Sludge thickening method
US7906029B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 25, 2010 |
| Grant date | Mar 15, 2011 |
| Priority date | — |
| Expiry date | Feb 25, 2030 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC02F2209/006
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A differential rate rotary thickener; a power detector which is disposed in a sludge receiver tank for thickened sludge thickened in the differential rate rotary thickener; a discriminator which receives an electric signal for a thickened sludge concentration detected by the power detector and which calculates and discriminate the data; a first controller which receives an instruction signal being a discriminated result in the discriminator and which operates an outer cylinder driving machine and a screw driving machine; a ratio setter which receives a discriminated signal of the discriminator and which increases or decreases a chemical feed rate of flocculant stepwise; and a second controller which receives an instruction signal from the ratio setter and which operates a flocculant-feeding pump are provided. Thickening of sludge is performed by controlling the chemical feed rate, a rotational speed of a screw, and a rotational speed of an outer cylinder screen.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.