Mitigation of NOx in Integrated Power Production

摘要

Systems and methods are provided for capturing CO2 from a combustion source using molten carbonate fuel cells (MCFCs). The fuel cells are operated to have a reduced anode fuel utilization. Optionally, at least a portion of the anode exhaust is recycled for use as a fuel for the combustion source. Optionally, a second portion of the anode exhaust is recycled for use as part of an anode input stream. This can allow for a reduction in the amount of fuel cell area required for separating CO2 from the combustion source exhaust and/or modifications in how the fuel cells are operated.

主权项

1. A method for producing electricity using a molten carbonate fuel having an anode and a cathode, the method comprising:
introducing a combustion fuel stream and an O2-containing stream into a combustion zone; performing a combustion reaction in the combustion zone to generate a combustion exhaust, the combustion exhaust comprising at least about 20 vppm of NOx; introducing an anode fuel stream comprising a reformable fuel into the anode of the molten carbonate fuel cell, an internal reforming element associated with the anode of the molten carbonate fuel cell, or a combination thereof; introducing a cathode inlet stream comprising at least a portion of the combustion exhaust into the cathode of the molten carbonate fuel cell, the cathode inlet stream comprising CO2, O2, and at least about 20 vppm of a nitrogen oxide; generating a) electricity within the molten carbonate fuel cell, b) an anode exhaust comprising H2 and CO2, and c) a cathode exhaust comprising less than about half of the NOx content of the cathode inlet stream; and separating at least a portion of the anode exhaust to form a CO2-enriched anode exhaust stream having a higher CO2 content than the anode exhaust and a CO2-depleted anode exhaust stream having a lower CO2 content than the anode exhaust.