二甲醚自热重整制氢过程的热力学分析

Thermodynamic Analysis of Hydrogen Production from Dimethyl Ether Auto-thermal Reforming

摘要:

对二甲醚自热重整制氢体系进行了热力学计算和分析，探讨了反应体系的理论最大能效以及达到热力学平衡时产物等的变化情况，分析了水醚摩尔比、氧醚摩尔比、反应温度等因素对体系平衡组成的影响.分析发现，固定水醚摩尔比时，二甲醚自热重整理论完全反应可在某一氧醚摩尔比下达到自热平衡点，此时反应能量效率最高；重整反应在水醚摩尔比为2.0~4.0、氧醚摩尔比为0.4~0.5以及温度为150~350 ℃的条件下，产物中氢气摩尔分数高于50%，氢气产率高于80%，产物中一氧化碳摩尔分数低于5%，反应理论最大能效高于85%.

Abstract:

The thermodynamic analysis of hydrogen production from dimethyl ether(DME) auto-thermal reforming was carried out in order to study the influences of the ratio of steam to DME,the ratio of oxygen to DME and temperature on equilibrium composition.Theoretical maximum energy efficiency and product fraction in the reaction system were analyzed.The results indicate the complete reaction for the thermo-neutral oxygen to DME ratio at a given steam to DME ratio,when the maximum theoretical efficiency can be arrived.The hydrogen mole fraction above 50% and its yield above 80% can be obtained under the conditions that the ratio of steam to DME is 2.0~4.0,oxygen to DME 0.4~0.5,the temperature is between 150~350 ℃,the carbon monoxide mole fraction is below 5% and theoretical maximum energy efficiency can be achieved 85%.