Treatment of solid containing material derived from effluent of wastepaper treating plant
US5846378A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 21, 1997 |
| Grant date | Dec 8, 1998 |
| Priority date | — |
| Expiry date | Mar 21, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S210/928
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A method is described for the treatment of a solid containing material obtained from effluent from an industrial plant or process, eg. a plant for the de-inking of waste paper. Such effluent comprises an aqueous suspension of solids comprising organic material and inorganic particulate material. The inorganic particulate material contains a substantial amount of calcium carbonate and is likely also to contain kaolin or metakaolin. The solids may also contain carbon particles. The method includes subjecting the solid containing material to a heat treatment process such that the temperature is controlled to be maintained in the range 600.degree. C. to 800.degree. C. preferably 600.degree. C. to 750.degree. C., to cause burning of the organic material without decomposition of more than about 50% by weight, preferably not more than about 10% by weight, of the calcium carbonate present to produce a particulate calcium carbonate-containing inorganic material substantially free of organic material. The particulate product is preferably white and useful as a pigment or filler material, eg. in paper making.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.