US4032443A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Removal of grease and oil from particulate bed granules by backwashing with a detergent
Assignee: US Filter Zimpro Inc
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Filing: 1976-01-29
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Granted: 1977-06-28
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Expires: 1996-01-29
Abstract
Abstract Filtering solids from waste water liquids and cleaning, degreasing and restoring the filtering media through the use of cleaning compounds forced up through the filtering substances.
Inventors
- 👤 David S. Ross
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 23:52
CPC Classifications
B; B01; B01D; B01D24/00; B01D24/46; B01D24/4631; B01D24/02; B01D24/20; B01D24/22; B01D17/00; B01D17/08; B01D17/10; B01D2201/00; B01D2201/08; B01D2201/085
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
168 words
Apparatus for the removal of grease and oil film from granular media surfaces in waste water filters comprising a filter, said filter includng a tank having a lower portion, a filter bed of particulate material within said tank above said lower portion, said filter bed having an upper surface, an underdrain structure in the tank adjacent said lower portion and under said bed, an underdrain cavity within said lower portion coextensive with the underdrain structure, means for draining from the underdrain cavity filtered effluent after said filtered effluent has passed through said bed, means for forcing backwashing liquid into the underdrain cavity, means for forcing a predetermined quantity of cleaning solution into the underdrain cavity. means to intermittently energize said liquid forcing means to hydraulically disturb said bed of particulate material in contact with cleaning solution, means to stop said liquid forcing means for a predetermined soak time, and means to initiate a predetermined backwash cycle following a predetermined number of liquid forcing cycles and respective soak periods.
Claim 2
Dependent Claim
168 words
Apparatus for the removal of grease and oil film from granular media surfaces in waste water filters comprising a filter, said filter includng a tank having a lower portion, a filter bed of particulate material within said tank above said lower portion, said filter bed having an upper surface, an underdrain structure in the tank adjacent said lower portion and under said bed, an underdrain cavity within said lower portion coextensive with the underdrain structure, means for draining from the underdrain cavity filtered effluent after said filtered effluent has passed through said bed, means for forcing backwashing liquid into the underdrain cavity, means for forcing a predetermined quantity of cleaning solution into the underdrain cavity. means to intermittently energize said liquid forcing means to hydraulically disturb said bed of particulate material in contact with cleaning solution, means to stop said liquid forcing means for a predetermined soak time, and means to initiate a predetermined backwash cycle following a predetermined number of liquid forcing cycles and respective soak periods.
Claim 3
Dependent Claim
14 words
Apparatus of claim 1 including means providing for trapping air in the underdrain structure.
Claim 4
Dependent Claim
17 words
The apparatus of claim 1 including means to force the cleaning solution in jets into the media.
Claim 5
Dependent Claim
20 words
The apparatus of claim 3 including means to operate the jets into the filter media in alternation with soaking periods.
Claim 6
Dependent Claim
18 words
The apparatus of claim 1 including soaking means to emulsify any tenacious grease film on the media grain.
Claim 7
Dependent Claim
15 words
The apparatus of claim 1 including means for backwashing emulsified grease from the particulate media.
Claim 8
Dependent Claim
16 words
The apparatus of claim 1 including means to apply air under pressure to the under structure.
Claim 9
Dependent Claim
13 words
The apparatus of claim 7 including an external source of air under pressure
Claim 10
Dependent Claim
28 words
The apparatus of claim 1 including means to force the cleaning solution in jets into the filter media, said jets including at least some of the trapped air.
Claim 11
Dependent Claim
20 words
The apparatus of claim 1 including means to compress air against the resistence of the particulate filter from underneath it.
Claim 12
Dependent Claim
26 words
The apparatus of claim 10 including means to apply pressure to the cleaning solution to trap air, the air being forced into the filter media thereby.
Claim 13
Independent Claim
136 words
The method of removing oil and grease film from the granular surfaces of particulate media for filtering waste water in a waste filter wherein a filter bed is provided with an underdrain cavity including the steps of a. forcing a predetermined quantity of a chemical cleaning agent into the underdrain cavity, b. forcing a backwashing liquid into the underdrain cavity and up through the filter bed to substantially inundate the bed, c. stopping the flow of backwashing liquid for a predetermined period, d. hydraulically disturbing said bed of particulate material in contact with said liquid cleaning solution by forcing additional backwashing liquid into said underdrain cavity, e. stopping the flow of backwashing liquid for a predetermined soaking period, f. and initiating a predetermined backwash cycle following a predetermined number of cycles including steps d and e.
Claim 14
Independent Claim
136 words
The method of removing oil and grease film from the granular surfaces of particulate media for filtering waste water in a waste filter wherein a filter bed is provided with an underdrain cavity including the steps of a. forcing a predetermined quantity of a chemical cleaning agent into the underdrain cavity, b. forcing a backwashing liquid into the underdrain cavity and up through the filter bed to substantially inundate the bed, c. stopping the flow of backwashing liquid for a predetermined period, d. hydraulically disturbing said bed of particulate material in contact with said liquid cleaning solution by forcing additional backwashing liquid into said underdrain cavity, e. stopping the flow of backwashing liquid for a predetermined soaking period, f. and initiating a predetermined backwash cycle following a predetermined number of cycles including steps d and e.
Claim 15
Dependent Claim
14 words
The method of claim 12 including providing air under pressure in the underdrain cavity.
Claim 16
Dependent Claim
14 words
The method of claim 13 wherein the air is provided from an external source.
Claim 17
Dependent Claim
17 words
The method of claim 12 including trapping air under the filter bed by means of the cleaner.
Claim 18
Dependent Claim
14 words
The method of claim 12 wherein the cleaner is a solution of sodium hypochlorite.
Claim 19
Dependent Claim
15 words
The method of claim 16 including adding a detergent to the cleaner, up to 10%.
Claim 20
Dependent Claim
14 words
The method of claim 12 including soaking the filtering media with the cleaning admixture.
Claim 21
Dependent Claim
28 words
The method of claim 18 including the step of utilizing variable periods of soaking alternately with periods of forcing the chemical admixture into and through the filter bed.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-06-27 | 1980-12-27 | 1981-06-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-06-27 | 1984-12-27 | 1985-06-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-06-27 | 1988-12-27 | 1989-06-28 | $7700.00 | Window Closed / Lapsed |