Patent · US Expired

Method for simultaneous absorption of sulfur dioxide and nitric oxide from flue gas

US5433934A · kind A · utility

35Cited by
25References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 11, 1994
Grant dateJul 18, 1995
Priority date
Expiry dateJan 11, 2014

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02A50/20
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

The simultaneous abatement of NO and SO.sub.2 in flue gas is provided by an absorption process and apparatus utilizing an absorbent composition comprising an aqueous solution of chelates and sulfite salt for NO abatement and amine SO.sub.2 absorbents such as piperazinones, morpholinones, piperidines, piperazines, piperazinediones, hydantoins, triazinones, pyrimidinones, oxazolidones, etc. for SO.sub.2 abatement. SO.sub.2 is thermally stripped from the spent absorbent and recovered. Metal chelates oxidized to an inactive state as a side-reaction are electrochemically reduced. An anionic exchange membrane in the electrochemical cell regenerates heat stable amine salt byproducts to be converted back to useable amine sorbent, and facilitates removal from the absorbent solution of other waste salts.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.