Filtering system for fine suspensions
Abstract
Abstract A relatively fine mesh flexible filter is placed in a container filled with a suspension of fine solids in a liquid. The liquid is forced through the filter by a relatively low differential pressure, such as an open container and a vacuum source. Before the filter becomes completely clogged by the solids, a small backflow is induced through the filter by reversing the pressure differential across the filter. The reverse flow causes the filter to flex so that the relatively thin layer of material is removed simultaneously. When using a vacuum system, this can be obtained by breaking the vacuum above the container to allow the small hydraulic head to back flush the filter. When the vacuum source is reconnected, the filtering process is resumed. This cycle is repeated until all the liquid has been filtered. In certain applications, the filtrate is the desired product, in others the filter cake, and in still others both the cake and the filtrate are required.
Inventors
- 👤 Noah S Davis
- 👤 John B Cramer
- 👤 Wilbur A Lester
Bibliographic Details
Claims Analysis
Total Claims: 1References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-12-27 | 1975-06-28 | 1975-12-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-27 | 1979-06-28 | 1979-12-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-27 | 1983-06-28 | 1983-12-28 | $7700.00 | Window Closed / Lapsed |