甲烷活化与煤热解耦合过程提高焦油产率研究进展

doi:10.11949/j.issn.0438-1157.20170465

摘要/Abstract

摘要：

热解是实现煤清洁高效利用的重要途径之一。针对传统煤热解焦油收率低的现状，从煤热解反应机理出发，围绕甲烷催化/等离子体活化与煤热解过程耦合提高焦油收率的研究工作进行综述，重点介绍了甲烷部分氧化、甲烷二氧化碳重整、甲烷芳构化、甲烷水蒸气重整及甲烷等离子体活化与煤热解耦合过程特点以及对焦油产率的影响。结果显示，相对氮气和氢气气氛下热解，耦合过程焦油产率显著提高，并具有煤种普适性。同时借助同位素示踪技术对耦合过程焦油产率提高机理进行分析。结果表明，甲烷经催化/等离子体活化后产生的活性物质通过与煤热解形成的自由基结合，参与了焦油的形成，是焦油产率显著提高的根本原因。耦合反应器的设计和甲烷活化催化剂的开发是今后该过程工业应用的关键。

关键词: 热解, 甲烷, 活化, 焦油, 等离子体, 自由基

Abstract:

Pyrolysis is an efficient approach for coal clean utilization.To improve the tar yield in coal pyrolysis,several processes to integrate catalytic and/or low-temperature plasma activation of methane (including partial oxidation,CO₂ reforming,steam reforming,methane aromatization and cold plasmas) with coal pyrolysis were reviewed.The results showed that all integrated processes can obviously improve the tar yield compared with the pyrolysis under N₂ or H₂,and are adaptable to different coals.These methods provide new approaches for enhancing the tar yield.The mechanism for high tar yield was analyzed by the isotopic trace techniques.The analysis of main components in the tar from the integrated process by GC-MS indicates that some free radicals (like· CH_x,·H) are formed by the catalytic activation of methane on Ni-based catalysts or the excitation by electrons with higher energy in low-temperature plasma.These active species participate in the formation of coal tar by the interaction with the free radicals cracked from coal,leading to the remarkable enhancement.The reactor designing of the integrated process and the catalyst development with good catalytic performances for methane activation are the key to the industrial utilization in the future.

Key words: pyrolysis, methane, activation, tar, plasma, free radicals

中图分类号:

TQ546

靳立军, 李扬, 胡浩权. 甲烷活化与煤热解耦合过程提高焦油产率研究进展[J]. 化工学报, 2017, 68(10): 3669-3677.

JIN Lijun, LI Yang, HU Haoquan. Research progress of integrated methane activation with coal pyrolysis for improving coal tar yield[J]. CIESC Journal, 2017, 68(10): 3669-3677.

参考文献 35

[1]	徐全清, 卢雁, 张香平, 等. 煤热解与制备高价值化学品的研究现状与趋势[J]. 河南师范大学学报(自然科学版), 2006, 34(3):78-82. XU Q Q, LU Y, ZHANG X P, et al. Status and progress of coal pyrolysis and conversion to valuable chemicals[J]. Journal of Henan Normal University (Natural Science), 2006, 34(3):78-82.
[2]	TROMP P J J. Coal pyrolysis[D]. Amsterdam:University of Amsterdam, 1987.
[3]	刘振宇. 煤化学的前沿与挑战:结构与反应[J]. 中国科学:化学, 2014, 44(9):1431-1438. LIU Z Y. Advancement in coal chemistry:structure and reactivity[J]. Scientia Sinica Chimica, 2014, 44(9):1431-1438.
[4]	GRAFF R A, BRANDES S D. Modification of coal by subcritical steam:pyrolysis and
[5]	MIURA K. Mild conversion of coal for producing valuable chemicals[J]. Fuel Process Technol., 2000, 62:119-135.
[6]	ZHOU Q, HU H Q, LIU Q R, et al. Effect of hydrogen pretreatment on sulfur removal during coal hydropyrolysis[C]//Proceedings, Twenty-First Annual International Pittsburgh Coal Conference. Osaka, Japan, 2004:13-17.
[7]	CYPRES R, LI B Q. Effects of pretreatment by various gases on hydropyrolysis of a Belgian coal[J]. Fuel Process. Technol., 1988, 20:337-347.
[8]	陈兆辉, 敦启孟, 石勇, 等. 热解温度和反应气氛对输送床煤快速热解的影响[J]. 化工学报, 2017, 68(4):1566-1573. CHEN Z H, DUN Q M, SHI Y, et al. Effects of pyrolysis temperature and atmosphere on rapid coal pyrolysis in a transport bed reactor[J]. CIESC Journal, 2017, 68(4):1566-1573.
[9]	廖洪强, 孙成功, 李保庆. 煤-焦炉气共热解特性的研究[J]. 燃料化学学报, 1997, 25(2):104-108. LIAO H Q, SUN C G, LI B Q. Coal pyrolysis with hydrogen-rich gases[J]. Journal of Fuel Chemistry and Technology, 1997, 25(2):104-108.
[10]	LEI Z P, ZHANG K, HU Z Q, et al. Effect of ionic liquid 1-butyl-3-methyl-imidazolium dihydrogen phosphate pretreatment on pyrolysis of Shengli lignite[J], Fuel Processing Technology, 2016, 147:26-31.
[11]	董鹏伟, 岳君容, 高士秋, 等. 热预处理影响褐煤热解行为研究[J]. 燃料化学学报, 2012, 40(8):897-905. DONG P W, YUE J R, GAO S Q, et al. Influence of thermal pretreatment on pyrolysis of lignite[J]. Journal of Fuel Chemistry and Technology, 2012, 40(8):897-905.
[12]	王志青, 白宗庆, 李文, 等. 吡啶预处理抑制煤热解过程中交联反应的研究[J]. 燃料化学学报, 2008, 36(6):641-645. WANG Z Q, BAI Z Q, LI W, et al. Suppressing cross-linking reactions during pyrolysis of lignite pretreated by pyridine[J]. Journal of Fuel Chemistry and Technology, 2008, 36(6):641-645.
[13]	MIURA K. Flash pyrolysis of coal in solvent for controlling product distribution during pyrolysis of lignite pretreated by pyridine[J]. Energy & Fuels, 1992, 6:179-184.
[14]	NAITO S, TAKADA A, TOKIZAWA S, et al. Mechanistic study on the methane activation over various supported molybdenum carbide catalysts with isotopic tracer methods[J]. Appl. Catal. A:General, 2005, 289:22-27.
[15]	WEI J, IGLESIA E. Isotopic and kinetic assessment of the mechanism of reactions of CH4 with CO2 or H2O to form synthesis gas and carbon on nickel catalysts[J]. Journal of Catalysis, 2004, 224:370-383.
[16]	贺黎明, 沈召军. 甲烷的转化和利用[M]. 北京:化学工业出版社, 2005. HE L M, SHEN Z J. Conversion and Utilization of Methane[M]. Beijing:Chemical Industry Press, 2015.
[17]	LIU Q R, HU H Q, ZHU S W. Integrated process of coal pyrolysis with catalytic partial oxidation of methane[C]//2005 International Conference on Coal Science and Technology. Okinawa, Japan, 2005.
[18]	刘全润. 煤的热解转化和脱硫研究[D]. 大连:大连理工大学, 2006. LIU Q R. Coal conversion and desulfurization during pyrolysis[D]. Dalian:Dalian University of Technology, 2006.
[19]	LIU J H, HU H Q, JIN L J, et al. Effects of catalysts and reaction conditions on the integrated process of coal pyrolysis with CO2 reforming of methane[J]. Energy Fuels, 2009, 23:4782-4786.
[20]	ATTAR A. Chemistry thermodynamics and kinetics of reactions of sulfur in coal-gas reactions:a review[J]. Fuel, 1978, 57(2):201-212.
[21]	LIU J H, HU H Q, JIN L J, et al. Integrated coal pyrolysis with CO2 reforming of methane over Ni/MgO catalysts for improving tar yield[J]. Fuel Processing Technology, 2010, 91:419-423.
[22]	刘佳禾. 煤热解与甲烷二氧化碳重整耦合制油过程研究[D]. 大连:大连理工大学, 2012. LIU J H. Integrated process of coal pyrolysis with CO2 reforming of methane for tar production[D]. Dalian:Dalian University of Technology, 2012.
[23]	周逊. 甲烷芳构化与煤热解耦合提高焦油产率研究[D]. 大连:大连理工大学, 2011. ZHOU X. Integrated process of coal pyrolysis with methane aromatization for improving tar yield[D]. Dalian:Dalian University of Technology, 2011.
[24]	JIN L J, ZHOU X, HE X F, et al. Integrated coal pyrolysis with methane aromatization over Mo/HZSM-5 for improving tar yield[J]. Fuel, 2013, 114:187-190.
[25]	DONG C, JIN L J, LI Y, et al. Integrated process of coal pyrolysis with steam reforming of methane for improving the tar yield[J]. Energy & Fuels, 2014, 28:7377-7384.
[26]	董婵. 煤热解与甲烷催化重整耦合过程研究[D]. 大连:大连理工大学, 2016. DONG C. Integrated process of coal pyrolysis with catalytic reforming of methane[D]. Dalian:Dalian University of Technology, 2016.
[27]	DONG C, JIN L J, LI Y, et al. Mechanism of integrated process of coal pyrolysis with SRM by isotopic tracer method[C]//13th China-Japan Symposium on Coal and C1 Chemistry. Dunhuang, Gansu, China, 2015.
[28]	RUEANGJITT N, SREETHAWONG T, CHAVADEJ S. Reforming of CO2-containing natural gas using an AC gliding arc system:effects of operational parameters and oxygen addition in fed[J]. Plasma Chem. Plasma Process., 2008, 28:49-67.
[29]	BROMBERGA L, COHNA D R, RABINOVICH A, et al. Plasma catalytic reforming of methane[J]. International Journal of Hydrogen Energy, 1999, 24:1131-1137.
[30]	贺新福. 甲烷低温等离子体活化与煤热解耦合过程研究[D]. 大连:大连理工大学, 2012. HE X F. Integrated process of coal pyrolysis with methane activation by cold plasma[D]. Dalian:Dalian University of Technology, 2012.
[31]	HE X F, JIN L J, WANG D, et al. Integrated process of coal pyrolysis with CO2 reforming of methane by dielectric barrier discharge plasma[J]. Energy Fuels, 2011, 25:4036-4042.
[32]	冯勇强. 火花放电等离子体活化CH4-CO2重整与煤热解耦合过程研究[D]. 大连:大连理工大学, 2016. FENG Y Q. Integrated process of coal pyrolysis with CO2 reforming of methane by spark-discharge plasma[D]. Dalian:Dalian University of Technology, 2016.
[33]	JIN L J, LI Y, FENG Y Q, et al. Integrated process of coal pyrolysis with CO2 reforming of methane by spark discharge plasma[J]. Journal of Analytic and Applied Pyrolysis, 2017, 126:194-200.
[34]	WANG P F, JIN L J, LIU J H, et al. Isotope analysis for understanding the tar formation in the integrated process of coal pyrolysis with CO2 reforming of methane[J]. Energy Fuels, 2010, 24:4402-4407.
[35]	WANG P F, JIN L J, LIU J H, et al. Analysis of coal tar derived from pyrolysis at different atmospheres[J]. Fuel, 2013, 104:14-21.