Patent · US Expired

Methods for producing hydrogen (BI) sulfide and/or removing metals

US6387669B1 · kind B1 · utility

7Cited by
8References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 5, 2000
Grant dateMay 14, 2002
Priority date
Expiry dateJan 5, 2020

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC02F2209/06
  • WIPO fieldEnvironmental technology
  • WIPO sectorChemistry

Abstract

The present invention is a process wherein sulfide production by bacteria is efficiently turned on and off, using pH adjustment. The adjustment of pH impacts sulfide production by bacteria by altering the relative amounts of H2S and HS— in solution and thereby control the inhibition of the bacterial metabolism that produces sulfide. This process can be used to make a bioreactor produce sulfide “on-demand” so that the production of sulfide can be matched to its use as a metal precipitation reagent. The present invention is of significance because it enables the use of a biological reactor, a cost effective sulfide production system, by making the biological reactor produce hydrogen sulfide “on demand”, and therefore responsive to production schedules, waste stream generation rate, and health and safety requirements/goals.

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