摘要
厘清煤颗粒热解的内部温度变化和挥发分析出规律,是优化炉体结构和操作参数、进一步提升BGL煤气化经济性的基础。本文通过剖析BGL煤气化热解过程构建了煤颗粒热解模型,并利用文献实验数据验证了模型合理性。模型求解采用解耦算法,其中传热模型采用追赶法,热解动力学模型采用4阶单步递推法,环境温度由移动床一维模型计算。模拟结果表明:BGL煤气化热解终温较高,颗粒内部径向温度变化大;粒径取10mm,热解终温计算值1372K,煤颗粒表面和中心温差峰值计算值338K;粒径取40mm,相应计算值分别为1412K和381K;煤颗粒挥发分析出过程与气固非催化缩核反应过程相似,印证了煤热解过程受传热过程控制;热解动力学的描述以FZ通用热解模型适应性更好;移动床一维模型预测BGL煤气化热解层高度时,热解蒸发模型优于FZ通用热解模型,预测值为0.6165m,与搅拌器运行情况相符。
Research on the patterns of the internal temperature change and volatile analysis on the law of coal particle pyrolysis are essential to optimizing the furnace structure and operating parameters,while further improves the economy of BGL coal gasification.Based on the analysis of BGL coal gasification pyrolysis process,this study established the coal particle pyrolysis model.The decoupling algorithm was sadopted in solving the model,in which the heat transfer model adopted the chasing method,the pyrolysis kinetic model adopted the fourth-order single-step push-up method,and the ambient temperature was calculated by the moving bed one-dimensional model.The rationality of the model was verified by experimental data in literature.The simulation results show that the final pyrolysis temperature of BGL coal gasification is higher,and the temperature gradient inside the particles changes greatly.The particle size is 10 mm,the calculated final pyrolysis temperature is 1372 K,and the calculated peak temperature difference between the surface and center of coal particles is 338 K.Taking the particle size of 40 mm,the corresponding calculated values are 1412 K and 381 K respectively;The process of coal particle volatilization is similar to that of gas-solid non-catalytic condensation reaction,which proves that the coal pyrolysis process is controlled by heat transfer process.Pyrolysis kinetics is described by FZ general pyrolysis model,which has better adaptability than distributed activation energy model.When the moving bed one-dimensional model predicts the height of BGL coal gasification pyrolysis layer,the pyrolysis evaporation model is superior to FZ general pyrolysis model.The predicted height of pyrolysis layer is 0.6165 m,which is consistent with the operation of agitator.
作者
张利合
许德平
徐振刚
王永刚
Zhang Lihe;Xu Deping;Xu Zhengang;Wang Yonggang(School of Chemical and Environmental Engineering,China University of Mining and Technology-Beijing,Beijing 100083;Research Institute of Coal Chemical Industry,China National Coal Group Corporation,Beijing 100120)
出处
《矿业科学学报》
CSCD
2023年第2期232-241,共10页
Journal of Mining Science and Technology
基金
国家自然科学基金(42030807)。
关键词
BGL煤气化
煤颗粒
热解
数值模拟
BGL coal gasification
coal particle
pyrolysis
numerical simulation
