CPFD simulation on entrained-flow gasifier

doi:10.11949/0438-1157.20190376

Abstract

Abstract:

For the first time, the three-dimensional, full-size entrained flow gasifier was simulated by CPFD（computational particle fluid dynamics） simulation method, and a gasification simulation model suitable for CPFD simulation was established. This validated the model and CPFD simulation used in entrained-flow gasification. The detailed reaction process and the probability distribution of particle residence time were obtained through CPFD simulation. The results show that both particle short-circuit and re-circulation exist in the gasifier using single burner at top. The short-circuit flow is mainly located at the central region of the gasifier. In addition, the particle reaction rate is very fast in the central region but relatively slow near the wall region. Besides, the first amount of particles flowing out of the gasifier mainly consists of the fully-reacted particles.

Key words: entrained-flow, gasifier, CPFD simulation, gasification process, particle residence time

摘要：

利用CPFD(computational particle fluid dynamics)模拟方法对三维、全尺寸的气流床气化炉进行了模拟计算，建立起了适用于CPFD模拟方法的气化模拟模型。模拟结果与实验数据相一致，说明模型基本准确且CPFD模拟方法适用于气流床气化过程的模拟。借由CPFD模拟方法给出了颗粒相在气化炉中的具体反应历程及颗粒停留时间的概率分布；结果表明，在单喷嘴顶喷的气化炉中，同时存在颗粒相的轴向流动短路及返混，短路主要发生在炉中心区域；颗粒在炉中心区域反应剧烈而边壁区域反应则很缓慢，而且从气化炉流出的第一股短路颗粒主要由充分反应了的粉煤颗粒构成。

关键词: 气流床, 气化炉, CPFD模拟, 气化反应, 颗粒停留时间

CLC Number:

TQ 54

Yongshi LIANG, Xianglong ZHAO, Qiang QIN, Cliff Y GUO, Yi CHENG. CPFD simulation on entrained-flow gasifier[J]. CIESC Journal, 2019, 70(9): 3291-3299.

梁咏诗, 赵香龙, 秦强, 郭屹, 程易. 气流床气化炉的CPFD数值模拟[J]. 化工学报, 2019, 70(9): 3291-3299.

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