Method for reducing industrial or urban effluent COD
US5112501A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 5, 1990 |
| Grant date | May 12, 1992 |
| Priority date | — |
| Expiry date | Mar 5, 2010 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC02F1/5263
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
A method for reducing industrial or urban effluent COD is described, comprising treating said effluents with an aqueous solution of alkaline and/or ammonium salts or humic acids perpared by the dry oxidation of coal with oxygen or oxygen/nitrogen mixtures at a temperture of between 120 and 350.degree. C. at an oxygen partial pressure of between 0.1 and 10 ata for a contact time of between 15 and 600 minutes, followed by extraction of the crude oxidation product with an alkaline and/or ammoniacal solution, characterised in that said aqueous solution is fed into effluent, the pH of which has been previously adjusted to between 1 and 3.5, to the extent that the humic acid salts which exhibit flocculating action are in a concentration of less than or equal to 2000 mg/1 of effluent.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.