Patent ID: 7146937

Claim:
In a direct-fired steam generator including a steam generator body defining a main combustion chamber having an outlet end through which hot gases are exhausted from the combustion chamber, a mixing chamber having an inlet end coupled for receiving the hot gases from the combustion chamber, and a water injection arrangement for injecting water into a zone at said outlet for being contacted by said hot gases and changed to steam, the improvement comprising: a first mounting flange fixed to said generator body in the vicinity of said outlet; a second mounting flange fixed to said mixing chamber at said inlet end; said first and second flanges being secured together to form a flange joint coupling said steam generator body to said mixing chamber; a water injection port being provided in one of said flanges; and a water passage being defined between said flanges in a location in fluid communication with said water injection port and extending completely about said zone; and at least one injection passage coupling said water passage to said zone for causing metering water into said zone for being changed to steam.