粉浆气化炉内流场分布数值模拟研究

Research on Numerical Simulation of Flow Field Distribution in Pulverized-Coal and Slurry Gasifier

为了深入分析粉浆耦合气化技术的反应机理,以粉浆气化炉为研究对象,分别建立了气化炉的热力学模型和动力学模型。基于Fluent软件,对气化炉内粉浆气化过程进行了数值模拟和优化分析,考察了炉侧水煤浆喷嘴入射角度的变化对气化性能的影响。结果表明:采用顶部喷嘴干粉进料的粉浆气化装置是可行的,该进料方式可有效保护气化炉拱顶不受高速气流冲击的影响;随着炉侧水煤浆喷嘴入射角度的减小,颗粒停留时间延长,碳转化率提高,合成气组分更理想,但炉侧水煤浆喷嘴入射角度不宜过小。

In order to deeply analyze the reaction mechanism of pulverized-coal and slurry coupled gasification technology,the thermodynamic model and dynamic model of the gasifier are established respectively,with taking the pulverized-coal and slurry gasifier as the research object.Based on Fluent software,the pulverized-coal and slurry gasification process in gasifier is numerically simulated and optimized,and the influence of incident angle of coal-water slurry nozzle at the furnace side on gasification performance is investigated.The results show that using the pulverized-coal and slurry gasification unit with dry powder feeding top-nozzle is feasible,and this feeding method can effectively protect the vault top of gasifier from the impact of high-speed gas flow.With the decrease of incident angle of coal-water slurry nozzle at the furnace side,the retention time of coal particles is prolonged,the carbon convention rate is increased,and the composition of syngas is more ideal,but the incident angle should not be too small.