生物炭负载Ca和Fe催化玉米秸秆热解挥发分重整提高产气率
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摘要
为提升生物质炭对生物质热解挥发分的催化重整作用,以Fe_2O_3和CaO作为添加剂制备生物炭-Fe和生物炭-Ca催化剂对两者的催化重整能力进行了试验探讨。试验结果表明:无添加时的生物质炭对玉米秸秆颗粒热解挥发分催化作用明显,800℃时,液相产率较未使用催化剂时减少38.71%,最低可达21.49%。生物炭-Fe催化剂颗粒在800℃时液相产率下降至20.24%,产气率升至51.44%,同时,H2的体积分数增加,热解油中的有机物质被有效抑制;生物炭-Ca催化剂在800℃时液相产率和产气率分别为20.01%和51.96%。生物炭-Ca催化剂可以促进热解气中CH4的生成,降低CO2的体积分数。在本试验条件下,炭基催化剂对生物质热解挥发分催化重整的活性顺序依次为:生物炭-Ca>生物炭-Fe>生物质炭>无催化剂。
In order to improve the catalytic function of biochar on the pyrolysis volatiles of corn straw,biochar-Fe and biochar-Ca catalyst particles pyrolyzed from corn straw particles with Fe2 O3 and CaO additives.Then the catalytic reforming ability of the different catalysts(no catalyst,biochar,biochar-Fe and biochar-Ca) were tested and discussed.The results showed that the liquid yield of corn straw particles reached the lowest value of 35.06% and the highest gas yield of 36.95% at the temperature of 800 ℃ without catalyst;The liquid products of corn straw particles mainly consisted of organic compounds such as acids,aldehydes,alcohols,phenols,ethers and lipids;The components of pyrolysis gas mainly include CH4,CnH m,CO,CO2 and H2.It was obvious that the biochar catalyst particles influenced the pyrolysis volatile matter of corn straw particles.Compared with the treatment without catalyst,the liquid yield of treatment with biochar catalyst particles decreased,the lowest was 21.49%;the gas yield increased,and the highest value was 50.72%.Biochar-Fe catalyst particles play an important role in the high temperature condition and especially at 800 ℃,the liquid phase yield reached the lowest value of 20.24% and the gas yield was 51.44%.By adding biochar-Fe,the volume fraction of H2 in the gas product increased,and the volume fraction of H2 in the gas product was 28.39% at 800℃,which was higher than that in the pyrolysis gas of corn straw without using catalyst under the same conditions at 12.52 percent point.Moreover,biochar-Fe catalyst particles contributed to stop the formation of macromolecule organic matter in pyrolysis oil;Fe can be used as a good additive to produce hydrogen-rich gas at high temperature.A good catalytic reforming effect on the liquid phase substances in the volatile matter of corn straw pyrolysis at various temperatures was obtained at treatment with biochar-Ca catalyst particles.The liquid yield and gas yield reached the optimum values of 20.01% and 51.96% at 800 ℃ with biochar-Ca catalyst particles,so the biochar-Ca catalyst could promote the formation of CH4 gas with high calorific value in pyrolysis gas,which could reach 12.69% under the optimum experimental conditions,and reduced the volume fraction of CO_2,the lowest value of CO_2 was 30.25%.Ca O could be used as a good acceptor of CO_2 to produce high calorific value fuel gas.By using the method of variance analysis,it was found that the P value of different kinds of catalyst was 4.9×10~(-6),which indicated that different kinds of catalysts had a very significant effect on the pyrolysis oil of corn straw particles.According to the analysis of liquid phase yield and gas yield,the order of activity of biochar-based catalysts for the catalytic reforming of corn straw pyrolysis volatiles was biochar-Ca > biochar-Fe > biochar > no catalyst.
In order to improve the catalytic function of biochar on the pyrolysis volatiles of corn straw,biochar-Fe and biochar-Ca catalyst particles pyrolyzed from corn straw particles with Fe2 O3 and CaO additives.Then the catalytic reforming ability of the different catalysts(no catalyst,biochar,biochar-Fe and biochar-Ca) were tested and discussed.The results showed that the liquid yield of corn straw particles reached the lowest value of 35.06% and the highest gas yield of 36.95% at the temperature of 800 ℃ without catalyst;The liquid products of corn straw particles mainly consisted of organic compounds such as acids,aldehydes,alcohols,phenols,ethers and lipids;The components of pyrolysis gas mainly include CH4,CnH m,CO,CO2 and H2.It was obvious that the biochar catalyst particles influenced the pyrolysis volatile matter of corn straw particles.Compared with the treatment without catalyst,the liquid yield of treatment with biochar catalyst particles decreased,the lowest was 21.49%;the gas yield increased,and the highest value was 50.72%.Biochar-Fe catalyst particles play an important role in the high temperature condition and especially at 800 ℃,the liquid phase yield reached the lowest value of 20.24% and the gas yield was 51.44%.By adding biochar-Fe,the volume fraction of H2 in the gas product increased,and the volume fraction of H2 in the gas product was 28.39% at 800℃,which was higher than that in the pyrolysis gas of corn straw without using catalyst under the same conditions at 12.52 percent point.Moreover,biochar-Fe catalyst particles contributed to stop the formation of macromolecule organic matter in pyrolysis oil;Fe can be used as a good additive to produce hydrogen-rich gas at high temperature.A good catalytic reforming effect on the liquid phase substances in the volatile matter of corn straw pyrolysis at various temperatures was obtained at treatment with biochar-Ca catalyst particles.The liquid yield and gas yield reached the optimum values of 20.01% and 51.96% at 800 ℃ with biochar-Ca catalyst particles,so the biochar-Ca catalyst could promote the formation of CH4 gas with high calorific value in pyrolysis gas,which could reach 12.69% under the optimum experimental conditions,and reduced the volume fraction of CO_2,the lowest value of CO_2 was 30.25%.Ca O could be used as a good acceptor of CO_2 to produce high calorific value fuel gas.By using the method of variance analysis,it was found that the P value of different kinds of catalyst was 4.9×10~(-6),which indicated that different kinds of catalysts had a very significant effect on the pyrolysis oil of corn straw particles.According to the analysis of liquid phase yield and gas yield,the order of activity of biochar-based catalysts for the catalytic reforming of corn straw pyrolysis volatiles was biochar-Ca > biochar-Fe > biochar > no catalyst.
引文
[1]骆仲泱,张晓东,周劲松,等.生物质热解焦油的热裂解与催化裂解[J].高校化学工程学报,2004,18(2):162-167.Luo Zhongyang,Zhang Xiaodong,Zhou Jinsong,et al.Experimental study on catalytic and thermal crac-king of tar from biomass pyrolysis[J].Journal of Chemical Engineering of Chinese Universities,2004,18(2):162-167.(in Chinese with English abstract)
[2]Asadullah M,Miyazawa T,Ito S I,et al.Novel bio-mass gasification method with high efficiency:Catalytic gasification at low temperature[J].Green Chemistry,2002,4(4):385-389.
[3]Alibeyli R,Karaduman A,Yeniova H,et al.Develop-ment of a poly functional catalyst for benzene product-ion from pyrolysis gasoline[J].Applied Catalysis A General,2003,238(2):279-287.
[4]边轶,刘石彩,简相坤.生物质热解焦油的性质与化学利用研究现状[J].生物质化学工程,2011,45(2):51-55.Bian Yi,Liu Shicai,Jian Xiangkun.The state art of view of research progress on characteristics and chemic-al utilization of tar from biomass pyrolysis[J].Bio-mass Chemical Engineering,2011,45(2):51-55.(in Chinese with English abstract)
[5]Dayton.Review of the literature on catalytic biomass tar destruction:milestone completion report[J].Journal of Physical Chemistry,2002,97(48):7437-7450.
[6]吴创之,周肇秋,阴秀丽,等.我国生物质能源发展现状与思考[J].农业机械学报,2009,40(1):91-99.Wu Chuangzhi,Zhou Zhaoqiu,Yin Xiuli,et al.Cur-rent status of biomass energy development in China[J].Transactions of the Chinese Society for Agricultural Machinery,2009,40(1):91-99.(in Chinese with English abstract)
[7]郭秀兰,黄鹤,周强,等.生物质焦油裂解催化剂研究进展[J].可再生能源,2004,15(1):9-13.Guo Xiulan,Huang He,Zhou Qiang,et al.The research status of catalysts for biomass tar cracking[J].Renew-able Energy Resources,2004,15(1):9-13.(in Chinese with English abstract)
[8]Simell P A,Bredenberg B S.Catalytic purification of tarry fuel gas[J].Fuel,1990,69(10):1219-1225.
[9]鲍卫仁,薛晓丽,曹青,等.MCM-41/SBA-15中孔分子筛对生物质热解油的催化裂解研究[J].燃料化学学报,2006,34(6):675-679.Bao Weiren,Xue Xiaoli,Cao Qing,et al.Study on bio-mass pyrolytic liquid products with MCM-41/SBA-15as catalyst[J].Journal of Fuel Chemistry and Technology,2006,34(6):675-679.(in Chinese with English abstract)
[10]Jesús Delgado,María P Aznar.Biomass Gasification with steam in fluidized bed:Effectiveness of CaO,MgO,and CaO-MgO for hot raw gas cleaning[J].Industrial&Engineering Chemistry Research,1997,36(5).DOI:10.1021/ie960273w.
[11]向玲,李立松,李新,等.炭基催化剂比表面积、孔径与硫容关系研究[J].四川环境,2014,33(1):18-21.Xiang Ling,Li Lisong,Li Xin,et al.Study on the relationship between specific surface area pore volume and sulfur capacity of activated carbon[J].Sichuan Environment,2014,33(1):18-21.(in Chinese with English abstract)
[12]尤占平,由世俊,李宪莉,等.生物质炭催化裂解焦油的性能研究[J].可再生能源,2011,29(3):39-42.You Zhanping,You Shijun,Li Xianli,et al.Study on biomass char on catalytic pyrolysis performance[J].Renewable Energy Resources,2011,29(3):39-42.(in Chinese with English abstract)
[13]Demirbas A.Combustion characteristics of different biomass fuels[J].Progress in Energy&Combustion Science,2004,30(2):219-230.
[14]张艳,解海卫,邓宇喆.生物质热失重特性及其机理初探[J].湖北农业科学,2015,54(11):2752-2754.Zhang Yan,Xie Haiwei,Deng Yuzhe,et al.Preliminary studies on the mechanism and characteristics of bio-mass pyrolysis[J].Hubei Agricultural Sciences,2015,54(11):2752-2754.(in Chinese with English abstract)
[15]王惺,李定凯,倪维斗,等.生物质压缩颗粒的燃烧特性[J].燃烧科学与技术,2007,13(1):86-90.Wang Xing,Li Dingkai,Ni Weidou et al.Combustion properties of pelletized biomass[J].Journal of Combustion Science and Technology,2007,13(1):86-90.(in Chinese with English abstract)
[16]Li C,Suzuki K.Kinetic analyses of biomass tar pyrolysis using the distributed activation energy model by TG/DTAtechnique[J].Journal of Thermal Analysis&Calorimetry,2009,98(1):261-266.
[17]Wang S,Dai G,Yang H,et al.Lignocellulosic biomass pyrolysis mechanism:A state-of-the-art review[J].Progress in Energy&Combustion Science,2017,62:33-86.
[18]Zhu T,Zhang S,Huang J,et al.Effect of calcium oxide on pyrolysis of coal in a fluidized bed[J].Fuel Processing Technology,2000,64(1/2/3):271-284.
[19]李永玲,吴占松.催化裂化条件对处理生物质热解焦油的影响[J].清华大学学报:自然科学版,2009,49(2):253-256.Li Yongling,Wu Zhansong.Effects of catalytic cracking conditions on biomass tar cracking conditions on biomass tar cracking[J].Journal Tsinghua University:Science and Technology,2009,49(2):253-256.(in Chinese with English abstract)
[20]项飞鹏,王智化,况敏,等.Fe2O3添加剂对宝日希勒褐煤热解特性的影响[J].中国电机工程学报,2016,36(1):172-178.Xiang Feipeng,Wang Zhihua,Kuang Min,et al.Effect of Fe2O3 additive on pyrolysis characteristics of Baorixile lignite[J].Proceedings of the CSEE,2016,36(1):172-178.(in Chinese with English abstract)
[21]Chareonpanich M,Zhanguo Z,Tomita A,et al.Effect of catalysts on yields of monocyclic aromatic hydrocarbons in hydro cracking of coal volatile matter[J].Fuel,1995,74(11):1636-1640.
[22]Yu J,Tian F J,Chow M C,et al.Effect of iron on the gasification of Victorian brown coal with steam:Enhancement of hydrogen production[J].Fuel,2006,85(2):127-133.
[23]王树荣,骆仲泱.生物质组分热裂解[M].北京:科学出版社,2013.
[24]潘春鹏,陈翀,黄群星,等.添加CaO对生物热解焦油生成的影响研究[J].热力发电,2012,41(8):24-29.Pang Chunpeng,Chen Chong,Huang Qunxing et al.Experimental study on influence of CaO addition on tar generation during biomass pyrolysis[J].Thermal Power Generation,2012,41(8):24-29.(in Chinese with English abstract)
[25]孟凡彬,孟军.玉米秸秆炭和木屑炭催化裂解焦油的试验研究[J].沈阳农业大学学报,2017,48(4):472-476.Meng Fanbin,Meng Jun.Experimental study on catalytic cracking of tar with corn stalk charcoal and sawdust charcoal[J].Journal of Shenyang Agricultural University,2017,48(4):472-476.(in Chinese with English abstract)
[26]林郁郁.CaO伴随生物质热裂解制油在线脱氧的实验研究[D].上海:上海交通大学,2011.Lin Yuyu.Experimental Investigation on Biomass Fast Pyrolysis in the Presence of CaO for Insitude Oxygenation of Bio-oil[D].Shanghai:Shanghai JiaoTong University,2011.(in Chinese with English abstract)
[27]谢威,郭瓦力,周世贤,等.生物质焦油在氧化钙上的催化裂解研究[J].沈阳化工大学学报,2000(3):205-208.Xie Wei,Guo Wali,Zhou Shixian,et al.Research of biomass tar on calcium oxide[J].Shenyang Institute of Chemical Technology,2000(3):205-208.(in Chinese with English abstract)
[28]Moulijn J A,Kapteijn F.Towards a unified theory of reactions of carbon with oxygen-containing molecules[J].Carbon,1995,33(8):1155-1165.
[29]Urasaki K,Tanimoto N,Hayashi T,et al.Hydrogen production via steam iron reaction using iron oxide modified with very small amounts of palladium and zirconia[J].Applied Catalysis A General,2005,288(1):143-148.
[30]Swierczynski D,Courson C,Kiennemann A.Study of steam reforming of toluene used as model compound of tar produced by biomass gasification[J].Chemical Engineering&Processing Process Intensification,2008,47(3):508-513.
[31]Li C,Suzuki K.Tar property,analysis,reforming mechanism and model for biomass gasification:An overview[J].Renewable&Sustainable Energy Reviews,2009,13(3):594-604
[32]李庆钊,林柏泉,赵长遂,等.基于傅里叶红外光谱的高温煤焦表面化学结构特性分析[J].中国电机工程学报,2011,31(32):46-52.Li Qingzhao,Lin Baiquan,Zhao Changsui,et al.Chemical structure analysis of coal char surface based on Fouriertransform infrared spectrometer[J].Proceedings of the CSEE,2011,31(32):46-52.(in Chinese with English abstract)
[33]庞赟佶,李腾飞,陈义胜,等.矿物质添加剂对玉米秸秆粉末催化热解特性的影响[J].农业工程学报,2018,34(14):221-226.Pang Yunji,Li Tengfei,Chen Yisheng,et al Effects of mineral additives on catalytic pyrolysis characteristics of corn stalk powder[J].Transactions of the Chinese Society of Agricultural Engineering(Transactions of the CSAE),2018,34(14):221-226.(in Chinese with English abstract)
[2]Asadullah M,Miyazawa T,Ito S I,et al.Novel bio-mass gasification method with high efficiency:Catalytic gasification at low temperature[J].Green Chemistry,2002,4(4):385-389.
[3]Alibeyli R,Karaduman A,Yeniova H,et al.Develop-ment of a poly functional catalyst for benzene product-ion from pyrolysis gasoline[J].Applied Catalysis A General,2003,238(2):279-287.
[4]边轶,刘石彩,简相坤.生物质热解焦油的性质与化学利用研究现状[J].生物质化学工程,2011,45(2):51-55.Bian Yi,Liu Shicai,Jian Xiangkun.The state art of view of research progress on characteristics and chemic-al utilization of tar from biomass pyrolysis[J].Bio-mass Chemical Engineering,2011,45(2):51-55.(in Chinese with English abstract)
[5]Dayton.Review of the literature on catalytic biomass tar destruction:milestone completion report[J].Journal of Physical Chemistry,2002,97(48):7437-7450.
[6]吴创之,周肇秋,阴秀丽,等.我国生物质能源发展现状与思考[J].农业机械学报,2009,40(1):91-99.Wu Chuangzhi,Zhou Zhaoqiu,Yin Xiuli,et al.Cur-rent status of biomass energy development in China[J].Transactions of the Chinese Society for Agricultural Machinery,2009,40(1):91-99.(in Chinese with English abstract)
[7]郭秀兰,黄鹤,周强,等.生物质焦油裂解催化剂研究进展[J].可再生能源,2004,15(1):9-13.Guo Xiulan,Huang He,Zhou Qiang,et al.The research status of catalysts for biomass tar cracking[J].Renew-able Energy Resources,2004,15(1):9-13.(in Chinese with English abstract)
[8]Simell P A,Bredenberg B S.Catalytic purification of tarry fuel gas[J].Fuel,1990,69(10):1219-1225.
[9]鲍卫仁,薛晓丽,曹青,等.MCM-41/SBA-15中孔分子筛对生物质热解油的催化裂解研究[J].燃料化学学报,2006,34(6):675-679.Bao Weiren,Xue Xiaoli,Cao Qing,et al.Study on bio-mass pyrolytic liquid products with MCM-41/SBA-15as catalyst[J].Journal of Fuel Chemistry and Technology,2006,34(6):675-679.(in Chinese with English abstract)
[10]Jesús Delgado,María P Aznar.Biomass Gasification with steam in fluidized bed:Effectiveness of CaO,MgO,and CaO-MgO for hot raw gas cleaning[J].Industrial&Engineering Chemistry Research,1997,36(5).DOI:10.1021/ie960273w.
[11]向玲,李立松,李新,等.炭基催化剂比表面积、孔径与硫容关系研究[J].四川环境,2014,33(1):18-21.Xiang Ling,Li Lisong,Li Xin,et al.Study on the relationship between specific surface area pore volume and sulfur capacity of activated carbon[J].Sichuan Environment,2014,33(1):18-21.(in Chinese with English abstract)
[12]尤占平,由世俊,李宪莉,等.生物质炭催化裂解焦油的性能研究[J].可再生能源,2011,29(3):39-42.You Zhanping,You Shijun,Li Xianli,et al.Study on biomass char on catalytic pyrolysis performance[J].Renewable Energy Resources,2011,29(3):39-42.(in Chinese with English abstract)
[13]Demirbas A.Combustion characteristics of different biomass fuels[J].Progress in Energy&Combustion Science,2004,30(2):219-230.
[14]张艳,解海卫,邓宇喆.生物质热失重特性及其机理初探[J].湖北农业科学,2015,54(11):2752-2754.Zhang Yan,Xie Haiwei,Deng Yuzhe,et al.Preliminary studies on the mechanism and characteristics of bio-mass pyrolysis[J].Hubei Agricultural Sciences,2015,54(11):2752-2754.(in Chinese with English abstract)
[15]王惺,李定凯,倪维斗,等.生物质压缩颗粒的燃烧特性[J].燃烧科学与技术,2007,13(1):86-90.Wang Xing,Li Dingkai,Ni Weidou et al.Combustion properties of pelletized biomass[J].Journal of Combustion Science and Technology,2007,13(1):86-90.(in Chinese with English abstract)
[16]Li C,Suzuki K.Kinetic analyses of biomass tar pyrolysis using the distributed activation energy model by TG/DTAtechnique[J].Journal of Thermal Analysis&Calorimetry,2009,98(1):261-266.
[17]Wang S,Dai G,Yang H,et al.Lignocellulosic biomass pyrolysis mechanism:A state-of-the-art review[J].Progress in Energy&Combustion Science,2017,62:33-86.
[18]Zhu T,Zhang S,Huang J,et al.Effect of calcium oxide on pyrolysis of coal in a fluidized bed[J].Fuel Processing Technology,2000,64(1/2/3):271-284.
[19]李永玲,吴占松.催化裂化条件对处理生物质热解焦油的影响[J].清华大学学报:自然科学版,2009,49(2):253-256.Li Yongling,Wu Zhansong.Effects of catalytic cracking conditions on biomass tar cracking conditions on biomass tar cracking[J].Journal Tsinghua University:Science and Technology,2009,49(2):253-256.(in Chinese with English abstract)
[20]项飞鹏,王智化,况敏,等.Fe2O3添加剂对宝日希勒褐煤热解特性的影响[J].中国电机工程学报,2016,36(1):172-178.Xiang Feipeng,Wang Zhihua,Kuang Min,et al.Effect of Fe2O3 additive on pyrolysis characteristics of Baorixile lignite[J].Proceedings of the CSEE,2016,36(1):172-178.(in Chinese with English abstract)
[21]Chareonpanich M,Zhanguo Z,Tomita A,et al.Effect of catalysts on yields of monocyclic aromatic hydrocarbons in hydro cracking of coal volatile matter[J].Fuel,1995,74(11):1636-1640.
[22]Yu J,Tian F J,Chow M C,et al.Effect of iron on the gasification of Victorian brown coal with steam:Enhancement of hydrogen production[J].Fuel,2006,85(2):127-133.
[23]王树荣,骆仲泱.生物质组分热裂解[M].北京:科学出版社,2013.
[24]潘春鹏,陈翀,黄群星,等.添加CaO对生物热解焦油生成的影响研究[J].热力发电,2012,41(8):24-29.Pang Chunpeng,Chen Chong,Huang Qunxing et al.Experimental study on influence of CaO addition on tar generation during biomass pyrolysis[J].Thermal Power Generation,2012,41(8):24-29.(in Chinese with English abstract)
[25]孟凡彬,孟军.玉米秸秆炭和木屑炭催化裂解焦油的试验研究[J].沈阳农业大学学报,2017,48(4):472-476.Meng Fanbin,Meng Jun.Experimental study on catalytic cracking of tar with corn stalk charcoal and sawdust charcoal[J].Journal of Shenyang Agricultural University,2017,48(4):472-476.(in Chinese with English abstract)
[26]林郁郁.CaO伴随生物质热裂解制油在线脱氧的实验研究[D].上海:上海交通大学,2011.Lin Yuyu.Experimental Investigation on Biomass Fast Pyrolysis in the Presence of CaO for Insitude Oxygenation of Bio-oil[D].Shanghai:Shanghai JiaoTong University,2011.(in Chinese with English abstract)
[27]谢威,郭瓦力,周世贤,等.生物质焦油在氧化钙上的催化裂解研究[J].沈阳化工大学学报,2000(3):205-208.Xie Wei,Guo Wali,Zhou Shixian,et al.Research of biomass tar on calcium oxide[J].Shenyang Institute of Chemical Technology,2000(3):205-208.(in Chinese with English abstract)
[28]Moulijn J A,Kapteijn F.Towards a unified theory of reactions of carbon with oxygen-containing molecules[J].Carbon,1995,33(8):1155-1165.
[29]Urasaki K,Tanimoto N,Hayashi T,et al.Hydrogen production via steam iron reaction using iron oxide modified with very small amounts of palladium and zirconia[J].Applied Catalysis A General,2005,288(1):143-148.
[30]Swierczynski D,Courson C,Kiennemann A.Study of steam reforming of toluene used as model compound of tar produced by biomass gasification[J].Chemical Engineering&Processing Process Intensification,2008,47(3):508-513.
[31]Li C,Suzuki K.Tar property,analysis,reforming mechanism and model for biomass gasification:An overview[J].Renewable&Sustainable Energy Reviews,2009,13(3):594-604
[32]李庆钊,林柏泉,赵长遂,等.基于傅里叶红外光谱的高温煤焦表面化学结构特性分析[J].中国电机工程学报,2011,31(32):46-52.Li Qingzhao,Lin Baiquan,Zhao Changsui,et al.Chemical structure analysis of coal char surface based on Fouriertransform infrared spectrometer[J].Proceedings of the CSEE,2011,31(32):46-52.(in Chinese with English abstract)
[33]庞赟佶,李腾飞,陈义胜,等.矿物质添加剂对玉米秸秆粉末催化热解特性的影响[J].农业工程学报,2018,34(14):221-226.Pang Yunji,Li Tengfei,Chen Yisheng,et al Effects of mineral additives on catalytic pyrolysis characteristics of corn stalk powder[J].Transactions of the Chinese Society of Agricultural Engineering(Transactions of the CSAE),2018,34(14):221-226.(in Chinese with English abstract)