加焦方式对气化炉炉料结构和气流分布的影响

Influence of coke charging patterns on burden structure and gas flow distribution in melter gasifier

装料模式决定了料床的孔隙度结构,进而决定了煤气流的分布信息。建立了气化炉炉料结构的离散单元模型和煤气流动的多孔介质模型,以自编程和软件Fluent为载体,结合两个模型共同描述了不同加焦方式对气化炉的炉料结构和煤气流动带来的变化,获得了炉内炉料结构的孔隙度分布信息和煤气的速度场、流线和质量通量。结果表明:首先,由离散单元模型获得的炉料结构信息可作为气流分布模型的边界条件输入;其次,煤气流模型的模拟结果表明焦柱的加入会在加焦位置处形成煤气发展通路,进而改善气化炉透气性,但应控制焦炭加入量,避免气流过度发展,进而影响煤气利用率。通过模拟计算获得的非均匀床层气体流动规律的认识对气化炉加焦工艺有借鉴意义。

Charging mode determines the burden voidage which directly affects the distribution of the gas flow.The discrete element model for burden structure and porous medium model for gas flow were established which were based on self-programming and Fluent software.Combined the two models,the changes of burden structure and gas flow distribution under different coke charging patterns in melter gasifier can be simulated meanwhile,gas velocity vectors,streamlines and mass flux were obtained.The results showed that the burden structure information calculated by the discrete element model can be used as the boundary conditions inputting into gas flow model.And the result of gas flow model indicated that gas passage ways was formed at the position of coke charging along the allcoke zone,which can improve the burden permeability.However,the addition amount of coke should be controlled to avoid gas excessive development,which can affect the utilization rate of gas.The inhomogeneous bed gas flow law calculated by the simulation can be used as reference in the coke charing patterns for melter gasifier.