气氛及甲烷催化活化对流化床煤热解的影响
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摘要
为了提高煤热解焦油的产率和品质,在小型流化床实验台上分别考察了N_2,N_2+H_2,CH_4+N_2,CH_4+H_2等气氛及前置Ni/Al_2O_3催化剂对流化床煤热解的影响,结果表明:H_2气氛会减少半焦产率,增加焦油产率;CH_4气氛在800℃时反而会增加半焦产率,同时高温下CH_4的分解对焦油产率的增加有促进作用,相比于N_2气氛,焦油产率提高了35.8%;CH_4+H_2气氛下半焦焦油产率的总体趋势同H_2气氛下相同.还原性气氛有利于焦油的轻质化:H_2,CH_4+N_2,CH_4+H_2气氛下800℃时,轻质焦油的占比分别较N_2气氛提高了29.1%,15.2%,24%.在CH_4+N_2和CH_4+H_2气氛下,采用前置Ni/Al_2O_3催化剂后,焦油产率都得到不同程度的提升.CH_4+N_2气氛下600℃时,催化剂可以使焦油产率较无催化剂时提高40%;CH_4+H_2气氛下800℃时,催化剂对CH_4的催化效果更好,热解气中CH_4含量明显减少,而焦油产率较无催化剂时提高了37%.Ni/Al_2O_3催化剂可以进一步提高焦油的品质,并且有利于焦油中芳香烃的生成.
In order to improve the yield and quality of coal tar,the effects of atmosphere and Ni/Al_2O_3 catalyst on coal pyrolysis characters were investigated in a fluidized bed in H_2,CH_4,N_2 and mixed atmosphere.The results show that H_2 can reduce semicoke yield and increase tar yield;CH_4can increase semicoke yield at 800 ℃.Due to the decomposition of methane,compared with N_2 atmosphere,CH_4can increase tar yield by 35.8%.In CH_4+H_2atmosphere,semicoke and tar yield have the same trend with H_2 atmosphere.Reducing atmosphere is beneficial to improving the quality of the tar.In H_2,CH_4+N_2,CH_4+H_2 at mosphere,light tar ratio increases by 29.1%,15.2%,24%,respectively.The Ni/Al_2O_3 catalyst placed before the reaction segment can improve semicoke and tar yield to different degrees.At 600 ℃,compared with coal pyrolysis in CH_4 +N_2 atmosphere without catalyst,adding Ni/Al_2O_3 into CH_4 +N_2atmosphere increases tar yield by 40%.In CH_4 + H_2 atmosphere,the Ni/Al_2O_3 has better catalytic effect on CH_4 at 800 ℃,and CH_4 in the pyrolysis gas decreased significantly,meantime tar yield increases by 37% compared that of without catalyst.Ni/Al_2O_3 can further improve the quality of the tar and is beneficial to the formation of aromatic compounds.
In order to improve the yield and quality of coal tar,the effects of atmosphere and Ni/Al_2O_3 catalyst on coal pyrolysis characters were investigated in a fluidized bed in H_2,CH_4,N_2 and mixed atmosphere.The results show that H_2 can reduce semicoke yield and increase tar yield;CH_4can increase semicoke yield at 800 ℃.Due to the decomposition of methane,compared with N_2 atmosphere,CH_4can increase tar yield by 35.8%.In CH_4+H_2atmosphere,semicoke and tar yield have the same trend with H_2 atmosphere.Reducing atmosphere is beneficial to improving the quality of the tar.In H_2,CH_4+N_2,CH_4+H_2 at mosphere,light tar ratio increases by 29.1%,15.2%,24%,respectively.The Ni/Al_2O_3 catalyst placed before the reaction segment can improve semicoke and tar yield to different degrees.At 600 ℃,compared with coal pyrolysis in CH_4 +N_2 atmosphere without catalyst,adding Ni/Al_2O_3 into CH_4 +N_2atmosphere increases tar yield by 40%.In CH_4 + H_2 atmosphere,the Ni/Al_2O_3 has better catalytic effect on CH_4 at 800 ℃,and CH_4 in the pyrolysis gas decreased significantly,meantime tar yield increases by 37% compared that of without catalyst.Ni/Al_2O_3 can further improve the quality of the tar and is beneficial to the formation of aromatic compounds.
引文
[1]张存民.大力发展洁净煤技术,促进煤炭产业健康发展[J].中国煤炭,2016,42(4):22-24.ZHANG Cunmin.Vigorously Develop Clean Coal Technology,and Promote the Healthy Development of Coal Industry[J].China Coal,2016,42(4):22-24.
[2]岑建孟,方梦祥,王勤辉,等.煤分级利用多联产技术及其发展前景[J].化工进展,2011,30(1):88-94.CEN Jianmeng,FANG Mengxiang,WANG Qinhui,et al.Development and Prospect of Coal Staged Conversion Poly-generation Technology[J].Chemical Industry and Engineering Progress,2011,30(1):88-94.
[3]李保庆.我国煤加氢热解研究(Ⅱ):先锋褐煤加氢及催化加氢热解的热重研究[J].燃料化学学报,1995,23(2):186-191.LI Baoqing.Hydropyrolysis of Chinese Coals(Ⅱ):Thermogravimetic Study on Catalytic and Non-catalytic Hydropyrolysis of Xianfeng Lignite[J].Journal of Fuel Chemistry and Technology,1995,23(2):186-191.
[4]MAKINO M,TODA Y.Effects of Hydrogen Pressure on Hydrogasification of Taiheiyo(Japan)Coal[J].Fuel,1981,60(4):321-326.
[5]高梅杉,张建民,罗鸣,等.褐煤在甲烷气氛下热解特性及硫析出规律研究[J].煤炭转化,2005,28(4):7-10.GAO Meishan,ZHANG Jianmin,LUO Ming,et al.Study of Weight Loss Characters and Promoting Function to Sulfur Release During Lignite Pyrolysis in Methane[J].Coal Conversion,2005,28(4):7-10.
[6]张晓方,金玲,熊燃,等.热分解气氛对流化床煤热解制油的影响[J].化工学报,2009,60(9):2299-2307.ZHANG Xiaofang,JIN Ling,XIONG Ran,et al.Effect of Reaction Atmosphere on Tar Production from Coal Pyrolysis in Fluidized Bed Reactor[J].CIESC Journal,2009,60(9):2299-2307.
[7]廖洪强,孙成功,李保庆,等.富氢气氛下煤热解特性的研究[J].燃料化学学报,1998,26(2):114-118.LIAO Hongqiang,SUN Chenggong,LI Baoqing,et al.Coal Pyrolysis Under Hydrogen-rich Gases[J].Journal of Fuel Chemistry and Technology,1998,26(2):114-118.
[8]何涛,马晓迅,罗进成,等.铜川煤催化加氢热解行为的研究[J].煤炭转化,2008,31(2):4-7.HE Tao,MA Xiaoxun,LUO Jincheng,et al.Study on Catalytic Hydropyrolysis of Tongchuan Coal[J].Coal Conversion,2008,31(2):4-7.
[9]闫伦靖,孔晓俊,白永辉,等.Mo和Ni改性的HZSM-5催化剂对煤热解焦油的改质[J].燃料化学学报,2016,44(1):30-36.YAN Lunjing,KONG Xiaojun,BAI Yonghui,et al.Catalytic Upgrading of Gaseous Tar from Coal Pyrolysis over Mo and Nimodified HZSM-5[J].Journal of Fuel Chemistry and Technology,2016,44(1):30-36.
[10]CHAREONPANICH M,ZHANG Zhanguo,NISHIJIMA A,et al.Effect of Catalysts on Yields of Monocyclic Aromatichydrocarbons in Hydrocracking of Coal Volatile Matter[J].Fuel,1995,74(11):1636-1640.
[11]李敏.富氢气氛下煤催化热解特性研究[D].杭州:浙江大学,2015.LI Min.Studies on Coal Catalytic Pyrolysis Characteristics During Hydrogen-rich Atmosphere[D].Hangzhou:Zhejiang University,2015.
[12]高超,马凤云,马空军,等.热解气氛对煤催化热解焦油品质的影响[J].煤炭学报,2015,40(8):1956-1962.GAO Chao,MA Fengyun,MA Kongjun,et al.Effect of Pyrolysis Gas on the Tar Quality from Coal Catalytic Pyrolysis[J].Journal of China Coal Society,2015,40(8):1956-1962.
[13]刘全润.煤的热解转化和脱硫研究[D].大连:大连理工大学,2005.LIU Quanrun.Coal Conversion and Desulfurization During Pyrolysis[D].Dalian:Dalian University of Technology,2005.
[14]LIU Jiahe,HU Haoquan,JIN Lijun,et al.Integrated Coal Pyrolysis with CO2Reforming of Methane over Ni/MgO Catalyst for Improving Tar Yield[J].Fuel Processing Technology,2010,91(4):419-423.
[15]BRAEKMAN-DANHEUX C,CYPRES R,FONTANA A,et al.Coal Hydromethanolysis with Coke-oven Gas(1):Influence of Temperature on the Pyrolysis Yields[J].Fuel,1992,71(3):251-255.
[16]BRAEKMAN-DANHEUX C,CYPRES R,FONTANA A,et al.Coal Hydromethanolysis with Coke-oven Gas(2):Influence of the Coke-oven Gas Components on Pyrolysis Yields[J].Fuel,1995,74(1):17-19.
[17]MA Zhichao,MA Xiaoxun,LUO Jincheng,et al.Catalytic Hydropyrolysis of Five Chinese Coals[J].Energy and Fuels,2012,26(1):511-517.
[18]陈磊,金晶,索娅,等.甲烷浓度对天然气与煤共热解的影响[J].锅炉技术,2010,41(5):1-4.CHEN Lei,JIN Jing,SUO Ya,et al.Effects of Methane Concentration of Co-gasification of Coal and Methane[J].Boiler Technology,2010,41(5):1-4.
[19]LI Baoqing,BRAEKMAN-DANHEUX C,CYPRES R.Catalytic Hydropyrolysis by Impregnated Sulfided Mo Catalyst[J].Fuel,1991,70(2):254-258.
[20]张国杰,张永发,张猛,等.半焦炭催化甲烷裂解及动力学特性[J].现代化工,2009,29(1):29-32.ZHANG Guojie,ZHANG Yongfa,ZHANG Meng,et al.Methane Decomposition over Carbonaceous Catalyst and Its Kinetic Characteristics[J].Modern Chemical Industry,2009,29(1):29-32.
[21]郝瑛轩,刘全润,李国亮,等.微波辐照下半焦催化甲烷裂解制氢研究[J].煤炭转化,2014,37(4):64-68.HAO Yingxuan,LIU Quanrun,LI Guoliang,et al.Catalytic Methane Decomposition over Coal Char Under Microwave Irradiation[J].Coal Conversion,2014,37(4):64-68.
[22]SUO Ya,ZHANG Jianmin,LIAN Hui,et al.Effects of Methane Concentration on Hydrocarbon Release During the Pyrolysis of Coal[J].Korean Journal of Chemical Engineering,2007,24(2):328-331.
[23]KUIJPERS E,BREEDIJK A K,VANDERWAL W,et al.Chemisorption of Methane on Ni/SiO2Catalysts and Reactivity of the Chemisorption Products Toward Hydrogen[J].Journal of Catalysis,1983,81(2):429-439.
[24]周引穗,焦博,高爱华,等.甲烷直流放电等离子体中氢自由基形成规律研究[J].西北大学学报(自然科学版),2006,36(4):540-542.ZHOU Yinsui,JIAO Bo,GAO Aihua,et al.Investigation on the Rule of Hydrogen Free Radical form Action in Methane DC Discharge Plasma[J].Journal of Northwest University(Natural Science Edition),2006,36(4):540-542.
[25]KOHN D W,CLAUBERG H,CHEN P.Flash Pyrolysis Nozzle for Generation of Radicals in a Supersonic Jet Expansion[J].Review of Scientific Instruments,1992,63(8):4003-4005.
[26]刘兆祥,李润君,陆建江,等.高温瞬时热解法产生甲基自由基束[J].高等学校化学学报,1995,16(7):1114-1115.LIU Zhaoxiang,LI Runjun,LU Jianjiang,et al.Methyl Free Racial Beam Generated by Flash Pyrolysis Method[J].Chemical Journal of Chinese University,1995,16(7):1114-1115.
[27]ZHANG Tiejun,AMIRIDIS M D.Hydrogen Production via the Direct Cracking of Methane over Silica-supported Nickel Catalysts[J].Applied Catalysis A,1998,167(2):161-172.
[28]代斌,陈韩飞,洪成林,等.脉冲电晕等离子体作用下CH4/H2反应的机理[J].化学研究与应用,2007,19(7):770-774.DAI Bin,CHEN Hanfei,HONG Chenglin,et al.Mechanism of CH4/H2Conversion Under Pulse Corona Plasma[J].Chemical Research and Application,2007,19(7):770-774.
[29]MA Zhihua,ZHU Zibin,ZHANG Chengfang,et al.Flash Hydropyrolysis of Zalannoer Lignite[J].Fuel Processing Technology,1994,38(2):99-109.
[2]岑建孟,方梦祥,王勤辉,等.煤分级利用多联产技术及其发展前景[J].化工进展,2011,30(1):88-94.CEN Jianmeng,FANG Mengxiang,WANG Qinhui,et al.Development and Prospect of Coal Staged Conversion Poly-generation Technology[J].Chemical Industry and Engineering Progress,2011,30(1):88-94.
[3]李保庆.我国煤加氢热解研究(Ⅱ):先锋褐煤加氢及催化加氢热解的热重研究[J].燃料化学学报,1995,23(2):186-191.LI Baoqing.Hydropyrolysis of Chinese Coals(Ⅱ):Thermogravimetic Study on Catalytic and Non-catalytic Hydropyrolysis of Xianfeng Lignite[J].Journal of Fuel Chemistry and Technology,1995,23(2):186-191.
[4]MAKINO M,TODA Y.Effects of Hydrogen Pressure on Hydrogasification of Taiheiyo(Japan)Coal[J].Fuel,1981,60(4):321-326.
[5]高梅杉,张建民,罗鸣,等.褐煤在甲烷气氛下热解特性及硫析出规律研究[J].煤炭转化,2005,28(4):7-10.GAO Meishan,ZHANG Jianmin,LUO Ming,et al.Study of Weight Loss Characters and Promoting Function to Sulfur Release During Lignite Pyrolysis in Methane[J].Coal Conversion,2005,28(4):7-10.
[6]张晓方,金玲,熊燃,等.热分解气氛对流化床煤热解制油的影响[J].化工学报,2009,60(9):2299-2307.ZHANG Xiaofang,JIN Ling,XIONG Ran,et al.Effect of Reaction Atmosphere on Tar Production from Coal Pyrolysis in Fluidized Bed Reactor[J].CIESC Journal,2009,60(9):2299-2307.
[7]廖洪强,孙成功,李保庆,等.富氢气氛下煤热解特性的研究[J].燃料化学学报,1998,26(2):114-118.LIAO Hongqiang,SUN Chenggong,LI Baoqing,et al.Coal Pyrolysis Under Hydrogen-rich Gases[J].Journal of Fuel Chemistry and Technology,1998,26(2):114-118.
[8]何涛,马晓迅,罗进成,等.铜川煤催化加氢热解行为的研究[J].煤炭转化,2008,31(2):4-7.HE Tao,MA Xiaoxun,LUO Jincheng,et al.Study on Catalytic Hydropyrolysis of Tongchuan Coal[J].Coal Conversion,2008,31(2):4-7.
[9]闫伦靖,孔晓俊,白永辉,等.Mo和Ni改性的HZSM-5催化剂对煤热解焦油的改质[J].燃料化学学报,2016,44(1):30-36.YAN Lunjing,KONG Xiaojun,BAI Yonghui,et al.Catalytic Upgrading of Gaseous Tar from Coal Pyrolysis over Mo and Nimodified HZSM-5[J].Journal of Fuel Chemistry and Technology,2016,44(1):30-36.
[10]CHAREONPANICH M,ZHANG Zhanguo,NISHIJIMA A,et al.Effect of Catalysts on Yields of Monocyclic Aromatichydrocarbons in Hydrocracking of Coal Volatile Matter[J].Fuel,1995,74(11):1636-1640.
[11]李敏.富氢气氛下煤催化热解特性研究[D].杭州:浙江大学,2015.LI Min.Studies on Coal Catalytic Pyrolysis Characteristics During Hydrogen-rich Atmosphere[D].Hangzhou:Zhejiang University,2015.
[12]高超,马凤云,马空军,等.热解气氛对煤催化热解焦油品质的影响[J].煤炭学报,2015,40(8):1956-1962.GAO Chao,MA Fengyun,MA Kongjun,et al.Effect of Pyrolysis Gas on the Tar Quality from Coal Catalytic Pyrolysis[J].Journal of China Coal Society,2015,40(8):1956-1962.
[13]刘全润.煤的热解转化和脱硫研究[D].大连:大连理工大学,2005.LIU Quanrun.Coal Conversion and Desulfurization During Pyrolysis[D].Dalian:Dalian University of Technology,2005.
[14]LIU Jiahe,HU Haoquan,JIN Lijun,et al.Integrated Coal Pyrolysis with CO2Reforming of Methane over Ni/MgO Catalyst for Improving Tar Yield[J].Fuel Processing Technology,2010,91(4):419-423.
[15]BRAEKMAN-DANHEUX C,CYPRES R,FONTANA A,et al.Coal Hydromethanolysis with Coke-oven Gas(1):Influence of Temperature on the Pyrolysis Yields[J].Fuel,1992,71(3):251-255.
[16]BRAEKMAN-DANHEUX C,CYPRES R,FONTANA A,et al.Coal Hydromethanolysis with Coke-oven Gas(2):Influence of the Coke-oven Gas Components on Pyrolysis Yields[J].Fuel,1995,74(1):17-19.
[17]MA Zhichao,MA Xiaoxun,LUO Jincheng,et al.Catalytic Hydropyrolysis of Five Chinese Coals[J].Energy and Fuels,2012,26(1):511-517.
[18]陈磊,金晶,索娅,等.甲烷浓度对天然气与煤共热解的影响[J].锅炉技术,2010,41(5):1-4.CHEN Lei,JIN Jing,SUO Ya,et al.Effects of Methane Concentration of Co-gasification of Coal and Methane[J].Boiler Technology,2010,41(5):1-4.
[19]LI Baoqing,BRAEKMAN-DANHEUX C,CYPRES R.Catalytic Hydropyrolysis by Impregnated Sulfided Mo Catalyst[J].Fuel,1991,70(2):254-258.
[20]张国杰,张永发,张猛,等.半焦炭催化甲烷裂解及动力学特性[J].现代化工,2009,29(1):29-32.ZHANG Guojie,ZHANG Yongfa,ZHANG Meng,et al.Methane Decomposition over Carbonaceous Catalyst and Its Kinetic Characteristics[J].Modern Chemical Industry,2009,29(1):29-32.
[21]郝瑛轩,刘全润,李国亮,等.微波辐照下半焦催化甲烷裂解制氢研究[J].煤炭转化,2014,37(4):64-68.HAO Yingxuan,LIU Quanrun,LI Guoliang,et al.Catalytic Methane Decomposition over Coal Char Under Microwave Irradiation[J].Coal Conversion,2014,37(4):64-68.
[22]SUO Ya,ZHANG Jianmin,LIAN Hui,et al.Effects of Methane Concentration on Hydrocarbon Release During the Pyrolysis of Coal[J].Korean Journal of Chemical Engineering,2007,24(2):328-331.
[23]KUIJPERS E,BREEDIJK A K,VANDERWAL W,et al.Chemisorption of Methane on Ni/SiO2Catalysts and Reactivity of the Chemisorption Products Toward Hydrogen[J].Journal of Catalysis,1983,81(2):429-439.
[24]周引穗,焦博,高爱华,等.甲烷直流放电等离子体中氢自由基形成规律研究[J].西北大学学报(自然科学版),2006,36(4):540-542.ZHOU Yinsui,JIAO Bo,GAO Aihua,et al.Investigation on the Rule of Hydrogen Free Radical form Action in Methane DC Discharge Plasma[J].Journal of Northwest University(Natural Science Edition),2006,36(4):540-542.
[25]KOHN D W,CLAUBERG H,CHEN P.Flash Pyrolysis Nozzle for Generation of Radicals in a Supersonic Jet Expansion[J].Review of Scientific Instruments,1992,63(8):4003-4005.
[26]刘兆祥,李润君,陆建江,等.高温瞬时热解法产生甲基自由基束[J].高等学校化学学报,1995,16(7):1114-1115.LIU Zhaoxiang,LI Runjun,LU Jianjiang,et al.Methyl Free Racial Beam Generated by Flash Pyrolysis Method[J].Chemical Journal of Chinese University,1995,16(7):1114-1115.
[27]ZHANG Tiejun,AMIRIDIS M D.Hydrogen Production via the Direct Cracking of Methane over Silica-supported Nickel Catalysts[J].Applied Catalysis A,1998,167(2):161-172.
[28]代斌,陈韩飞,洪成林,等.脉冲电晕等离子体作用下CH4/H2反应的机理[J].化学研究与应用,2007,19(7):770-774.DAI Bin,CHEN Hanfei,HONG Chenglin,et al.Mechanism of CH4/H2Conversion Under Pulse Corona Plasma[J].Chemical Research and Application,2007,19(7):770-774.
[29]MA Zhihua,ZHU Zibin,ZHANG Chengfang,et al.Flash Hydropyrolysis of Zalannoer Lignite[J].Fuel Processing Technology,1994,38(2):99-109.