Method and system for treating drinking water
US5314629A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 6, 1992 |
| Grant date | May 24, 1994 |
| Priority date | — |
| Expiry date | Nov 6, 2012 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC02F2303/185
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
The present invention provides a new and improved method for treating drinking water in a drinking water treatment plant that provides for substantial or complete removal of chlorine dioxide and an associated by-product from water when chlorine dioxide is used as an initial disinfectant and/or chemical oxidizing agent. More particularly, the present invention provides a means for decreasing undesirable residual amounts of chlorine dioxide and chlorite ion using ferrous chloride. The novel process includes the addition of chlorine dioxide for disinfection/oxidation of the process water, a first sedimentation basin for processing the water and/or providing adequate chlorine dioxide contact time, the addition of ferrous chloride for treating the water and removing residual amounts of chlorine dioxide and chlorite ion, a source of chlorine (or alternative oxidizing agent) to precipitate residual ferrous iron, a second sedimentation basin, or similar settling mechanism, for processing the water after it has been mixed and reacted with the ferrous chloride and the oxidizing agent, and a filter for processing the water following the second sedimentation basin.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.