煤质对水煤浆气化性能的影响研究

Study on the effect of coal properties on gasification performance of coal water slurry gasifier

煤质与气流床气化炉的匹配性至关重要,其不但影响气化炉的运行条件,也影响气化性能。选择了10种来自新疆和陕西北部的煤样进行了工业分析、元素分析、灰组成分析、灰熔点分析以及成浆性测试,并筛选出适合水煤浆气化的煤样。同时借助Aspen Plus软件对适合水煤浆气化的煤样在相同的煤浆浓度、碳转化率及操作压力条件下开展煤质对水煤浆气化性能影响的模拟分析。结果表明:煤中灰含量越高,冷煤气效率和有效气含量越低,比氧耗和比煤耗越高;煤中O/C质量比和H/C质量比的增加也会导致冷煤气效率和有效气含量降低,比氧耗和比煤耗增加。因此,从水煤浆气化经济性考虑,建议水煤浆气化煤质灰含量质量分数小于9.0%,煤中O/C质量比小于0.173,H/C质量比小于0.065。

Coal property is of great importance for entrained flow gasifier,which affects the operation conditions of the gasifier and gasification performance.Ten kinds of coal from Xinjiang and the northern of Shanxi province were selected to evaluate the effect of coal property on the coal water slurry gasification process.Based on the proximate and ultimate analysis,and tests of ash chemical compositions,ash fusion temperature and slurryability of ten coal samples,several samples that fit to entrained flow gasifier were selected to investigate the influence of coal property on gasification performance by using Aspen Plus software.The simulationswere performed at the same slurry concentration,carbon conversion rate and operating pressure.The results indicated that high ash content could cause the decrease of cold gas efficiency and syngas compositions,and the increase of specific oxygen and coal consumption.The increased O/C and H/C mass ratio in coals will also lead to the increase of specific oxygen and coal consumption and the decrease of cold gas efficiency and syngas compositions.Therefore,considering the economic of coal water slurry gasifiers,it is suggested that the ash content is less than 9.0%,O/C mass ratio in coal is less than 0.173,and H/C mass ratio in coal is less than 0.065.