US3831755A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Filtration apparatus
Assignee: Smith and Loveless Inc
•
Filing: 1971-06-28
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Granted: 1974-08-27
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Expires: 1991-06-28
Abstract
Abstract An improved apparatus for the cleaning of filter beds of a filtration apparatus which comprises a plurality of filter units, each of the units having an upper influent zone, a filter bed, and a lower filtrate zone, and including means for pumping liquid from all of the filtrate zones at a given pumping rate. In accordance with the invention, during the service cycle, liquid is pumped by the pump means from the filtrate zones to service, so that it passes through the filter bed in a downflow direction. When one of the filter units requires backwashing, the pump means is employed to pump liquid simultaneously from the filtrate zones of a majority of the filter units, so that the backwash rate is greater than the normal downflow rate through the filter unit. As an alternative to backwashing a minority of the filter unit with liquid from the majority of the units, or in addition thereto, the increased backwashing rate can be provided by increasing the pumping rate beyond the given rate during the backwashing by using booster pump means.
Inventors
- 👤 B Goodman
- 👤 F Weis
- 👤 K Mikkelson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 22:06
CPC Classifications
B; B01; B01D; B01D35/00; B01D35/12; B01D24/00; B01D24/02; B01D24/10; B01D24/12; B01D24/46; B01D24/4631; B01D24/48; B01D24/4869
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
231 words
Improved apparatus for the filtration of liquids comprising: a plurality of filter units, each of said units comprising an upper influent zone, a filter bed, and a lower filtrate zone; means for delivering liquid to said influent zones; means including pump means operatively connected for pumping liquid from all of said filtrate zones to service at a given pumping rate; means for delivering liquid from the filtrate zones of a majority of said filter units through said pump means to the filtrate zones of a minority of said filter units, whereby to backwash the filter beds of said minority of said filter units with liquid delivered simultaneously from said majority of said filter units; means including booster pump means operatively connected to pump additional liquid from said filtrate zones of said majority of said filter units to said filtrate zones of said minority of said filter units and to provide auxiliary pumping of liquid through all of said filter beds to service; and level sensor means in said influent zones, said level sensor means being operatively connected to said booster pump means when said liquid is being delivered to service to start said booster pump means when the liquid level in one of said influent zones rises above a given high level and to stop said booster pump means when said liquid in said influent zone falls below a given level.
Claim 2
Dependent Claim
231 words
Improved apparatus for the filtration of liquids comprising: a plurality of filter units, each of said units comprising an upper influent zone, a filter bed, and a lower filtrate zone; means for delivering liquid to said influent zones; means including pump means operatively connected for pumping liquid from all of said filtrate zones to service at a given pumping rate; means for delivering liquid from the filtrate zones of a majority of said filter units through said pump means to the filtrate zones of a minority of said filter units, whereby to backwash the filter beds of said minority of said filter units with liquid delivered simultaneously from said majority of said filter units; means including booster pump means operatively connected to pump additional liquid from said filtrate zones of said majority of said filter units to said filtrate zones of said minority of said filter units and to provide auxiliary pumping of liquid through all of said filter beds to service; and level sensor means in said influent zones, said level sensor means being operatively connected to said booster pump means when said liquid is being delivered to service to start said booster pump means when the liquid level in one of said influent zones rises above a given high level and to stop said booster pump means when said liquid in said influent zone falls below a given level.
Claim 3
Dependent Claim
19 words
The apparatus as defined in claim 1 further comprising means for delivering gas under pressure to said filtrate zones.
Claim 4
Dependent Claim
236 words
Improved apparatus for the filtration of liquids comprising: a plurality of filter units, each of said units comprising an upper influent zone, a filter bed, and a lower filtrate zone; means for delivering liquid to said influent zones; means including pump means for pumping liquid to service from all of said filtrate zones at a given pumping rate; means for delivering liquid from the filtrate zones of a first portion of said filter units through said pump means to the filtrate zones of a second portion of said filter units whereby to backwash the filter beds of said second portion of said filter units with filtEred liquid delivered simultaneously from said first portion of said filter units; means including booster pump means operatively connected to pump additional liquid from said filtrate zones of said first portion of said filter units to said filtrate zones of said second portion of said filter units and to provide auxiliary pumping of liquids through all of said filter beds to service; and level sensor means in said influent zones, said level sensor means being operatively connected to said booster pump means when said liquid is being delivered to service to start said booster pump means when the liquid level in one of said influent zones rises above a given high level and to stop said booster pump means when said liquid in said influent zone falls below a given level.
Claim 5
Dependent Claim
236 words
Improved apparatus for the filtration of liquids comprising: a plurality of filter units, each of said units comprising an upper influent zone, a filter bed, and a lower filtrate zone; means for delivering liquid to said influent zones; means including pump means for pumping liquid to service from all of said filtrate zones at a given pumping rate; means for delivering liquid from the filtrate zones of a first portion of said filter units through said pump means to the filtrate zones of a second portion of said filter units whereby to backwash the filter beds of said second portion of said filter units with filtEred liquid delivered simultaneously from said first portion of said filter units; means including booster pump means operatively connected to pump additional liquid from said filtrate zones of said first portion of said filter units to said filtrate zones of said second portion of said filter units and to provide auxiliary pumping of liquids through all of said filter beds to service; and level sensor means in said influent zones, said level sensor means being operatively connected to said booster pump means when said liquid is being delivered to service to start said booster pump means when the liquid level in one of said influent zones rises above a given high level and to stop said booster pump means when said liquid in said influent zone falls below a given level.
Claim 6
Dependent Claim
18 words
The apparatus as defined in claim 3 wherein said plurality of filter units consists of two filter units.
Claim 7
Dependent Claim
19 words
The apparatus as defined in claim 3 wherein said plurality of filter units comprises at least three filter units.
Claim 8
Dependent Claim
19 words
The apparatus as defined in claim 3 further comprising means for delivering air under pressure to said filtrate zones.
Claim 9
Dependent Claim
222 words
Improved apparatus for the filtration of liquids comprising: three filter units, each of said units comprising an upper influent zone, a filter bed, and a lower filtrate zone; means for delivering liquid to said influent zones; means including pump means for pumping liquid to service from all of said filtrate zones at a given pumping rate; means for delivering liquid from the filtrate zones of any two of said filter units through said pump means to the filtrate zone of the remaining filter unit; means including booster pump means operatively connected to pump additional liquid from said filtrate zones of said two of said filter units to said filtrate zone of said remaining filter unit, whereby to backwash the filter bed of said remaining filter unit with filtered liquid delivered simultaneously from said two of said filter units and to provide auxiliary pumping of liquid through all of said filter beds to service; and level sensor means in said influent zones, said level sensor means being operatively connected to said booster pump means when said liquid is being delivered to service to start said booster pump means when the liquid level in one of said influent zones rises above a given high level and to stop said booster pump means when said liquid in said influent zone falls below a given level.
Claim 10
Dependent Claim
222 words
Improved apparatus for the filtration of liquids comprising: three filter units, each of said units comprising an upper influent zone, a filter bed, and a lower filtrate zone; means for delivering liquid to said influent zones; means including pump means for pumping liquid to service from all of said filtrate zones at a given pumping rate; means for delivering liquid from the filtrate zones of any two of said filter units through said pump means to the filtrate zone of the remaining filter unit; means including booster pump means operatively connected to pump additional liquid from said filtrate zones of said two of said filter units to said filtrate zone of said remaining filter unit, whereby to backwash the filter bed of said remaining filter unit with filtered liquid delivered simultaneously from said two of said filter units and to provide auxiliary pumping of liquid through all of said filter beds to service; and level sensor means in said influent zones, said level sensor means being operatively connected to said booster pump means when said liquid is being delivered to service to start said booster pump means when the liquid level in one of said influent zones rises above a given high level and to stop said booster pump means when said liquid in said influent zone falls below a given level.
Claim 11
Dependent Claim
19 words
The apparatus as defined in claim 7 further comprising means for delivering air under pressure to said filtrate zones.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-08-26 | 1978-02-25 | 1978-08-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-08-26 | 1982-02-25 | 1982-08-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-08-26 | 1986-02-25 | 1986-08-27 | $7700.00 | Window Closed / Lapsed |