Patent · US Expired

Removal of hydrogen sulfide from anaerobic digester gas

US5916438A · kind A · utility

4Cited by
9References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 1, 1994
Grant dateJun 29, 1999
Priority date
Expiry dateJul 1, 2014

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S210/916
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

The effluent gas stream from anaerobic waste water treatment digesters is treated to remove trace amounts of hydrogen sulfide and other contaminants. The chemical equation involved relies on the reaction of hydrogen sulfide with oxygen to form water plus elemental sulfur. The removal system includes a variable control line for adding air to the effluent gas stream; a filter for removing solids, entrained liquids and bacteria from the oxygen-enriched gas stream; a blower for directing the filtered gas stream into a potassium promoted activated carbon bed wherein the above chemical reaction takes place; and sensors for measuring the content of oxygen and hydrogen sulfide at the entrance and exit of the activated carbon bed. When the hydrogen sulfide content of the exiting gas stream exceeds a predetermined level, the amount of air added to the gas stream is increased until the predetermined level of hydrogen sulfide is achieved in the exiting gas stream.

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