US4783261A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rigid filter plate and method for producing same
Assignee: Individual
•
Filing: 1987-07-24
•
Granted: 1988-11-08
•
Expires: 2007-07-24
Abstract
Abstract An improved rigid filter plate for use in sludge dewatering or oil and water separation is characterized by a lower layer of relatively large material and an upper layer of relatively smaller material bonded thereto, with grains of sand interspersed within the upper layer and bonded to the material making up the upper layer. The device yields high efficacy in sludge dewatering and oil and water separation, while requiring a low level of cleaning and maintenance, yet is resistant to damage from mechanical cleaning when cleaning is necessary. An efficient and economical method of producing the device is also disclosed herein.
Inventors
- 👤 E. Arnold Lingle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 06:24
CPC Classifications
B; B01; B01D; B01D17/00; B01D17/08; B01D17/10; B01D39/00; B01D39/14; B01D39/20; B01D39/2068; B01D39/2072; B01D39/2079
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
85 words
A rigid sludge or oil separation filter plate, comprising: (a) an upper layer of silica of 1/8 to 1/4 inches in size bonded together by adhesive means, and having a smaller amount by volume of sand having grains of a size of 1/400 inches to 1/12 inches homogenously interspersed therein, and bonded to said silica by said adhesive means; and (b) a lower layer of stone of a size which is larger than that of said silica, with said stone bonded together by adhesive means.
Claim 2
Dependent Claim
85 words
A rigid sludge or oil separation filter plate, comprising: (a) an upper layer of silica of 1/8 to 1/4 inches in size bonded together by adhesive means, and having a smaller amount by volume of sand having grains of a size of 1/400 inches to 1/12 inches homogenously interspersed therein, and bonded to said silica by said adhesive means; and (b) a lower layer of stone of a size which is larger than that of said silica, with said stone bonded together by adhesive means.
Claim 3
Dependent Claim
23 words
A rigid sludge or oil separation filter plate, as described in claim 1, wherein said stone is 1/2 to 11/2 inches in size.
Claim 4
Dependent Claim
31 words
A rigid sludge or oil separation filter plate, as described in claim 1, wherein the ratio of sand to silica by volume is approximately 1 part sand to 20 parts silica.
Claim 5
Dependent Claim
31 words
A rigid sludge or oil separation filter plate, as described in claim 2, wherein the ratio of sand to silica by volume is approximately 1 part sand to 20 parts silica.
Claim 6
Dependent Claim
73 words
A method of resurfacing a rigid sludge or oil separation filter plate of the type described in claim 1, comprising the steps of: (a) producing a resurfacing mixture by homogenously mixing silica of a size of 1/8 inch to 1/4 inch, sand having grains of 1/400 inches to 1/12 inches in size and adhesive; (b) applying said resurfacing mixture to a top surface of the filter plate; and (c) leveling said resurfacing mixture.
Claim 7
Dependent Claim
73 words
A method of resurfacing a rigid sludge or oil separation filter plate of the type described in claim 2, comprising the steps of: (a) producing a resurfacing mixture by homogenously mixing silica of a size of 1/8 inch to 1/4 inch, sand having grains of 1/400 inches to 1/12 inches in size and adhesive; (b) applying said resurfacing mixture to a top surface of the filter plate; and (c) leveling said resurfacing mixture.
Claim 8
Dependent Claim
73 words
A method of resurfacing a rigid sludge or oil separation filter plate of the type described in claim 3, comprising the steps of: (a) producing a resurfacing mixture by homogenously mixing silica of a size of 1/8 inch to 1/4 inch, sand having grains of 1/400 inches to 1/12 inches in size and adhesive; (b) applying siad resurfacing mixture to a top surface of the filter plate; and (c) leveling said resurfacing mixture.
Claim 9
Dependent Claim
73 words
A method of resurfacing a rigid sludge or oil separation filter plate of the type described in claim 4, comprising the steps of: (a) producing a resurfacing mixture by homogenously mixing silica of a size of 1/8 inch to 1/4 inch, sand having grains of 1/400 inches to 1/12 inches in size and adhesive; (b) applying said resurfacing mixture to a top surface of the filter plate; and (c) leveling said resurfacing mixture.
References Cited (Backward Citations)
US2732078A
Cited
US3292788A
Cited
US4186100A
Cited
US4340478A
Cited
US4381998A
Cited
US4452698A
Cited
US4661258A
Cited
US4441997A
Cited
US4564450A
Cited
US4689150A
Cited
US4692248A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-11-08 | 1992-05-09 | 1992-11-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-11-08 | 1996-05-09 | 1996-11-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-11-08 | 2000-05-09 | 2000-11-08 | $7700.00 | Window Closed / Lapsed |