摘要 |
The ammonia content of fuel gas in an IGCC power generation system is reduced through ammonia decomposition, thereby reducing the NOx emissions from the plant. The power generation system includes a gasifier, a gas turbine and at least one catalytic reactor arranged between the gasifier and the gas turbine. The catalytic reactor may be either a three stage or two stage device. The three stage reactor includes a first catalyst which promotes water-gas-shift, a second catalyst which promotes CO methanation, and a third catalyst which promotes ammonia decomposition. The two stage reactor includes a first catalyst which promotes water-gas-shift and CO methanation and a second catalyst which promotes ammonia decomposition. The plural catalytic stages may be disposed in a single vessel or successively disposed in individual vessels, and the catalysts may be in a pelletized form or coated on honeycomb structures. Alternatively, fluidized bed reactors may be used. The reactions are carried out either adiabatically or non-adiabatically. Heat from the water-gas-shift and CO methanation reactions may be used to generate steam, which can be injected downstream or sent to a steam turbine. Preferably, a second catalytic reactor is provided in parallel with the first reactor so that the two reactors can alternately receive fuel gas from the gasifier.
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