초록 ▼

A heat exchanger uses the heat from processed fuel gas from a reformer for a fuel cell to superheat steam, to preheat raw fuel prior to entering the reformer and to heat a water-steam coolant mixture from the fuel cells. The processed fuel gas temperature is thus lowered to a level useful in the fue

A heat exchanger uses the heat from processed fuel gas from a reformer for a fuel cell to superheat steam, to preheat raw fuel prior to entering the reformer and to heat a water-steam coolant mixture from the fuel cells. The processed fuel gas temperature is thus lowered to a level useful in the fuel cell reaction. The four temperature adjustments are accomplished in a single heat exchanger with only three heat transfer cores. The heat exchanger is preheated by circulating coolant and purge steam from the power section during startup of the latter.

대표청구항 ▼

A method of operating a heat exchanger in a fuel cell power plant, said method comprising the steps of: (a) providing a single heat exchanger housing having an inlet end, and outlet end and a medial portion between said inlet and outlet ends; (b) flowing reformed fuel from a reformer through said ho

A method of operating a heat exchanger in a fuel cell power plant, said method comprising the steps of: (a) providing a single heat exchanger housing having an inlet end, and outlet end and a medial portion between said inlet and outlet ends; (b) flowing reformed fuel from a reformer through said housing from said inlet end to said outlet end; (c) flowing raw hydrocarbon fuel through said housing from said outlet end to said inlet end in heat exchange relationship with said reformed fuel; (d) flowing coolant water from a power section of the power plant through said housing from said outlet end to said medial portion in heat exchange relationship with said reformed fuel; (e) flowing steam from the power plant through said housing from said medial portion to said inlet end in heat exchange relationship with said reformed fuel; and (f) said reformed fuel entering said inlet end at reformer temperatures and exiting said outlet end at power plant power section temperatures, said raw hydrocarbon fuel entering said outlet end at near ambient temperatures and exiting said inlet end at reformer temperatures, said coolant water entering said outlet end at power section temperatures and exiting said medial portion as two phase water-steam mixture, and said steam entering said medial portion at steam separator temperatures and exiting said inlet end at reformer temperatures.