Gasification characteristics of coal in decoupled triple bed

doi:10.11949/0438-1157.20190312

Abstract

Abstract:

Catalytic steam gasification of coal was carried out in a pyrolysis, reforming and combustion separated decoupled triple bed gasification system. The olivine was used as the in-situ tar cracking catalytic bed material, and the coal catalytic gasification experiment was carried out. The effects of coal types, coal feeding rate, reformer temperature and steam to carbon mass ratio (S/C) on gasification performance were investigated. The results showed that the gas yield, carbon conversion, cold gas efficiency and H₂ content in the gas increased with the increasing volatile content of coal. The carbon conversion and cold gas efficiency is relatively low due to the char is not involved in gasification reaction. The gas yield and gas composition influenced by coal to catalyst ratio. The gas yield increased from 0.28 m³/kg to 0.46 m³/kg and the H₂ content increased from 28.4% to 50.5% with increasing coal feeding rate from 0.12 kg/h to 0.30 kg/h. Increasing reforming temperature and S/C were beneficial to promote the tar cracking and conversion, and thus increased the gas yield. A gas yield of 0.6 m³/kg tar content as low as 2.11 g/m³ has been achieved at the reformer temperature was 850℃ and S/C of 1.0. The addition of steam enhanced the steam reforming reaction of tar, and increased the gas yield. However the excessive steamcause shorter residence time of tar in reformer that results reduction degree of tar steam reforming reaction.

Key words: coal gasification, decoupled triple bed, solid heat carrier, olivine

摘要：

采用热解、重整、燃烧解耦分离的解耦三床气化（decoupled triple bed gasification，DTBG）系统，以橄榄石为原位焦油裂解催化床料，进行了煤催化气化实验。研究了煤种、煤进料速率、重整器温度以及水碳比（S/C）对煤热解焦油裂解/重整反应的影响。结果显示：随着煤挥发分含量增加，气体产率、碳转化率、冷煤气效率以及产气中的H₂含量增加。由于半焦不参与气化反应，导致碳转化率和冷煤气效率偏低。煤和催化剂比例的改变会影响气体产率和产气组成，当煤的进料速率从0.12 kg/h增加到0.30 kg/h时，气体产率从0.28 m³/kg增加到0.46 m³/kg，H₂含量从28.4%增加到50.5%。重整器温度的升高有利于促进煤焦油裂解转化，从而增加气体产率。当重整器温度为850℃、S/C为1.0时，气体产率达到了0.60 m³/kg, 橄榄石催化剂有效地降低了焦油含量，焦油产率仅为2.11g/m³。S/C的升高增强了焦油水蒸气重整反应，但引入过量的水蒸气会导致反应器内气体的流速加快，缩短了反应物的停留时间和反应时长，减缓了焦油水蒸气重整反应的反应程度。

关键词: 煤气化, 解耦三床, 固体热载体, 橄榄石

CLC Number:

TQ 546.2

Tursun YALKUNJAN, Abduhani HAIRAT, Yue PAN, Abulizi ABULIKEMU, Talifu DILINUER, Fengyun MA, Shaoping XU. Gasification characteristics of coal in decoupled triple bed[J]. CIESC Journal, 2019, 70(8): 3040-3049.

亚力昆江·吐尔逊null, 艾热提·阿不都艾尼null, 潘岳, 阿布力克木·阿布力孜null, 迪丽努尔·塔力甫null, 马凤云, 徐绍平. 热解-重整-燃烧解耦的煤气化特性[J]. 化工学报, 2019, 70(8): 3040-3049.

Figures/Tables 9

References 33

1	王亚雄, 杨景轩, 张忠林, 等. 低阶煤热解-气化-燃烧TBCFB系统模拟及优化[J]. 化工学报, 2018, 69(8): 3596-3604.
	WangY X, YangJ X, ZhangZ L, et al. TBCFB system simulation and optimization for pyrolysis-gasification-combustion of low rank coal [J]. CIESC Journal, 2018, 69(8): 3596-3604.
2	ZhangJ, WangY, DongL, et al. Decoupling gasification: approach principle and technology justification [J]. Energy Fuels, 2010, 24(12): 6223-6232.
3	KoppatzS, PfeiferC, RauchR, et al. H₂ rich product gas by steam gasification of biomass with in situ CO₂ absorption in a dual fluidized bed system of 100MW fuel input[J]. Fuel Processing Technology, 2009, 90(7/8): 914-921.
4	RehlingB, HofbauerH, RauchR, et al. BioSNG—process simulation and comparison with first results from a 1-MW demonstration plant[J]. Biomass Conversion and Biorefinery, 2011, 1(2): 111-119.
5	GuanG, FushimiC, TsutsumiA. Prediction of flow behavior of the riser in a novel high solids flux circulating fluidized bed for steam gasification of coal or biomass[J]. Chemical Engineering Journal, 2010, 164(1): 221-229.
6	GuanG, FushimiC, TsutsumiA, et al. High-density circulating fluidized bed gasifier for advanced IGCC/IGFC—advantages and challenges [J]. Particuology, 2010, 8(6): 602-606.
7	XuG, MurakamiT, SudaT, et al. Two-stage dual fluidized bed gasification: its conception and application to biomass[J]. Fuel Processing Technology, 2009, 90(1): 137-144.
8	ZengX, ShaoR, WangF, et al. Industrial demonstration plant for the gasification of herb residue by fluidized bed two-stage process[J]. Bioresource Technology, 2016, 206: 93-98.
9	HenriksenU, AhrenfeldtJ, JensenT K, et al. The design, construction and operation of a 75 kW two-stage gasifier[J]. Energy, 2006, 31(10/11): 1542-1553.
10	张志远, 陈鸿伟, 赵争辉, 等. 钠盐对准东煤CO₂吸附能力及气化特性的影响 [J]. 化工学报, 2017, 68(4): 1629-1636.
	ZhangZ Y, ChenH W, ZhaoZ H, et al. Effect of sodium salts on CO₂ adsorption capacity and gasification of Zhundong coal [J]. CIESC Journal, 2017, 68(4): 1629-1636.
11	MarinkovicJ, ThunmanH, KnutssonP, et al. Characteristics of olivine as a bed material in an indirect biomass gasifier[J]. Chemical Engineering Journal, 2015, 279: 555-566.
12	ChristodoulouC, GrimekisD, PanopoulosK D, et al. Comparing calcined and un-treated olivine as bed materials for tar reduction in fluidized bed gasification [J]. Fuel Processing Technology, 2014, 124(5): 275-285.
13	李兰兰, 郑安庆, 冯宜鹏, 等. 橄榄石对甲苯催化重整反应的影响[J]. 燃料化学学报, 2015, 43(7): 806-815.
	LiL L, ZhengA Q, FengY P, et al. Effects of olivine on catalytic reforming of toluene[J]. Journal of Fuel Chemistry and Technology, 2015, 43(7): 806-815.
14	岳宝华, 卜宪昵, 汪学广, 等. 焙烧温度对橄榄石催化甲苯裂解性能的影响[J]. 化工学报, 2009, 60(2): 378-383.
	YueB H, BuX N, WangX G, et al. Effect of calcination temperature on catalytic performance of olivine for toluene cracking[J]. CIESC Journal, 2009, 60(2): 378-383.
15	ArandaG, DriftA V D, VreugdenhilB J, et al. Comparing direct and indirect fluidized bed gasification: effect of redox cycle on olivine activity (pages 711—720)[J]. Environmental Progress & Sustainable Energy, 2014, 33(3): 711-720.
16	FredrikssonH O A, LanceeR J, ThüneP C, et al. Olivine as tar removal catalyst in biomass gasification: catalyst dynamics under model conditions[J]. Applied Catalysis B: Environmental, 2013, 130/131(complete): 168-177.
17	ŚwierczyńskiD, CoursonC, BedelL, et al. Oxidation reduction behavior of iron-bearing olivines (Fe_xMg_1-_x)₂SiO₄ used as catalysts for biomass gasification [J]. Chem. Mater., 2006, 18(4): 897-905.
18	DeviL, PtasinskiK J, JanssenF J. Pretreated olivine as tar removal catalyst for biomass gasifiers: investigation using naphthalene as model biomass tar [J]. Fuel Processing Technology, 2005, 86(6): 707-730.
19	DeviL, PtasinskiK J, JanssenF J. Decomposition of naphthalene as a biomass tar over pretreated olivine: effect of gas composition, kinetic approach, and reaction scheme [J]. Industrial & Engineering Chemistry Research, 2005, 44(24): 9096-9104.
20	杨小芹, 徐绍平, 胡冠, 等. 不同矿源橄榄石对催化苯水蒸气重整的影响 [J]. 催化学报, 2009, 30(6): 497-502.
	YangX Q, XuS P, HuG, et al. Effects of olivines from different quarries on the steam reforming of benzene[J]. Chinese Journal of Catalysis, 2009, 30(6): 497-502.
21	StefanK, PfeiferC, HofbauerH. Comparison of the performance behaviour of silica sand and olivine in a dual fluidised bed reactor system for steam gasification of biomass at pilot plant scale[J]. Chemical Engineering Journal, 2011, 175(22): 468-483.
22	宋洋博, 徐绍平, 李伶俐, 等. Cu-橄榄石载氧体煤焦化学链气化实验研究[J]. 燃料化学学报, 2017, 45(8): 916-923.
	SongY B, XuS P, LiL L, alet . Chemical looping gasification of coal char with Cu-olivine oxygen carriers[J]. Journal of Fuel Chemistry and Technology, 2017, 45(8): 916-923.
23	邓靖, 李文英, 李晓红, 等. 橄榄石基固体热载体影响褐煤热解产物分布的分析[J]. 燃料化学学报, 2013, 41: 937-942.
	DengJ, LiW Y, LiX H, et al. Product distribution of lignite pyrolysis with olivine-based solid heat carrier[J]. Journal of Fuel Chemistry and Technology, 2013, 41: 937-942.
24	亚力昆江·吐尔逊, 潘岳, 别尔德汗·瓦提汗, 等. 基于热解-重整-燃烧解耦三床气化系统的生物质催化制富氢气体[J]. 农业工程学报, 2018, (1): 222-228.
	YalkunjanT, PanY, BieerdehanW, et al. Catalytic biomass gasification for hydrogen rich gas production in decoupled-triple-bed gasification system[J]. Transactions of the Chinese Society of Agricultural Engineering, 2018, (1): 222-228.
25	TursunY, XuS, AbulikemuA, et al. Biomass gasification for hydrogen rich gas in a decoupled triple bed gasifier with olivine and NiO/olivine [J]. Bioresour. Technol., 2019, 272: 241-248.
26	TursunY, XuS, WangG, et al. Tar formation during co-gasification of biomass and coal under different gasification condition[J]. Journal of Analytical and Applied Pyrolysis, 2015, 111: 191-199.
27	XiaoY, XuS, TursunY, et al. Catalytic steam gasification of lignite for hydrogen-rich gas production in a decoupled triple bed reaction system [J]. Fuel, 2017, 189: 57-65.
28	魏立纲, 徐绍平, 刘长厚, 等. 预煅烧对橄榄石生物质气化催化性能的影响[J]. 燃料化学学报, 2008, 36: 426-430.
	WeiL G, XuS P, LiuC H, et al. Effects of precalcination on catalytic activity of olivine in biomass gasification[J]. Journal of Fuel Chemistry and Technology, 2008, 36: 426-430.
29	崔银萍. 西部弱还原性煤在N₂气氛中的热转化特性研究[D]. 太原: 太原理工大学, 2007.
	CuiY P. The study on conversion character during pyrolysis of Chinese Western coals[D]. Taiyuan: Taiyuan University of Technology, 2007.
30	张志丰, 王亦飞, 朱龙雏, 等. 基于铁基载氧体的无烟煤化学链燃烧过程中硫分布特性[J]. 化工学报, 2018, 69(4): 1578-1585
	ZhangZ F, WangY F, ZhuL C, et al. Distribution of sulfur in chemical looping combustion of anthracite based on Fe-based oxygen carrier[J]. CIESC Journal, 2018, 69(4): 1578-1585.
31	田斌, 杨芳芳, 庞亚恒, 等. 气化温度对型煤加压固定床气化反应特性的影响[J]. 中国电机工程学报, 2013, 33(z1): 128-134.
	TianB, YangF F, PangY H, et al. Effect of temperature on the reactivity characteristics of briquette during high pressure fixed-bed gasification[J]. Proceedings of the CSEE, 2013, 33(z1): 128-134.
32	乌晓江, 张忠孝, 朴桂林, 等. 煤粉加压气流床气化特性实验研究[J]. 工程热物理学报, 2008, 29(8): 1431-1434.
	WuX J, ZhangZ X, PuG L, et al. Experimental study on gasification characteristics of coal in lab-scale down flow gasifier[J]. Journal of Engineering Thermophysics, 2008, 29(8): 1431-1434.
33	王勤辉, 揭涛, 李小敏, 等. 反应气氛对不同煤灰烧结温度影响的研究[J]. 燃料化学学报, 2010, 38(1): 17-22.
	WangQ H, JieT, LiX M, et al. Experiments of the effects of reaction atmosphere on the coal ash sintering temperature[J]. Journal of Fuel Chemistry and Technology, 2010, 38(1): 17-22.

原料	工业分析(ad)/%(mass)				元素分析(daf)/%(mass)
原料	水分	灰分	挥发分	固定碳	C	H	O	N	S
WCW	6.96	19.13	30.56	43.35	73.77	3.65	19.64	0.82	2.12
NMG	10.47	3.66	28.88	56.99	76.97	4.09	17.64	0.70	0.60
HEM	1.82	5.71	41.29	51.18	75.60	5.03	18.05	0.90	0.42

原料	工业分析(ad)/%(mass)				元素分析(daf)/%(mass)
原料	水分	灰分	挥发分	固定碳	C	H	O	N	S
WCW	6.96	19.13	30.56	43.35	73.77	3.65	19.64	0.82	2.12
NMG	10.47	3.66	28.88	56.99	76.97	4.09	17.64	0.70	0.60
HEM	1.82	5.71	41.29	51.18	75.60	5.03	18.05	0.90	0.42

Parameter	Value
total bed material inventory /kg	5.0
circulating rate of bed material /(kg/h)	4.5
coal feeding rate/ (kg/h)	0.12－0.30
bed materials particle size /mm	0.45－0.90
coal particle size /mm	0.45－0.90
residence time of solid in reformer/min	30
residence time of solid in pyrolyzer /min	7
bed height in the pyrolyzer /mm	200
reformer temperature /℃	750－850
pyrolyzer temperature /℃	700
combustor temperature /℃	850
air flow rate of combustor/ (m³/h)	4.2－4.6
operation pressure/MPa	0.1

Parameter	Value
total bed material inventory /kg	5.0
circulating rate of bed material /(kg/h)	4.5
coal feeding rate/ (kg/h)	0.12－0.30
bed materials particle size /mm	0.45－0.90
coal particle size /mm	0.45－0.90
residence time of solid in reformer/min	30
residence time of solid in pyrolyzer /min	7
bed height in the pyrolyzer /mm	200
reformer temperature /℃	750－850
pyrolyzer temperature /℃	700
combustor temperature /℃	850
air flow rate of combustor/ (m³/h)	4.2－4.6
operation pressure/MPa	0.1

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