CATALYTICALLY STABILIZED COMBUSTION OF CH_4 IN ZERO EMISSION PROCESSES

摘要

A number of Zero Emission Power (ZEP) concepts for gas turbines mitigate NO_x and CO_2 emissions by combusting natural gas/oxygen mixtures with large quantities of recycled exhaust gas (CO_2 and H_2O). The resultant high degree of dilution narrows considerably the stable combustion operation window, which can again be extended by the addition of an upstream catalytic combustion stage. Therefore, we have chosen a concept consisting of an upstream heterogeneous followed by a subsequent homogeneous combustion zone. The catalytic stage is fed with a fuel-rich methane oxygen mixture and stabilizes the highly-diluted downstream gaseous flame by producing syngas. The goal is to maximize the hydrogen yield in the catalyst. Kinetic modeling can help to develop such a catalyst by analyzing which system and operational parameters have the greatest impact on syngas selectivity.