Hybrid cycle SOFC-inverted gas turbine with CO2 separation

摘要

A new gas turbine-fuel cell Hybrid Cycle is proposed. The fuel cell advantageously operates close or under atmospheric pressure and is fully integrated with the gas turbine that is based on an Inverted Brayton-Joule Cycle. The idea of the invention is to capitalize on the intrinsic oxygen-nitrogen separation characteristic of the fuel cell electrolyte by sending to the Inverted Brayton-Joule Cycle only the anodic flow, which is the one free of nitrogen. In this way the flow that expands in the turbine consists only in steam and carbon dioxide. After the expansion the steam can be easily condensed, separated and pumped up. Therefore the compressor has mainly only to compress the separated carbon dioxide. This effect generates a substantial advantage in term of efficiency and enables separating the carbon dioxide. The new proposed Hybrid Cycle enables to: substantially increase the system efficiency compared to the known gas turbine-fuel cell Hybrid Cycle, maintain the fuel cell operating under or close to atmospheric pressure and separate the carbon dioxide.

主权项

1. A hybrid power generation system comprising a fuel cell including an anode, a cathode, an anodic turbine, and an anodic fluid line,wherein the anodic fluid line comprises:
said anode, a combustor, said anodic turbine, a compressor downstream of said anodic turbine, a separator located between said anodic turbine and said compressor, an anodic flow consisting only of carbon dioxide and water flowing from said anode through said combustor and said anodic turbine; said system further comprising an Inverted Brayton cycle downstream of said anode, and a cathodic fluid line consisting of at least said cathode and a cathodic flow flowing to and from said cathode; and wherein said fluid lines are separated from each other such that a portion of the anodic line between said anode and said separator is free of nitrogen from the cathodic fluid line.