两段式水煤浆气化模拟计算分析

Simulation calculation and analysis oftwo-stage coal water slurry gasification

用Aspen Plus过程模拟软件建立了以水煤浆和纯氧为原料的气流床数学模型,模拟计算了两段式水煤浆气化造气过程。利用该模型研究了水煤浆浓度、氧煤比、Ⅱ段煤浆分配比例对煤气化指标的影响。结果显示:水煤浆浓度的升高,会增加Ⅰ段、Ⅱ段有效气产量;氧煤比与Ⅱ段煤浆分配比例的升高会导致Ⅰ段有效气流量降低,Ⅱ段有效气流量先升高后降低;Ⅱ段出口甲烷干基含量随着炉温的降低而升高。对于生产合成天然气(SNG)以及整体煤气化联合循环(IGCC)装置,两段式水煤浆气化比较合适。

Based on Aspen Plus,a mathematical model of entrained flow two-stage slurry gasifier with CWS(coal water slurry)and pure oxygen as feedstocks is established,and the two-stage CWS gasification process is simulated and calculated.The influences of CWS concentration,oxygen coal ratio and sectionⅡcoal slurry distribution ratio on coal gasification index are studied by using the model.The results show that the increase of slurry concentration will increase the effective gas flow of sectionⅠandⅡ.The increase of oxygen coal ratio and coal slurry distribution ratio of sectionⅡwill lead to the decrease of effective gas flow in sectionⅠ.Effective gas flow in section II will increase firstly and then decrease.The dry methane content at the outlet of sectionⅡgasifier will increase with the decrease of furnace temperature.For SNG and IGCC unit,two-stage CWS gasification is more suitable.