Aspen Plus modeling of the entrained bed coal gasification: equilibrium model and kinetic model

doi:10.16085/j.issn.1000-6613.2020-1764

Abstract

Abstract:

The equilibrium model and kinetic model of GE gasifier were established based on Aspen Plus, and the gas composition and carbon conversion were calculated. The model is divided into three stages: pyrolysis, gasification and gas-liquid separation. Among them, the gasification stage is divided into preliminary gasification and gasification reforming, so as to obtain the distribution of gasification products at a constant temperature. The Gibbs reactor RGIBBS is used in the gasification stage of the equilibrium model, and the gasification products in the system are calculated based on the Gibbs free energy minimization principle. The perfect mixing flow reactor RCSTR is used in the gasification stage of the kinetic model, and the gasification products in the system are calculated based on the kinetic mechanism of the coal gasification reaction. The model results are compared with the actual engineering data of GE gasifier, and the results show that the equilibrium model can reflect the change trend of gasification results to some extent, but the accuracy of the prediction results is not enough, while the kinetic model based on gasification reaction mechanism can well predict the gasification results of GE gasifier. The reaction time is set for the perfect mixing flow reactor in the kinetic model, which can provide some guidance for the production of GE gasifier. The results show that a good gasification effect can be achieved when the reaction residence time is 3.5s. Temperature is an important factor affecting the gasification reaction rate and product distribution. The influence of gasification temperature on gas composition and carbon conversion is simulated by the kinetic model of coal gasification. The results show that with the increase of gasification temperature, the CO content increases, the H₂ content is basically the same, the CO₂ content decreases, and the carbon conversion increases.

Key words: Aspen Plus, GE gasifier, equilibrium model, kinetic model, reaction residence time, temperature

摘要：

基于Aspen Plus软件建立了GE气流床煤气化的平衡模型和动力学模型，计算了气化的煤气组成和碳转化率。模型分为热解、气化和气液分离三个阶段。其中，气化阶段又分为初步气化和气化重整，从而获得气化产物在恒定温度下的分布。平衡模型的气化阶段使用了吉布斯反应器RGIBBS，基于吉布斯自由能最小化原理对体系内的气化产物进行计算；动力学模型的气化阶段使用了全混流反应器RCSTR，基于煤气化反应的动力学机理对体系内的气化产物进行计算。模拟值与GE气化炉的实际工程数据进行了对比，结果表明，平衡模型可在一定程度上反映气化结果的变化趋势，但预测结果的准确性有所欠缺，而基于气化反应机理建立的动力学模型能很好地预测GE气化炉的气化结果。对动力学模型中的全混流反应器进行反应时间设定，可以对GE气化炉生产提供一定的指导，结果表明：反应停留时间为3.5s时就可以达到很好的气化效果。温度是影响气化反应速率及产物分布的重要因素，利用煤气化的动力学模型模拟了气化温度对气体组成及碳转化率的影响，结果表明：随着气化温度的升高，CO含量逐渐增加，H₂含量基本不变，CO₂含量逐渐减小，碳转化率逐渐升高。

关键词: Aspen Plus, GE气化炉, 平衡模型, 动力学模型, 反应停留时间, 温度

CLC Number:

TQ546

ZHENG Zhihang, ZHANG Jiayuan, LI Qian, ZHOU Haoyu. Aspen Plus modeling of the entrained bed coal gasification: equilibrium model and kinetic model[J]. Chemical Industry and Engineering Progress, 2021, 40(8): 4165-4172.

郑志行, 张家元, 李谦, 周浩宇. 气流床煤气化的Aspen Plus建模：平衡模型和动力学模型[J]. 化工进展, 2021, 40(8): 4165-4172.

Figures/Tables 14

反应类型	反应式	反应数
气固反应
碳燃烧反应	C+（λ+2）/（2λ+2）O₂ $→$ λ/（1+λ）CO+1/（1+λ）CO₂	R1
水蒸气转化反应	C+H₂O $→$ CO+H₂	R2
歧化反应	C+CO₂ $→$ 2CO	R3
甲烷化反应	C+H₂ $→$ CH₄	R4
气相反应
氢气燃烧反应	H₂+（1/2）O₂ $→$ H₂O	R5
水煤气变换反应	CO+H₂O $→$ CO₂+H₂	R6
甲烷燃烧反应	CH₄+2O₂ $→$ CO₂+2H₂O	R7

反应类型	反应式	反应数
气固反应
碳燃烧反应	C+（λ+2）/（2λ+2）O₂ $→$ λ/（1+λ）CO+1/（1+λ）CO₂	R1
水蒸气转化反应	C+H₂O $→$ CO+H₂	R2
歧化反应	C+CO₂ $→$ 2CO	R3
甲烷化反应	C+H₂ $→$ CH₄	R4
气相反应
氢气燃烧反应	H₂+（1/2）O₂ $→$ H₂O	R5
水煤气变换反应	CO+H₂O $→$ CO₂+H₂	R6
甲烷燃烧反应	CH₄+2O₂ $→$ CO₂+2H₂O	R7

气相反应	k_i	E_i
氢气燃烧反应	8.83×10⁸	9.976×10⁴
水煤气变换反应	2.978×10¹²	3.69×10⁵
甲烷燃烧反应	3.552×10¹⁴	9.304×10⁶

序号	煤种	元素分析（干燥基）/%							煤粉进料速率/g·s^-1	H₂O/煤粉 /g·g^-1	O₂/煤粉 /g·g^-1	入炉温度/K
序号	煤种	C	H	N	S	Cl	O	灰分	煤粉进料速率/g·s^-1	H₂O/煤粉 /g·g^-1	O₂/煤粉 /g·g^-1	煤	H₂O	O₂
1	Illinois No.6	74.05	6.25	0.71	1.77	0.37	1.32	15.53	76.66	0.24	0.87	505	697	298
2	Wyodak	78.37	5.79	0.92	0.07	0.08	3.7	11.05	86	0.32	0.9	414	672	298
3	SRC-Ⅱ	64.9	3.65	1.25	2.96	—	1.7	25.54	126.11	0.3	0.7	505	697	298
4	Exxon DSP	70.74	4.67	1.18	2.74	—	3.95	16.72	126.11	0.5	0.79	505	697	298
5	Western	74.56	5.31	0.99	0.46	—	11.47	7.2	186.78	0.52	0.91	400	400	600
6	Eastern	72.72	5.03	1.4	2.99	—	9.13	8.73	133	0.79	0.87	400	400	600

煤粉进料速率

/kg·h^-1

H₂O/煤粉

/g·g^-1

O₂/煤粉

/g·g^-1

压力

/MPa

文献［23］

现场用煤

编号	煤粉进料速率/g·s^-1	O₂·煤粉^-1/g·g^-1	H₂O·煤粉^-1/g·g^-1
Run 1	76.66	0.866	0.241
Run 2	81.18	0.768	0.318
Run 3	82.2	0.813	0.309
Run 4	79.46	0.807	0.323
Run 5	71.64	0.826	0.352
Run 6	87.73	0.774	0.291
Run 7	90.97	0.776	0.282
Run 8	92.13	0.797	0.247
Run 9	87.79	0.787	0.268
Run 10	129.77	0.835	0.276
Run 11	132.79	0.848	0.279

References 24

1	汪寿建. 现代煤气化技术发展趋势及应用综述[J]. 化工进展, 2016, 35(3): 653-664.
	WANG Shoujian. Development and application of modern coal gasification technology[J]. Chemical Industry and Engineering Progress, 2016, 35(3): 653-664.
2	刘永健, 何畅, 冯霄, 等. 煤制合成天然气装置能耗分析与节能途径探讨[J]. 化工进展, 2013, 32(1): 48-53, 103.
	LIU Yongjian, HE Chang, FENG Xiao, et al. Analysis of energy consumption and energy saving approach in a coal to SNG plant[J]. Chemical Industry and Engineering Progress, 2013, 32(1): 48-53, 103.
3	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.
4	LI X, GRACE J R, WATKINSON A P, et al. Equilibrium modeling of gasification: a free energy minimization approach and its application to a circulating fluidized bed coal gasifier[J]. Fuel, 2001, 80(2): 195-207.
5	KONG Xiangdong, ZHONG Weimin, DU Wenli, et al. Three stage equilibrium model for coal gasification in entrained flow gasifiers based on Aspen Plus[J]. Chinese Journal of Chemical Engineering, 2013, 21(1): 79-84.
6	SANCHEZ C, ARENAS E, CHEJNE F, et al. A new model for coal gasification on pressurized bubbling fluidized bed gasifiers[J]. Energy Conversion and Management, 2016, 126: 717-723.
7	WEN C Y, CHAUNG T Z. Entrainment coal gasification modeling[J]. Industrial & Engineering Chemistry, 1979, 18: 684-695.
8	LIU G S, REZAEI H R, LUCAS J A, et al. Modelling of a pressurised entrained flow coal gasifier: the effect of reaction kinetics and char structure[J]. Fuel, 2000, 79: 1767-1779.
9	ADEYEMI I, JANAJREH I. Modeling of the entrained flow gasification: kinetics-based Aspen Plus model[J]. Renewable Energy, 2015, 82: 77-84.
10	YOSHIDA H, KIYONO F, TAJIMA H, et al. Two-stage equilibrium model for a coal gasifier to predict the accurate carbon conversion in hydrogen production[J]. Fuel, 2008, 87: 2186-2193.
11	DOHERTY W, REYNOLDS A, KENNEDY D. The effect of air preheating in a biomass CFB gasifier using Aspen Plus simulation[J]. Biomass and Bioenergy, 2009, 33: 1158-1167.
12	ALSHAMMARI Y M, HELLGARDT K. Thermodynamic analysis of hydrogen production via hydrothermal gasification of hexadecane[J]. International Journal of Hydrogen Energy, 2012, 37: 5656-5664.
13	CHEN Z, DAI Z H, WANG F C. Simulation analysis of ammonia distribution in methanol production from coal water slurry gasification[J]. Journal of Coal Science and Engineering(China), 2013, 19(4): 546-553.
14	刘霞, 田原宇, 乔英云. 国内外气流床煤气化技术发展概述[J]. 化工进展, 2010, 29(S2): 120-124.
	LIU Xia, TIAN Yuanyu, QIAO Yingyun. Progress of entrained-bed coal gasification technology[J]. Chemical Industry and Engineering Progress, 2010, 29(S2): 120-124.
15	代正华, 龚欣, 王辅臣, 等. 气流床粉煤气化的Gibbs自由能最小化模拟[J]. 燃料化学学报, 2005, 33(2): 129-133.
	DAI Zhenghua, GONG Xin, WANG Fuchen, et al. Thermodynamic analysis of entrained-flow pulverized coal gasification by Gibbs free energy minimization[J]. Journal of Fuel Chemistry and Technology, 2005, 33(2): 129-133.
16	陈世豪, 曹志凯, 师佳, 等. 基于Aspen Plus的固定床煤气化稳态模拟方法研究[J]. 煤炭学报, 2012, 37(S1): 167-172.
	CHEN Shihao, CAO Zhikai, SHI Jia, et al. Steady-state simulation of fixed bed for coal gasification using Aspen Plus[J]. Journal of China Coal Society, 2012, 37(S1): 167-172.
17	刘忠慧, 于旷世, 张海霞, 等. 基于Aspen Plus的循环流化床工业气化炉模拟[J].化工进展, 2018, 37(5): 1709-1717.
	LIU Zhonghui, YU Kuangshi, ZHANG Haixia, et al. Simulation of industrial circulating fluidized bed gasifier by Aspen Plus[J]. Chemical Industry and Engineering Progress, 2018, 37(5): 1709-1717.
18	WEN C Y, CHEN H, ONOZAKI M. User's manual for computer simulation and design of the moving-bed coal gasifier[R]. Office of Scientific and Technical Information(OSTI), 1982.
19	SUDIRO M, PELLIZZARO M, BEZZO F, et al. Simulated moving bed technology applied to coal gasification[J]. Chemical Engineering Research and Design, 2010, 88: 465-475.
20	RENGANATHAN T, YADAV M V, PUSHPAVANAM S, et al. CO₂ utilization for gasification of carbonaceous feedstocks: a thermodynamic analysis[J]. Chemical Engineering Science, 2012, 83: 159-170.
21	GOVIND R, SHAH J. Modeling and simulation of an entrained flow coal gasifier[J]. AIChE Journal, 1984, 30(1): 79-92.
22	陈倩, 李士雨, 李金来, 等. 水煤浆气化过程的计算机模拟[J].计算机与应用化学, 2012, 29(12): 1425-1428.
	CHEN Qian, LI Shiyu, LI Jinlai, et al. Simulation of water-coal slurry gasification process[J]. Computers and Applied Chemistry, 2012, 29(12): 1425-1428.
23	孔祥东. 工业气流床水煤浆气化炉的建模、控制与优化研究[D].上海: 华东理工大学, 2014.
	KONG Xiangdong. Research on modeling, control and optimization for industrial entrained Flow coal gasification process[D]. Shanghai: East China University of Science and Technology, 2014.
24	LIU M, SHEN Z, LIANG Q, et al. Experimental studies on two dimensional particle swarm gasification of different coal chars and petroleum coke at high temperature[J]. Fuel, 2019, 241: 973-984.

[1]	XU Maoyu, TAO Shuai, QI Cong, LIANG Lin. Start-up and temperature fluctuation of loop heat pipe with flat disk evaporator [J]. Chemical Industry and Engineering Progress, 2023, 42(9): 4531-4537.
[2]	LUO Cheng, FAN Xiaoyong, ZHU Yonghong, TIAN Feng, CUI Louwei, DU Chongpeng, WANG Feili, LI Dong, ZHENG Hua’an. CFD simulation of liquid distribution in different distributors in medium-low temperature coal tar hydrogenation reactor [J]. Chemical Industry and Engineering Progress, 2023, 42(9): 4538-4549.
[3]	SHI Yu, ZHAO Yunchao, FAN Zhixuan, JIANG Dahua. Experimental study on the optimum phase change temperature of phase change roofs in hot summer and cold winter areas [J]. Chemical Industry and Engineering Progress, 2023, 42(9): 4828-4836.
[4]	CHEN Xiangyu, BIAN Chunlin, XIAO Benyi. Research progress on temperature phased anaerobic digestion technology [J]. Chemical Industry and Engineering Progress, 2023, 42(9): 4872-4881.
[5]	YANG Ying, HOU Haojie, HUANG Rui, CUI Yu, WANG Bing, LIU Jian, BAO Weiren, CHANG Liping, WANG Jiancheng, HAN Lina. Coal tar phenol-based carbon nanosphere prepared by Stöber method for adsorption of CO₂ [J]. Chemical Industry and Engineering Progress, 2023, 42(9): 5011-5018.
[6]	ZHAO Jian, ZHUO Zewen, DONG Hang, GAO Wenjian. A new method for observation of microstructure of waxy crude oil and its emulsion system [J]. Chemical Industry and Engineering Progress, 2023, 42(8): 4372-4384.
[7]	ZHANG Xuewei, HUANG Yaji, XU Yueyang, CHENG Haoqiang, ZHU Zhicheng, LI Jinlei, DING Xueyu, WANG Sheng, ZHANG Rongchu. Adsorption characteristics of SO₃ from coal flue gas by alkaline adsorbent [J]. Chemical Industry and Engineering Progress, 2023, 42(7): 3855-3864.
[8]	SUN Zhengnan, LI Hongjing, JING Guolin, ZHANG Funing, YAN Biao, LIU Xiaoyan. Application of EVA and its modified polymer in crude oil pour point depressant field [J]. Chemical Industry and Engineering Progress, 2023, 42(6): 2987-2998.
[9]	ZHAO Yi, YANG Zhen, ZHANG Xinwei, WANG Gang, YANG Xuan. Molecular simulation of self-healing behavior of asphalt under different crack damage and healing temperature [J]. Chemical Industry and Engineering Progress, 2023, 42(6): 3147-3156.
[10]	ZHANG Wei, QIN Chuan, XIE Kang, ZHOU Yunhe, DONG Mengyao, LI Jie, TANG Yunhao, MA Ying, SONG Jian. Application and performance enhancement challenges of H₂-SCR modified platinum-based catalysts for low-temperature denitrification [J]. Chemical Industry and Engineering Progress, 2023, 42(6): 2954-2962.
[11]	XU Xian, CUI Louwei, LIU Jie, SHI Junhe, ZHU Yonghong, LIU Jiaojiao, LIU Tao, ZHENG Hua’an, LI Dong. Effect of raw material composition on the development of semicoke mesophase structure [J]. Chemical Industry and Engineering Progress, 2023, 42(5): 2343-2352.
[12]	DAI Hang, GAO Ruixue, LI Yiguo, ZHU Jin, WANG Jinggang. Research progress on the synthesis of excellent impact and transparency polyesters with high glass transition temperature [J]. Chemical Industry and Engineering Progress, 2023, 42(5): 2555-2565.
[13]	ZHOU Yafeng, YANG Jiang, MA Cheng, LIU Hailing. Preparation and properties of heat resistant emulsion thickener for fracturing [J]. Chemical Industry and Engineering Progress, 2023, 42(5): 2647-2654.
[14]	LIU Guangping, LU Zhenneng, GONG Yulie. Dynamic response and disturbance optimization of high temperature heat pump steam systems [J]. Chemical Industry and Engineering Progress, 2023, 42(4): 1719-1727.
[15]	ZHAO Chongyang, ZHAO Lei, SHI Xiangwen, HUANG Jun, LI Zhiyao, SHEN Kai, ZHANG Yaping. Effect of O₂/H₂O/SO₂ on the adsorption of PbCl₂ by modified iron-rich attapulgite at high temperature [J]. Chemical Industry and Engineering Progress, 2023, 42(4): 2190-2200.