燃烧和反应

Gasification of Anthracite in a Pilot-Scale CFB Gasifier and Pore Structure Evolution of Gasification Fly Ash during Steam Activation

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  • 1. Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100190, China
    2. School of Energy, Power and Mechanical Engineering, North China Electric Power University, Beijing 102206, China
    3. University of Chinese Academy of Sciences, Beijing 100049, China

网络出版日期: 2023-10-24

基金资助

This work was financially supported by the Special Research Assistant Project, Chinese Academy of Sciences.

版权

Science Press, Institute of Engineering Thermophysics, CAS and Springer-Verlag GmbH Germany, part of Springer Nature 2023

Gasification of Anthracite in a Pilot-Scale CFB Gasifier and Pore Structure Evolution of Gasification Fly Ash during Steam Activation

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  • 1. Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100190, China
    2. School of Energy, Power and Mechanical Engineering, North China Electric Power University, Beijing 102206, China
    3. University of Chinese Academy of Sciences, Beijing 100049, China

Online published: 2023-10-24

Supported by

This work was financially supported by the Special Research Assistant Project, Chinese Academy of Sciences.

Copyright

Science Press, Institute of Engineering Thermophysics, CAS and Springer-Verlag GmbH Germany, part of Springer Nature 2023

摘要

迫切需要探索更多途径实现低活性无烟煤的大规模高值化利用。凭借较好的燃料适应性,循环流化床(CFB)气化技术在高质量利用无烟煤方面表现出一定潜力。本文基于中试规模的CFB气化炉,以产自中国山西的无烟煤为原料,开展了气化试验研究。试验表明,在1049℃操作温度和60.75%氧气浓度下,无烟煤CFB气化过程可以产生可燃物浓度为66%、低位热值为7.93 MJ/m的煤气。但是,由于大量气化飞灰(GFA)逃逸(逃逸率高达22%),该气化过程的整体气化效率并不理想:冷煤气效率低于48%,碳转化率仅为62%。进一步分析发现,该气化过程产生的GFA具有发达的孔结构,比表面积(SBET)达到277 m2/g,表明GFA具有用作活性炭(AC)或者AC前驱体的潜力。在此基础,对GFA开展了水蒸气活化实验。结果表明,升高活化温度可以加速活化进度,且不影响GFA的活化潜能。活化后的GFA的SBET最高提升63%,达到452 m2/g。并且,随着活化进行,GFA的孔结构呈现出发展、动态平衡和坍塌三个阶段的演化规律,根据碳损失率可以对其进行划分和量化。为实现GFA最佳活化效果,在活化过程中碳损失率应控制在约15%。本研究为无烟煤的高质量化利用提供了一种新方案。

本文引用格式

QI Xiaobin, YANG Qiyao, ZHAN Yueping, SONG Weijian, ZHU Zhiping, LYU Qinggang . Gasification of Anthracite in a Pilot-Scale CFB Gasifier and Pore Structure Evolution of Gasification Fly Ash during Steam Activation[J]. 热科学学报, 2023 , 32(5) : 1899 -1911 . DOI: 10.1007/s11630-023-1820-0

Abstract

The poor-reactivity anthracite urgently needs more ways for large-scale and high-quality utilization. Due to the advantage of good fuel adaptability, the circulating fluidized bed (CFB) gasification technology has the potential of high-quality utilization of anthracite. In this paper, one kind of anthracite from Shanxi province, China, was employed to be gasified in a pilot-scale CFB gasifier. It is found that at the operating temperature of 1049°C and oxygen concentration of 60.75%, the gas with a concentration of combustibles of 66% and a low heating value of 7.93 MJ/m3 (at about 25°C and 101.325 kPa) was produced in the CFB gasification process. However, the overall gasification efficiency was not desired because a large amount of gasification fly ash (GFA) escaped and its yield was up to 22%. In this case, the cold gas efficiency was below 48% and the carbon conversion ratio was only 62%. Further analysis reveals that the GFA was featured with a developed pore structure and the specific surface area (SBET) reached 277 m2/g. This indicates such GFA has a potential to use as activated carbon (AC) or AC precursor. Basis on this, steam activation experiments of the GFA produced were conducted to investigate the activation characteristics of GFA and thereby to determine its activation potential. Experimental results indicate that increasing temperature sharply accelerated the activation process, while did not impair the maximum activation effect. After activation, the SBET of GFA maximumly increased by 63%, reaching 452 m2/g. With the progress of activation, the pore structure of GFA presents a three-stage evolution process: development, dynamic balance, and collapse. Such a process can be divided and quantified according to the carbon loss. In order to achieve an optimal activation of GFA, the carbon loss shall be controlled at ~15%. This work provides a new scheme for high-quality utilization of anthracite.

参考文献

[1] Wang J., Kong L.X., Bai J., Xue K., Zhu X.L., Luo Y.D., Zhao X.P., Li H.Z., Guo Z.X., Bai Z.Q., Li W., Characterization of slag from anthracite gasification in moving bed slagging gasifier. Fuel, 2021, 292: 120390.
[2] Krishnamoorthy V., Pisupati S.V., A critical review of mineral matter related issues during gasification of coal in fixed, fluidized, and entrained flow gasifiers. Energies, 2015, 8(9): 10430–10463.
[3] Liu B., Peng B., Fang X., Liu Z., Comparison of gasification energy efficiency among coal-slurry entrained-flow gasifiers. Coal Conversion, 2018, 41(4): 62–66.
[4] Zheng J., Chi Y., Li J., Wang Y., Hu C., Feature of dioxin generation during gasification of solid waste containing high Cl in fluidized-bed. Journal of Chemical Industry and Engineering (China), 2012, 63(3): 910–915.
[5] Han L., Wang Q., Luo Z., Rong N., Deng G., H2 rich gas production via pressurized fluidized bed gasification of sawdust with in situ CO2 capture. Applied Energy, 2013, 109: 36–43.
[6] van Eyk P.J., Kosminski A., Mullinger P.J., Ashman P.J., Control of agglomeration during circulating fluidized bed gasification of a south Australian low-rank coal: Pilot scale testing. Energy & Fuels, 2016, 30(3): 1771–1782.
[7] Liang C., Zhang H., Zhu Z., Na Y., Lu Q., CO2-O2 gasification of a bituminous coal in circulating fluidized bed. Fuel, 2017, 200: 81–88.
[8] Zhang R., Liu D., Wang Q., Luo Z., Fang M., Cen K., Coal char gasification on a circulating fluidized bed for hydrogen generation: Experiments and simulation. Energy Technology, 2015, 3(10): 1059–1067.
[9] Li F., Li Z., Huang J., Fang Y., Understanding mineral behaviors during anthracite fluidized-bed gasification based on slag characteristics. Applied Energy, 2014, 131: 279–287.
[10] Chai Z., Zhu Z., Wang X., Wang K., Sulfur conversions during coal char gasification with a two-stage air supply in a pilot-scale circulating fluidized bed gasifier. Energy Sources Part A: Recovery, Utilization, and Environmental Effects, 2019, 42(4): 421–431.
[11] Xiao R., Shen L., Zhang M., Jin B., Xiong Y., Duan Y., Zhong Z., Zhou H., Chen X., Huang Y., Partial gasification of coal in a fluidized bed reactor: Comparison of a laboratory and pilot scale reactors. Korean Journal of Chemical Engineering, 2007, 24(1): 175–180.
[12] Yu K., Liu W., Zhang H., Zhu Z., Lü Q., Research on gasification of Shenhua coal and blended coal in industrial circulating fluidized bed gasifier. Proceedings of the CSEE, 2017, 37(20): 5980–5986.
[13] Zhang Y., Zhang H., Zhu Z., Na Y., Lu Q., Physicochemical properties and gasification reactivity of the ultrafine semi-char derived from a bench-scale fluidized bed gasifier. Journal of Thermal Science, 2017, 26(4): 362–370.
[14] Liu J., Zhu Z., Jiang H., Wang Y., Lu Q., Experimental study of oxygen-enriched gasification in circulating fluidized bed. Journal of Fuel Chemistry and Technology, 2014, 42(3): 297–302.
[15] Mahapatro A., Mahanta P., Gasification studies of low-grade Indian coal and biomass in a lab-scale pressurized circulating fluidized bed. Renewable Energy, 2020, 150: 1151–1159.
[16] Liu J., Experimental study on dual circulating fluidized beds gasification and oxygen-enriched gasification. University of Chinese Academy of Sciences, Beijing, China, 2014.
[17] Zhang Y., Study on high temperature combustion and melting characteristics of fine char from fluidized bed gasifier. University of Chinese Academy of Sciences, Beijing, China, 2018.
[18] Duan L.B., Liu D.Y., Chen X.P., Zhao C.S., Fly ash recirculation by bottom feeding on a circulating fluidized bed boiler co-burning coal sludge and coal. Applied Energy, 2012, 95: 295–299.
[19] Ren Q., Bao S., Combustion characteristics of ultrafine gasified semi-char in circulating fluidized bed. Canada Journal of Chemical Engineering, 2016, 94(9): 1676–1682.
[20] Sua-iam G., Makul N., Utilization of high volumes of unprocessed lignite-coal fly ash and rice husk ash in self-consolidating concrete. Journal of Cleaner Production, 2014, 78: 184–194.
[21] Wu T., Chi M., Huang R., Characteristics of CFBC fly ash and properties of cement-based composites with CFBC fly ash and coal-fired fly ash. Construction and Building Materials, 2014, 66: 172–180.
[22] Borowski G., Ozga M., Comparison of the processing conditions and the properties of granules made from fly ash of lignite and coal. Waste Management, 2020, 104: 192–197.
[23] Teixeira E.R., Camoes A., Branco F.G., Aguiar J.B., Fangueiro R., Recycling of biomass and coal fly ash as cement replacement material and its effect on hydration and carbonation of concrete. Waste Management, 2019, 94: 39–48.
[24] Buentello-Montoya D.A., Zhang X., Li J., The use of gasification solid products as catalysts for tar reforming. Renewable and Sustainable Energy Reviews, 2019, 107: 399–412.
[25] Hernandez J.J., Lapuerta M., Monedero E., Characterisation of residual char from biomass gasification: effect of the gasifier operating conditions. Journal of Cleaner Production, 2016, 138: 83–93.
[26] Li J., Chen Z., Li L., Qiao Y., Yuan Z., Zeng L., Li Z., Study on pore and chemical structure characteristics of atmospheric circulating fluidized bed coal gasification fly ash. Journal of Cleaner Production, 2021, 308: 127395.
[27] Song G., Song W., Qi X., Yang S., Effect of the air-preheated temperature on sodium transformation during Zhundong coal gasification in a circulating fluidized bed. Energy & Fuels, 2017, 31(4): 4461–4468.
[28] Wu Y.-H., Ma Y.-L., Sun Y.-G., Xue K., Ma Q.-L., Ma T., Ji W.-X., Graded synthesis of highly ordered MCM-41 and carbon/zeolite composite from coal gasification fine residue for crystal violet removal. Journal of Cleaner Production, 2020, 277: 123186.
[29] Wu Y.-H., Xue K., Ma Q.-L., Ma T., Ma Y.-L., Sun Y.-G., Ji W.-X., Removal of hazardous crystal violet dye by low-cost P-type zeolite/carbon composite obtained from in situ conversion of coal gasification fine slag. Microporous and Mesoporous Materials, 2021, 312: 110742.
[30] Kang Y., Wei X., Liu G., Mu M., Ma X., Gao Y., Zong Z., CO2-hierarchical activated carbon prepared from coal gasification residue: Adsorption equilibrium, isotherm, kinetic and thermodynamic studies for methylene blue removal. Chinese Journal of Chemical Engineering, 2020, 28(6): 1694–1700.
[31] Miao Z., Guo Z., Qiu G., Zhang Y., Wu J., Synthesis of activated carbon from high-ash coal gasification fine slag and their application to CO2 capture. Journal of CO2 Utilization, 2021, 50: 101585.
[32] Xu M., Wu Y., Zhang P., Liu Z., Hu Z., Lu Q., Green and moderate activation of coal fly ash and its application in selective catalytic reduction of NO with NH3. Environmental Science & Technology, 2022, 56(4): 2582–2592.
[33] Geldart D., Types of gas fluidization. Powder Technology, 1973, 7(5): 285–292.
[34] Monson P.A., Understanding adsorption/desorption hysteresis for fluids in mesoporous materials using simple molecular models and classical density functional theory. Microporous and Mesoporous Materials, 2012, 160: 47–66.
[35] Kovacik G., Wong B., Furimsky E., Preparation of activated carbon from western Canadian high rank coals. Fuel Processing Technology, 1995, 41(2): 89–99.
[36] Wu S., Huang S., Ji L., Wu Y., Gao J., Structure characteristics and gasification activity of residual carbon from entrained-flow coal gasification slag. Fuel, 2014, 122: 67–75.
[37] Bhatia S.K., Perlmutter D.D., A random pore model for fluid-solid reactions: I. Isothermal, kinetic control. AlChE Journal, 1980, 26(3):379–86.
[38] Bhatia S.K., Perlmutter D.D., A random pore model for fluid-solid reactions. 2. Diffusion and transport effects. AlChE Journal, 1981, 27(2): 247–254.
[39] Liu G., Benyon P., Benfell K.E., Bryant G.W., Tate A.G., Boyd R.K., Harris D.J., Wall T.F., The porous structure of bituminous coal chars and its influence on combustion and gasification under chemically controlled conditions. Fuel, 2000, 79(6): 617–626.
[40] Gu J., Wu S., Wu Y., Li Y., Gao J., Differences in gasification behaviors and related properties between entrained gasifier fly ash and coal char. Energy & Fuels, 2008, 22(6): 4029–4033.
[41] Tanner J., Bhattacharya S., Kinetics of CO2 and steam gasification of Victorian brown coal chars. Chemical Engineering Journal, 2016, 285: 331–340.
[42] Preciado-Hernandez J., Zhang J., Jones I., Zhu M., Zhang Z., Zhang D., An experimental study of gasification kinetics during steam activation of a spent tyre pyrolysis char. Journal of Environmental Chemical Engineering, 2021, 9(4): 105306.
[43] Mani T., Mahinpey N., Murugan P., Reaction kinetics and mass transfer studies of biomass char gasification with CO2. Chemical Engineering Science, 2011, 66(1): 36–41.
[44] Kim R.-G., Hwang C.-W., Jeon C.-H., Kinetics of coal char gasification with CO2: Impact of internal/external diffusion at high temperature and elevated pressure. Applied Energy, 2014, 129: 299–307.
[45] Huo W., Zhou Z., Wang F., Yu G., Mechanism analysis and experimental verification of pore diffusion on coke and coal char gasification with CO2. Chemical Engineering Journal, 2014, 244: 227–233.
[46] Li W.-W., Huang J.-J., Wang Z.-Q., Duan H.-W., Li J.-G., Fang Y.-T., Reaction kinetics of coal char gasification with CO2 and the effect of internal diffusion on the gasification. Journal of Fuel Chemistry and Technology, 2016, 44(12): 1416–1421.
[47] López G., Olazar M., Artetxe M., Amutio M., Elordi G., Bilbao J., Steam activation of pyrolytic tyre char at different temperatures. Journal of Analytical and Applied Pyrolysis, 2009, 85(1–2): 539–543.
[48] Jiang J., Manufactuing and application technology of activated carbon, Chemical Industry Press, Beijing, 2017.
[49] Li Y., Lu L., Lyu S., Xu H., Ren X., Levendis Y.A., Activated coke preparation by physical activation of coal and biomass co-carbonized chars. Journal of Analytical and Applied Pyrolysis, 2021, 156: 105137.
[50] Lu Z., Maroto-Valer M.M., Schobert H.H., Role of active sites in the steam activation of high unburned carbon fly ashes. Fuel, 2008, 87(12): 2598–2605.
[51] Zabaniotou A., Madau P., Oudenne P.D., Jung C.G., Delplancke M.P., Fontana A., Active carbon production from used tire in two-stage procedure: industrial pyrolysis and bench scale activation with H2O-CO2 mixture. Journal of Analytical and Applied Pyrolysis, 2004, 72(2): 289–297.
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