Patent · US Expired

Production of sulfur from sulfur dioxide obtained from flue gas

US4837001A · kind A · utility

4Cited by
6References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 27, 1987
Grant dateJun 6, 1989
Priority date
Expiry dateFeb 27, 2007

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC01D5/145
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

This invention is a regenerable process for producing elemental sulfur from SO.sub.2 initially contained in a dilute gas source by: (1) absorbing the SO.sub.2 in a concentrated Na.sub.2 SO.sub.3 solution to convert most of the Na.sub.2 SO.sub.3 to Na.sub.2 S.sub.2 O.sub.5 ; (2) separating one third of the absorbed SO.sub.2 ; (3) reacting the residual mixture with solid NaHCO.sub.3 to form gaseous carbon dioxide used in a subsequent step and a slurry composed of solid Na.sub.2 SO.sub.3 suspended in a Na.sub.2 SO.sub.3 solution; (4) separating solid Na.sub.2 SO.sub.3 from the solution which is recycled to (1) above; (5) reducing solid Na.sub.2 SO.sub.3 to Na.sub.2 S; (6) reacting the Na.sub.2 S with H.sub.2 O and CO.sub.2 to form solid NaHCO.sub.3 which is recycled to (3) above and gaseous H.sub.2 S; (6) reacting gaseous H.sub.2 S with SO.sub.2 separated in (2) above to form water and elemental sulfur.

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