Method for treating residues resulting from the purification of garbage and/or industrial waste incineration fumes
US6403045B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 14, 2000 |
| Grant date | Jun 11, 2002 |
| Priority date | — |
| Expiry date | Mar 14, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02W30/20
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A method for treating residues derived from garbage and/or industrial waste incineration fumes including the steps of desalting the residues by washing with sodium carbonate in sufficient amount or slightly in excess to solubilize all the salts including the sulphates and precipitate the soluble calcium, the pH being higher than 11, then carrying out a solid/liquid separation to obtain a desalinated cake; leaching the desalinated cake with sodium carbonate in sufficient amount or slightly in excess to obtain, by reaction with the lime present in the cake or added thereto if necessary, the alkalinity required for solubilising amphoteric metals, the pH being higher than 12, and obtaining by solid/liquid separation a cake and a supernatant which is neutralised with carbon dioxide, and filtering the recovered solution to obtain metal hydroxide sludge and an aqueous sodium carbonate solution; and neutralising the resulting residues at a pH between 6.5 and 8.5.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.