Numerical study on the coal gasification characteristics in an entrained flow coal gasifier
Numerical study on the coal gasification characteristics in an entrained flow coal gasifier
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DOI：
10.1016/s0016-2361(01)00101-6
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发表时间：
2001-12-01
期刊：
影响因子：
7.4
通讯作者：
Lee, JG
中科院分区：
文献类型：
--
作者：
Choi, YC;Li, XY;Lee, JG
对浆状进料旋流煤气化炉的气化过程进行了数值预测。通过将复杂的煤气化过程简化为煤浆蒸发、煤的挥发分脱除和两相反应、湍流与两相传热耦合等几个阶段，建立了一个完整的煤气化过程数值模拟模型。气相流动采用k-ε湍流模型，颗粒运动采用随机轨道模型。分别采用未反应核收缩模型和修正的涡破裂（EBU）模型对非均相反应和均相反应进行了模拟。模拟结果获得了气化炉内流场、温度和组分浓度分布的详细信息。同时，模拟结果与实验数据进行了比较，作为一个功能的O-2/煤比。结果表明，碳转化率的计算值与实测值吻合较好，且随着O-2/煤比的增加，合成气质量的实测值优于计算值。这一结果与气化炉的总热损失和非均相反应动力学的不确定性有关。(C)2001爱思唯尔科技有限公司版权所有。
The coal gasification process of a slurry feed type, entrained-flow coal gasifier was numerically predicted in this paper. By dividing the complicated coal gasification process into several simplified stages such as slurry evaporation, coal devolatilization and two-phase reactions coupled with turbulent flow and two-phase heat transfer, a comprehensive numerical model was constructed to simulate the coal gasification process. The k-epsilon turbulence model was used for the gas phase flow while the Random-Trajectory model was applied to describe the behavior of the coal slurry particles. The unreacted-core shrinking model and modified Eddy break-up (EBU) model, were used to simulate the heterogeneous and homogeneous reactions, respectively. The simulation results obtained the detailed information about the flow field, temperature and species concentration distributions inside the gasifier. Meanwhile, the simulation results were compared with the experimental data as a function of O-2/coal ratio. It illustrated that the calculated carbon conversions agreed with the measured ones and that the measured quality of the syngas was better than the calculated one when the O-2/coal ratio increases. This result was related with the total heat loss through the gasifier and uncertain kinetics for the heterogeneous reactions. (C) 2001 Elsevier Science Ltd. All rights reserved.