Combined Partial Oxidation and Carbon Dioxide Reforming Process: A Thermodynamic Study | Science Publications

American Journal of Applied Sciences

Sompop Jarungthammachote¹ 

关键词: Partial oxidation;    carbon dioxide reforming;    syngas production;    solid carbon formation;    greenhouse gases;    increasing temperature;    Fischer-Tropsch;    thermodynamic study;   

DOI  :  10.3844/ajassp.2011.9.14

学科分类：自然科学（综合）

来源: Science Publications

【 摘 要 】

Problem statement: CO₂ reforming is one of the methods to utilize a greenhouse gas toproduce syngas, an important feed for methanol and Fischer-Tropsch synthesis. However, CO₂reforming is strong endothermic reaction requiring large amount of supplied energy. Partial oxidation,an exothermic reaction, is combined with CO₂ reforming to serve the energy requirement. Thus, theoptimum ranges of O₂ and CO₂ fed to the process corresponding to feedstock are needed to find.Moreover, one of the most important problems found in this process is solid carbon formation.Therefore, the operating range in which the carbon formation can be avoided is also required to study.Approach: In this study CH₄ was used as feedstock. The optimum rage of O₂ and CO₂ fed to theprocess was found by using thermodynamic equilibrium method based on minimization of Gibbs freeenergy. The Lagrange multiplier method was conducted to form the equations and they were solved bythe Newton-Raphson method. The solid carbon formation zone was also simulated. Results: Thesimulation showed that higher reaction temperature caused higher CH₄ and CO₂ conversions. Syngasproduction increased with increasing temperature. Operating the process with high temperature or highO₂/CH₄ and CO₂/CH₄ rations could eliminate solid carbon formation. Increase of O₂/CH₄ ration higherthan 0.1 led decreasing syngas while increase of CO₂/CH₄ ration caused increasing H₂ and CO.However, when CO₂/CH₄ ration was higher than 0.85, increasing CO₂/CH₄ ration showed insignificantchange of syngas concentration. Conclusion: The combined partial oxidation and CO₂ reforming ofmethod should be operated with reaction temperature of 1050 K. The optimum range of CH₄:CO₂:O₂for this process is 1: 0.85-1.0:0.1-0.2.

【 授权许可】

Unknown