Method of removing silicon dioxide from waste liquid, method of cleaning membrane tube and method of processing waste water
US7582212B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 8, 2005 |
| Grant date | Sep 1, 2009 |
| Priority date | — |
| Expiry date | Jun 23, 2027 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T436/206664
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A method of removing silicon dioxide from a waste liquid is described. A solution containing fluoride ions is added into the waste liquid to form a reaction product. A method of cleaning a membrane tube for processing waste water is also described, wherein the membrane tube contains residues of waste water that include a first residue and a second residue containing silicon dioxide. A first cleaning step is conducted to reduce the concentration of the first residue in the membrane tube to a first concentration. A solution containing fluoride ions is added into the tube to react with the second residue to form a reaction product. A second cleaning step is then conducted to reduce the concentration of the residual fluorine ions in the membrane tube to a second concentration.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.