Treatment of fluoride-containing wastewater
US11286189B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 30, 2018 |
| Grant date | Mar 29, 2022 |
| Priority date | — |
| Expiry date | Nov 30, 2038 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC02F2103/346
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
The invention relates to a method for treating fluoride-containing, in particular HF containing wastewater to remove fluoride and to a corresponding apparatus. In the new method calcium carbonate is reacted in a reaction step at an acidic pH≤4 with the fluoride in the wastewater to form calcium fluoride particles. Then, in a subsequent filtration step said calcium fluoride particles are separated by a porous membrane from the treated wastewater. The inventive apparatus comprises at least one reaction container/tank for reacting calcium carbonate at an acidic pH≤4 with fluoride in the wastewater to form calcium fluoride particles, as well as at least one porous membrane, in particular at least one porous ceramic membrane for separating calcium fluoride particles from the treated wastewater in a filtration step.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.