Removal of acid mists
AssigneeAir Products and Chemicals, Inc.
InventorBarry Wayne Diamond
Life of this patent
Estimating the term…
Abstract
Acid mist may be removed efficiently from a gas stream using at least one fiber bed mist eliminator operating at elevated pressure of typically at least 2 bar (0.2 MPa), e.g. at about 4 bar (0.4 MPa) to about 50 bar (5 MPa). The invention has particular application in methods for processing carbon dioxide flue gas in which SO2 and/or NOx contaminants are converted at elevated pressure to sulfuric acid condensate and/or nitric acid condensate respectively.
Claims15
A method for removing acid mist from a gas stream, said method comprising passing said gas stream through at least one fiber bed mist eliminator to produce coalesced acid condensate and a gas stream that is at least substantially free of acid mist, wherein said gas stream is fed to said fiber bed mist eliminator(s) at an elevated pressure.
A method comprising:
- removing SO2 and NOx from a stream of carbon dioxide feed gas by maintaining said carbon dioxide feed gas in the presence of O2 and water at elevated pressure(s) in a reactor system for a period of time sufficient to convert SO2 to sulfuric acid and NOx to nitric acid to produce a stream of SO2-depleted, NOx-lean carbon dioxide gas and said sulfuric and nitric acids in the form of an acid condensate, a part of said acid condensate being suspended in said SO2-depleted, NOx-lean carbon dioxide gas as an acid mist;
- separating at least a portion of said acid condensate that is not suspended as acid mist from said stream of SO2-depleted, NOx-lean carbon dioxide gas;
- and
- removing said acid mist from said stream of SO2-depleted, NOx-lean carbon dioxide gas by passing said stream through at least one fiber bed mist eliminator to produce coalesced acid condensate and a stream of SO2-depleted, NOx-lean carbon dioxide gas that is at least substantially free of said acid mist, wherein said stream of SO2-depleted, NOx-lean carbon dioxide gas is fed to said fiber bed mist eliminator(s) at an elevated pressure;
- and
- recycling said coalesced acid condensate within said reactor system.
Apparatus for removing acid mist from a gas stream, said apparatus comprising:
- a pressurizable vessel suitable for operating at an elevated pressure, said vessel comprising an interior divided into a first zone and a second zone by a partition wall;
- a gas inlet to said first zone, and a gas outlet from said second zone;
- at least one fiber bed mist eliminator mounted on said partition wall providing a gas flow path from said first zone to said second zone;
- and
- a liquid outlet for removing coalesced acid condensate from said second zone.
Apparatus comprising:
- a reactor system for removing SO2 and NOx from carbon dioxide feed gas comprising SO2 and NOx as contaminants by maintaining said feed gas at elevated pressure(s) in the presence of O2 and water for a period of time sufficient to convert SO2 to sulfuric acid and NOx to nitric acid to produce SO2-depleted, NOx-lean carbon dioxide gas and said sulfuric and nitric acids as an acid condensate;
- and
- a separation system for separating acid condensate that is not in the form of an acid mist from a stream of SO2-depleted, NOx-lean carbon dioxide gas,
- wherein said reactor system comprises:
- a pressurizable vessel suitable for operating at an elevated pressure, said vessel comprising an interior divided into a first zone and a second zone by a partition wall;
- a gas inlet to said first zone, and a gas outlet from said second zone;
- at least one fiber bed mist eliminator mounted on said partition wall providing a gas flow path from said first zone to said second zone;
- a liquid outlet for removing coalesced acid condensate from said second zone;
- and
- a conduit arrangement for recycling coalesced acid condensate from said liquid outlet within said reactor system.
Dependencies are inferred from the claim text.