Purification of waste streams containing available chlorine
US4175038A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 21, 1978 |
| Grant date | Nov 20, 1979 |
| Priority date | — |
| Expiry date | Jul 21, 1998 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC02F1/76
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
A process is disclosed for reducing the available chlorine content of aqueous waste streams produced in chemical plants, especially calcium hypochlorite plants, in order to permit further purification treatment in waste purification systems which employ activated carbon. The available chlorine content is reduced by chlorinating the impure stream at a temperature in the range from about 80.degree. to 100.degree. C. at a pH in the range from about 5.5 to about 8.5. In order to avoid excessive reactor boilover, close control of these conditions is required. In addition the reaction is time dependent and the holdup time in the reactor and a subsequent hold tank ranges from about 0.5 to about 4 hours. During this reaction the available chlorine forms the corresponding chlorate in the aqueous solution which may be passed through the activated carbon bed without adversely affecting the bed operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.