Patent · US Expired

Method for removing mercury and sulfur dioxide from gases

US6284208A · kind A · utility

70Cited by
10References
4Claims
0Family size

Inventor

Key dates

Filing dateApr 14, 1999
Grant dateSep 4, 2001
Priority date
Expiry dateApr 14, 2019

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB01D53/64
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A process is provided for the removal of mercury and sulfur dioxide out a flue gas from, for example, power stations, smelters, waste incineration plants and crematories, by washing the flue gas with an oxidized, chloride-containing washing water, which may be sea water, which has been oxidized by either adding an oxidizing agent, such as sodium hypochlorite, or by passing an electric current through the washing water (which converts the chloride values into chlorine) so that the gaseous mercury is sorbed into the washing water and is converted into mercury (II) chloride complexes and the gaseous sulfur dioxide is sorbed into the washing water and converted into sulfuric acid, and subsequently passing the resulting mercury (II) chloride and sulfuric acid-containing washing water and the flue gas through a bed of calcium carbonate where the sulfuric acid and the calcium carbonate react to form calcium sulfate which is washed off the bed into the washing water. The calcium sulfate and mercury(II) chloride-containing washing water is collected in a sump and the cleaned flue gas is discarged from the process.

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