Patent · US Expired

Method for removing sulphur dioxide from a gas

US5693301A · kind A · utility

6Cited by
4References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 30, 1996
Grant dateDec 2, 1997
Priority date
Expiry dateSep 30, 2016

Classification

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

Abstract

A method for removing sulphur dioxide from a gas, such as a flue gas, is disclosed. In the method, the sulphur-dioxide-containing gas is conducted upwards through at least one layer of aqueous absorbent suspension, whose absorbent is lime or limestone, the volume of the suspension layer being about 100-1000 l, calculated per m.sup.3 of sulphur-dioxide-containing gas flowing through the layer every second, the static height of the layer being at least about 20 mm, preferably about 300-600 mm, and the gas flow through the layer being such that turbulence is generated in the layer, that the pH of the absorbent suspension is adjusted to about 3.0-5.5 with the aid a buffer, preferably adipic acid, and that, separately from the sulphur-dioxide-containing gas, an oxygen-containing gas, preferably air, is supplied to the layer of absorbent suspension, preferably to the lower part of the layer of absorbent suspension and in such an amount that the molar ratio of oxygen to sulphur dioxide supplied to the suspension layer ranges from about 1:1 to about 25:1.

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