US 7,067,211 B2 · Cogeneration system for a fuel cell

Abstract

A fuel cell system and process using an organic Rankine cycle to produce shaft work to operate a fuel cell system component such as an air compressor. The air compressor delivers compressed air to a fuel cell stack. The steps of the Rankine cycle include pumping a liquid working fluid to an elevated pressure, heating the fluid to a gas, expanding the high temperature and high-pressure gas through an expander to produce shaft work used to drive a fuel cell system component such as an air compressor, and then removing energy from the cooling fluid to change the gas back to a liquid, and repeating the cycle. The liquid fluid can be heated by an external boiler, or one of the components of the fuel cell system such as the combustor and/or the fuel cell stack.

Claims9

Dependent claims

A process comprising:

circulating a working fluid through a first flow path, wherein the working fluid comprises molecules comprising carbon;
pumping the working fluid in liquid form to an elevated pressure;
flowing the working fluid through the center of a bipolar plate in a fuel cell stack;
heating the working fluid to a high temperature and high-pressure gas;
expanding the high temperature and high-pressure gas through an expander to produce shaft work;
using the shaft work to drive an air compressor for compressing air and delivering compressed air to a fuel cell subcomponent;
and removing energy from the gas to change the gas to the working fluid in liquid form;
and flowing hydrogen through a second flow path including the fuel cell stack to generate electricity using the hydrogen, and wherein the first flow path does not include a steam reforming reactor to reform the working fluid.

5 more elements

Dependencies are inferred from the claim text.

Cogeneration system for a fuel cell

Life of this patent

Cogeneration system for a fuel cell

Life of this patent

Abstract

Claims9