Method of producing recycled hardened materials using waste gypsum
US7731792B2 · kind B2 · utility
1Cited by
4References
8Claims
0Family size
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Key dates
| Filing date | Jul 7, 2005 |
| Grant date | Jun 8, 2010 |
| Priority date | — |
| Expiry date | Apr 16, 2026 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02W30/91
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Disclosed herein is a method for producing a recycled hardened material using waste gypsum. The method comprises treating acidic wastewater generated in the production of copper, zinc or titanium or the production of sodium hydroxide (caustic soda) and chlorine using saline water, with calcium hydroxide (slaked lime), so as to precipitate sludge, and mixing the precipitated sludge with pulp sludge ashes having pozzolanic properties.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.