Handling of Acids from Compressed Oxyfuel-Derived CO2
AssigneeAir Products and Chemicals, Inc.
InventorsVincent White, Kevin Boyle Fogash, Francis Peter Petrocelli
Life of this patent
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Abstract
Sulfur dioxide (SO2) is removed from a carbon dioxide feed gas by maintaining the feed gas at elevated pressure(s) in the presence of oxygen (O2), water and NOx for a period of time sufficient to convert SO2 to sulfuric acid and NOx to nitric acid and produce SO2-depleted, NOx-lean carbon dioxide gas. The invention resides in separating the sulfuric and nitric acids from said SO2-depleted, NOx-lean carbon dioxide gas, and then neutralizing the acids by reaction with an alkaline sorbent in an acid/sorbent reactor system to produce sorbent-derive sulfate. The method has particular application in the removal of SO2 and NOx from flue gas produced by oxyfuel combustion of a carbonaceous fuel.
Claims24
A method for removing sulfur dioxide (SO2) from carbon dioxide feed gas comprising SO2 as a contaminant, said method comprising:
- maintaining said carbon dioxide feed gas, or a SO2-lean carbon dioxide gas derived therefrom, at elevated pressure(s) in a sour gas reactor system in the presence of oxygen (O2), water and NOx for a period of time sufficient to convert SO2 to sulfuric acid condensate and NOx to nitric acid condensate;
- separating said acid condensates from said carbon dioxide gas to produce SO2-depleted, NOx-lean carbon dioxide gas;
- and
- neutralizing at least a portion of said sulfuric acid condensate by reaction with an alkaline sorbent in an acid/sorbent reactor system to produce sorbent-derived sulfate.
Apparatus for removing SO2 from a carbon dioxide feed gas comprising SO2 as a contaminant, said apparatus comprising:
- a sour gas reactor system for maintaining said carbon dioxide feed gas, or a SO2-lean carbon dioxide gas derived therefrom, at elevated pressure(s) in the presence of O2, water and NOx for a period of time sufficient to convert SO2 to sulfuric acid condensate and NOx to nitric acid condensate;
- a first separation system for separating said acid condensates from said carbon dioxide gas to produce SO2-depleted, NOx-lean carbon dioxide gas;
- an acid/sorbent reactor system for neutralizing at least a portion of said sulfuric acid condensate by reaction with an alkaline sorbent to produce sorbent-derived sulfate;
- and
- a conduit arrangement for feeding said sulfuric acid condensate from said first separation system to said acid/sorbent reactor system.
Dependencies are inferred from the claim text.