초록 ▼

Disclosed herein is a power generation process in which a portion of the carbon dioxide generated by gaseous fuel combustion is recycled back to the power generation process, either pre-combustion, post-combustion, or both. The power generation process of the invention may be a combined cycle proces

Disclosed herein is a power generation process in which a portion of the carbon dioxide generated by gaseous fuel combustion is recycled back to the power generation process, either pre-combustion, post-combustion, or both. The power generation process of the invention may be a combined cycle process or a traditional power generation process. The process utilizes sweep-based membrane separation.

대표청구항 ▼

1. A process for controlling carbon dioxide exhaust from combustion of a gaseous fuel, comprising: (a) performing a combustion step by combusting a mixture comprising a gaseous fuel and an oxygen-containing gas in a combustor, thereby generating a combustor exhaust stream comprising carbon dioxide a

1. A process for controlling carbon dioxide exhaust from combustion of a gaseous fuel, comprising: (a) performing a combustion step by combusting a mixture comprising a gaseous fuel and an oxygen-containing gas in a combustor, thereby generating a combustor exhaust stream comprising carbon dioxide and nitrogen;(b) routing the combustor exhaust stream as at least a portion of a working gas stream to a gas turbine, thereby generating electrical power and creating a turbine exhaust stream;(c) providing a first membrane having a first feed side and a first permeate side, and being selectively permeable to carbon dioxide over nitrogen and to carbon dioxide over oxygen;(d) passing at least a portion of the turbine exhaust stream across the first feed side;(e) withdrawing from the first permeate side a partially concentrated carbon dioxide first permeate stream;(f) withdrawing from the first feed side a carbon dioxide-depleted first residue stream;(g) providing a second membrane having a second feed side and a second permeate side, and being selectively permeable to carbon dioxide over nitrogen and to carbon dioxide over oxygen;(h) passing the first residue stream across the second feed side;(i) passing air, oxygen-enriched air, or oxygen as a sweep stream across the second permeate side;(j) withdrawing from the second feed side a second residue stream that is depleted in carbon dioxide compared to the first residue stream;(k) withdrawing from the second permeate side a second permeate stream comprising oxygen and carbon dioxide; and(l) passing at least a portion of the second permeate stream to a location between the combustor and the gas turbine as part of the working gas stream. 2. The process of claim 1, wherein the oxygen-containing gas comprises at least 15 volume % oxygen. 3. The process of claim 1, wherein the combustor exhaust stream comprises at least 2 volume % oxygen. 4. The process of claim 1, wherein the process recovers at least 80 volume % of the carbon dioxide generated by the combustion step into the partially concentrated carbon dioxide first permeate stream. 5. The process of claim 1, wherein the partially concentrated carbon dioxide first permeate stream contains at least 20 volume % carbon dioxide. 6. The process of claim 1, wherein the first membrane and the second membrane exhibit a selectivity for carbon dioxide over oxygen of at least 10.