蒸汽煤比及氧煤比对GSP煤粉气化和GE水煤浆气化过程的影响—基于Aspen Plus模拟的双因素分析比较研究

The combined effects of steam-coal ratio and oxygen-coal ratio on the process of GSP pulverized coal gasification and GE coal-water-slurry gasification——Comparative study of bifactor interaction based on aspen plus

利用Aspen Plus、基于Gibbs自由能最小化方法建立GSP煤粉气化模型及GE水煤浆气化模型,运用灵敏度分析工具,对比研究了蒸汽煤比及氧煤比双因素同时变化对2种气化炉的产气量、合成气组成、粗煤气氢碳比和煤气热值的影响。结果表明:采用Aspen Plus建立的气化炉模型模拟结果与生产数据吻合;与GE水煤浆气化相比,相同的氧煤比及蒸汽煤比条件下,GSP粉煤气化产生的有效气(CO+H2)含量高约8.4%;GSP和GE气化最佳氧煤比范围均在0.7 Kg/Kg^0.8 Kg/Kg;当氧煤比从0.5Kg/Kg增加至1.0 Kg/Kg,有效气含量随氧煤比的增加均呈先上升后下降的趋势,GSP有效气含量变化幅度达28%,而GE有效气含量变化仅18%;GE粗煤气中氢碳比约在0.56~1.03,GSP粗煤气中氢碳比约在0.22~0.52;相同氧煤比及蒸汽煤比范围内,GSP气化产生的煤气热值较高,氧煤比由0.5 Kg/Kg升至1.0 Kg/Kg,GSP煤气热值下降约35%,GE煤气热值下降约29%。相较于GE气化,GSP气化的有效气量大、粗煤气的氢碳比低、煤气热值高,气化过程受氧煤比的影响更为显著。

Both of GSP pulverized coal gasification and GE coal-water-slurry gasification were simulated based on methodology of Gibbs free energy minimization with the aid of Aspen Plus. The combined effects of steam-coal ratio and oxygen-coal ratio on yield, composition, HJCO and heat value of syngas for two different forms of gasification were comparatively investigated by using sensitivity model analysis. The results reveal that the simulated data of GSP and GE gasification are in good fit with actual operational results. Compared with GE gasification, the yield of syngas from GSP gasification is higher by 8.4% under the same conditions. The optimum ranges of oxygen-coal ratio for GSP and GE gasification cover the same range of 0.7 Kg/Kg～0.8 Kg/Kg. As oxygen-coal ratio is enhanced from 0.5 Kg/Kg to 1.0 Kg/Kg, the yield of syngas both rises at first and drops latter with 28% for GSP gasification and 18% for GE gasification, respectively. Besides, the ratio of H2/CO for GE syngas varies in the range of 0.56-1.03, and 0.22-0.52 for GSP gasification. With the increase of oxygen-coal ratio from 0.5 Kg/Kg to 1.0 Kg/Kg, the heat value of GSP gasification syngas decreases approximately 35%, and GE gasification declines nearly 29%. It could be concluded that compared with GE gasification, GSP gasification will result in a higher yield and heat value of syngas, lower H2/CO, and GSP gasification process is influenced stronger bv oxwen-coal ration.