Applied Energy, Vol.148, 159-168, 2015
Conversion of methane by CO2 + H2O + CH4 plasma
A promising method of methane conversion by thermal plasma is presented. It allows syngas production with a set H-2/CO ratio of similar to 2.1 and with a similar to 95.2% H-2 + CO content. In comparison with other plasma methods, it differs in its high methane conversion level (91-98.3%), low energy consumption (31.8-35.9 MJ/kg) of converted methane and high selectivity on H-2 and CO. The influence of energy consumption and oxidizer excess on the key parameters of the process is studied. It is found that with a weak influence of heat losses and a volumetric flow of thermal energy (similar to 1 MW/m(3)), the optimum energy consumption is approximately 25.5-27.1 MJ/kg of injected methane and the optimum excess of oxidizer is 0-10%. The principal cause of the differences in experimental and calculated values is the wall influence (heat losses). The economic efficiency by combining the method and Fischer-Tropsch synthesis is estimated for the USA, and the profits of end-product sales have exceeded the expenses by similar to 67%. (C) 2015 Elsevier Ltd. All rights reserved.