Patent · US Expired

Method of removing scale from wet oxidation treatment apparatus

US4692252A · kind A · utility

31Cited by
5References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 24, 1986
Grant dateSep 8, 1987
Priority date
Expiry dateMar 24, 2006

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC23G1/00
  • WIPO fieldEnvironmental technology
  • WIPO sectorChemistry

Abstract

A method of removing scale from the surfaces of a fluid treatment apparatus by directing a base solution and an acid solution through the fluid treatment apparatus. The fluid treatment apparatus cleaned by the method of the present invention is a vertical tube wet oxidation treatment apparatus in which an aqueous slurry of organic materials is oxidized in a tube which extends deep into the surface of the earth. Water rinses are performed between the steps of circulating the aqueous base solution, circulating the aqueous acid solution, and operating the fluid treatment apparatus. The water used for separating the sequential steps is preferably buffered water. The aqueous acid solution is preferably a mineral acid and most preferably nitric acid. The aqueous base solution is preferably potassium hydroxide or sodium hydroxide. The method also contemplates a sectional wash of the apparatus by directing a base or acid solution partially into the apparatus.

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