COREX熔化气化炉布料模式对煤气流分布的影响

Influence of burden distribution mode on the gas flow distribution in COREX melter gasifier

布料模式决定了料床的空隙度,而料床的空隙度分布决定了煤气流的第二次分布.通过建立二维的COREX-3000气化炉煤气流动的数学模型,以Fluent软件为载体,采用多孔介质模型描述了单环布料、多环布料两种不同布料模式下的料床内的煤气流动状况,获得了气化炉内煤气的速度场和压力场.结果表明:因布料过程在料面上发生的炉料粒度偏析造成的空隙度分布对煤气流分布的影响很大.在单环布料时,炉料堆尖处煤气流速很低,随着布料档位外移,气化炉整体压差呈现先增加后减小的趋势,拐点出现在3.0 m布料档位,可见炉料布料方式对煤气流有再分配的作用,较为适宜的布料档位为2.5～3.5 m,不宜低于2.0 m和超过4.0 m的档位.通过模拟计算获得的非均匀床层中气体流动规律的认识对COREX气化炉工艺有借鉴意义.

Charging mode determines the burden voidage which directly affects the second distribution of the gas flow.In this paper,a 2D mathematical model for gas flow was established to simulate the gas flow distribution under different modes,such as the single and multiple rings in COREX melter gasifier.Based on the Fluent software and the porous media method,the velocity field and pressure field were obtained.The results show that the voidage distribution caused by size segregation on the burden surface in the charging process has a significant effect on the gas flow distribution.In the single ring charging process,the gas velocity on the pile top is slow and the pressure difference increases first and then decreases with the migration outward of the charging gear,and the inflection point occurs in the position of 3.0 m.Thus,it can be seen that the charging mode has influence on the redistribution of gas flow.The proper position is between 2.5 and 3.5 m.It is not suitable for the position lower than 2.0 m and more than 4.0 m.The authors believe that the regulation above is available for the COREX process.