=1mlH(Tfeed,l)=Ni=1niH0f,prod,298+Li=1niH(Tprod)+Q(4-2)ni0(4-3)(3),S,,P,C.(4-1),E,mjk;(4-2),Q;(4-3).[9][10],RandNasaPowell's,Rand.RandLagrange,Newton-Raphson.Separate,AspenPlus10.2Flash2..2　模型的检验,282004291.1Table1UltimateandproximateanalysisofBeisucoalCHNSOA69.274.561.283.608.0813.21(5)Boie,.chdmi=[a1iwdmC,i+a2iwdmH,i+a3iwdmSt,i+a4iwdmO,i+a5iwdmN,i]102+a6i(5)Burn().Burn3(Inburner,WaterOxygen),(QtransfeQlost),Burn1(Mixture).:75033kg/h,64%(wt),30375m3/h,4.0MPa(G),98%,0.5%.2(Qtransfe-1.6069E+11J/h,Qlost-6.25E+9J/h).2Table2InformationofinletandoutletstreamsStreamnameInburnerWaterOxygenMixturePressure/MPa4.006.006.004.00Temperature/1000.050.025.01391.1Substream:MixedMoleFlow/(kmolh-1)H21086.254001361.901CO0002154.104CO2000557.0265H2S00051.01313COS0002.749543CH40000.189379N221.9418900.40680422.30928AR005.0172545.017254H3N0000.072922CHN0005.92E-03HCOOH0008.56E-03HCl0000.135451O2121.257601350.5911.78E-08H2O206.81151292.57201172.156S53.76268000Cl20.067725000Totalflow/(kmolh-1)1490.0951292.5721356.0155326.689Enthalpy/(Jmol-1)6.61E+06-2.84E+08-7.75E-07-9.00E+07Substream:CIPSDMoleflow/(kmolh-1)C2714.084Enthalpy/(Jkmol-1)1.79E+07Substream:NCPSDMassflow/(kgh-1)ASH7008.8577008.857Enthalpy/(Jkg-1)2.24E+057.93E+051)(1)C:2714.084kmol/h:2154.104+557.0265+2.749543+0.189379+5.92E-03+8.56E-03=2714.084(kmol/h)(2)H:1086.254+206.8115+1292.572=2585.638(kmol/h):1361.901+51.01313+0.1893792+0.0729221.5+(5.92E-03)0.5+8.56E-03+0.1354510.5+1172.156=2585.638(kmol/h)(3)O:121.25762+206.8115+1292.572+1350.5912=4443.081(kmol/h):2154.104+557.02652+2.749543+(8.56E-03)2+1.78E-08+1172.156=4443.080(kmol/h)294Gibbs.,[11]::K-1p,methanation=Kpms=p3H2pCOpCH4pH2O(6-1)lnKpms=-22632.81147/T+8.771694lnT-5.31482010-3T+5.13857610-7T2+4.28938710-12T3-29.878849(6-2):Kp,conversion=Kpwgs=pH2pCO2pCOpH2O(7-1)lnKpwgs=5041.399446/T-0.158666lnT+1.80725810-3T-4.88638610-7T2+5.99947010-11T3-4.991881(7-2):p=4.1MPa,T=1644.24K,H2=0.2557,CO=0.4044,CO2=0.1046,CH4=3.56E-5,H2O=0.2201:p3H2pCOpCH4pH2O=1.45106Kpms=1.44106:pH2pCO2pCOpH2O=0.300Kpwgs=0.299,.2):1490.095(6.61E+06)+2714.084(1.79E+07)+7008.857(2.24E+05)+1292.572(-2.84E+08)+1356.015(-7.75E-07)-1.6069E+11-6.25E+9=-4.738E+11(J/h):5326.689(-9.00E+07)+7008.857(2.24E+05)=-4.738E+11(J/h),.,.3　操作参数对气化结果的影响3.160%66%,3.,0.90,98%,0.5%,4.0MPa(G).,,.:,T,CO(CO+H2),H2,CO2H2O.,:,,,.,,H2,,,,,,H2,.COCO2,CO,CO2.[12],,,CO,H2.,1%(wt),25.3Table3Effectofcoal/watermassratioincoalslurryongasificationresultsCoal/watermassratioincoalslurry/%Wetbasiscomposition/mol%Drybasiscomposition/mol%H2COCO2H2OCO+H2Effectivegasproductiverate/(m3kg-1,drycoal)Temperature/6026.0536.6811.7124.1182.651.63951289.36225.8038.5811.0723.0683.671.63991340.36425.5740.4410.4622.0084.631.64011391.06625.3642.269.8720.9585.531.64021441.43020043.2,(kg/kg)0.900.96,4.,,.23,,H2CO,CO2H2O.,,,.,,,,,COH2,CO2,.,,,H2,.,0.01,30.3.3,90%98%,5.,,,,,,H2CO,CO2H2O.2Fig.2Effectofoxygen/coalmassratioongasificationresults3Fig.3Effectofoxygen/coalmassratioongasificationtemperatureandeffectivegasproductiverate4Table4Effectofoxygen/coalmassratioongasificationresultsOxygen/coalmassratio/(kgkg-1)Wetbasiscomposition/mol%Drybasiscomposition/mol%H2COCO2H2OCO+H2Effectivegasproductiverate/(m3kg-1,drycoal)Temperature/0.9025.5740.4410.4620.0084.631.64011390.80.9224.5640.3310.5723.0284.291.61231451.50.9423.5840.1810.7124.0083.901.58441511.30.9622.6340.0110.8824.9683.461.55641570.35Table5EffectofcarbonconversionrateongasificationresultsCarbonconversionrate/%Wetbasiscomposition/mol%Drybasiscomposition/mol%H2COCO2H2OCO+H2Effectivegasproductiverate/(m3kg-1,drycoal)Temperature/9022.7237.4811.2826.9382.381.43371540.79223.4438.2611.0525.6783.011.48541503.59424.1639.0110.8424.4383.591.53701466.19624.8739.7410.6423.2184.131.58861428.69825.5740.4410.4622.0184.631.64011391.1314Gibbs3.4,,.02.0%,6.,,CO2,COH2,,,,CO2H2,H2,CO2,