Patent · US Expired

Effluent precipitation and neutralization vessel and method

US5792347A · kind A · utility

1Cited by
11References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 10, 1997
Grant dateAug 11, 1998
Priority date
Expiry dateApr 10, 2017

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB01D21/0003
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A neutral dischargeable effluent is developed by reaction between an acidic, spent photographic fixer liquid and an alkaline, spent photographic developer liquid; the spent fixer liquid contains iron in solution, the iron being introduced in a de-silvering pretreatment of the spent fixer liquid. The two liquids are fed into a treatment chamber and are allowed to react in the treatment chamber to form a neutral liquid and precipitated iron-containing solids; the solids settle in the treatment chamber and the neutral liquid rises upwardly through a synthetic organic polymer fiber filter pad into a discharge chamber above the filter pad; fine sticky particles suspended in the rising neutral liquid are retained by the filter pad; a neutral effluent is discharged from the discharge chamber.

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