Effective diffuser/thickener screen backflushing
US4793161A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 27, 1987 |
| Grant date | Dec 27, 1988 |
| Priority date | — |
| Expiry date | Nov 27, 2007 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01D33/763
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
The screens of a pulp treating vessel, such as a paper pulp thickener, or diffuser, are back flushed in a simple yet effective manner. The screens are mounted to a supporting conduit within a vertical vessel, and a cylinder is connected at one open end to the conduit, and the other open end is disposed within the pulp inside the vessel. A piston is mounted within the cylinder and relative movement between the piston and cylinder is effected periodically in order to force liquid from within the cylinder into the conduit and out the screens, backflushing the screens and preventing clogging. Since no additional volume of liquid is added to the vessel during backflushing, no surge occurs in the vessel. Conventional accumulators, on/off valves, and the like can be eliminated while--in the case of diffusion washing--efficiency can be increased as much as 20-30%, and capacity increased as much as about 15%.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.