Waste heat recovery boiler apparatus

Claim 1

A waste heat recovery boiler apparatus for generating steam by utilizing the heat of exhaust gases of a gas turbine machine, comprising: passage means connected at one end thereof to the gas turbine machine, said exhaust gases passing through said passage means; means, arranged in said passage means, for preheating feed water; evaporator means, arranged in said passage means and disposed on the upstream side of said preheater means, for vaporizing the preheated feed water; means, arranged in said passage means and disposed on the upstream side of said evaporator means, for super heating the vaporized saturated steam to generate super heated steam; means, arranged in a zone in said passage means and adjacent to said evaporator means, for removing oxides of nitrogen from the exhaust gases, said exhaust gases in said zone having a temperature in the range between 300° and 400° C; means, arranged in said nitrogen oxide-removing means, for injecting ammonia gas into the exhaust gases; and catalytic reaction means, arranged in said nitrogen oxide-removing means and disposed on the downstream side of said injection means, for reaction with a mixture of said ammonia gas and said exhaust gases to thereby decompose by reduction the oxides of nitrogen in the exhaust gases into nitrogen and steam, wherein said catalytic reaction means further comprises a plurality of chambers, arranged in said catalytic reaction means, each of said chambers havng therin a catalyst layer and being divided into two compartments, one of said two compartments communicating with a portion of said passage means disposed on the upstream side of said nitrogen oxide-removing means and the other of said two compartments communicating with a portion of said passage means disposed on the downstream side of said nitrogen oxide-removing means.