Using a Plasma Fuel Reformer to Extend Combustion Lean Limits

InEnTec will develop a low temperature plasma reformer to extend combustion lean flammability limits. Improved power generation flexibility is one of the main requirements to increase the amount of renewables in the electric grid and improve the profitability of power plants reducing electricity costs for everyone. The window of operation of gas turbines used in power generation is limited by the flammability of the air/fuel mixture, known as the lean limit. Extending lean limits allows higher turndown ratios and fast ramp down ratios. Furthermore, extended lean limits can be used to significantly reduce NOx emissions. It has been known that hydrogen addition can be used to extend the lean limit, but practical units have not been commercialized to date. The purpose of this program is to build upon plasma-based reformers that have been found practical for smaller, automotive applications, operating at atmospheric pressure. The plasma reformer to be developed in this program will operate at 13-15 bar, under partial oxidation (rich combustion), and should enable turndown ratios of 10 to 1, and small enough to fit inside a combustor or upstream of one in the fuel line. The plasma reformer will normally be off, wasting no electrical power to run it but the power would turn on when the device (gas turbine, boiler or furnace) needs to go to low load. Phase I will focus mainly on designing and testing the plasmatron device under pressure. In Phase II, in cooperation with MIT, the device will be integrated and tested with a combustor. In Phase III, we will partner with a gas turbine OEM to develop and pilot a full scale commercial gas turbine generator combustion system.