Process for using sludge from geothermal brine to make concrete and concrete composition
US4761182A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 8, 1987 |
| Grant date | Aug 2, 1988 |
| Priority date | — |
| Expiry date | Apr 8, 2007 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S588/901
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A process is provided for using silicious sludge (filter cake), obtained by precipitation of silica from silica-rich geothermal brine, to make a concrete material (geocrete). The process includes combining the sludge with a cementing material, such as portland cement and/or flyash and activating the cementing material with an activating media. When portland cement is used as the cementing material, the activating media is water. In such case, the sludge is preferably dewatered and the residual water content is determined, the entrapped brine adding to the water content of the mixture. Preferably, the dry weight ratio of sludge to cementing material is about 2:1 to about 3:1; although, ratios as high as 9:1 can be used when high strength of the geocrete is not required. The preferred amount of water used is about 40 weight percent, including water content of the sludge, which may typically be between about 10 and about 30 weight percent. The sludge may contain hazardous or toxic materials which precipitate from the brine with the silica and which are present in the entrapped brine; therefore, the sludge may be water washed before use to flush out residual brine and some contaminants…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.