煤气化耦合C_1合成反应热力学分析

Thermodynamic Analysis of Coal Gasification Coupling C_1 Synthesis

提出了"煤气化与C1合成叠加耦合"的新工艺思想,即在煤气化过程中,使新生态的H2和CO在具有丰富孔隙结构的煤表面直接进行C1合成,并对这一新工艺进行了热力学分析。通过化学平衡的热力学分析发现,反应体系的独立反应数为9;生成各种烃的反应的吉布斯自由能变随温度变化的曲线斜率均为负值,升高温度有利于生成碳原子数多的烃,降低温度有利于生成碳原子数少的烃;平衡组成中C2～4烃的含量在900 K左右出现最大值;压力在一定范围内对平衡组成的影响比较明显,适当升高压力可提高烃的含量;增大n(H2O)∶n(C)不利于烯烃的生成。

A new process for the overlapped coupling between coal gasification and C1 synthesis was proposed,which was in the coal gasification process,hydrocarbons were synthesized from the newly generated carbon monoxide and hydrogen on the coal surface with porous structure.The thermodynamic analysis showed that there were nine independent reactions in the reaction system.Parameters of the independent reactions were obtained by atom matrix analysis.All the curve slopes of Gibbs free energy changes of the reactions with temperature were negative.The temperature rise was beneficial to synthesis of the hydrocarbons with more carbon atoms.C2-4 content in the equilibrium composition indicated the greatest value near 900 K.Appropriate increase of the pressure could raise the hydrocarbon content and the high feed mole ratio（n（H2O） ∶ n（C）） was unfavorable to the increase of the light olefin yield.