Patent ID: 7118820

Claim:
A fuel cell power plant ( 10 ) for generating electrical energy from a process oxidant stream ( 53 , 42 , 28 ) and a reducing fluid stream ( 26 ), the plant comprising: a) at least one fuel cell ( 12 ) for producing the electrical energy from the process oxidant stream ( 53 , 28 ) and the reducing fluid stream ( 26 ), and providing a fuel cell exhaust stream ( 48 ) containing moisture and sensible heat; b) an energy recovery device ( 32 ) having first and second gas flow channels ( 44 , 42 ) separated by a respective enthalpy exchange barrier ( 46 ), the fuel cell exhaust stream ( 48 ) connected to pass through the first gas flow channel ( 44 ) and a source of process oxidant ( 30 ) for the process oxidant stream ( 53 ) connected to pass through the second gas flow channel ( 42 ), thereby to allow mass and heat transfer between the gases in the first and second gas flow channels via the enthalpy exchange barrier; c) a supply of liquid medium ( 66 ); and d) means ( 58 , 60 ) for injecting the liquid medium ( 66 , 64 ) substantially directly into the process oxidant stream ( 53 ) preparatory to the process oxidant passing through the energy recovery device second gas flow channel ( 42 ) for regulating the transfer of mass and heat between the fuel cell exhaust stream ( 48 ) and the process oxidant stream ( 53 , 42 ).