US3928158A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrofilter
Assignee: General Atomics Corp
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Filing: 1974-08-26
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Granted: 1975-12-23
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Expires: 1994-08-26
Abstract
Abstract A method and apparatus for removing electrically conductive suspended contaminants from high resistivity oils free of significant amounts of dispersed water by flowing the oil through the interstitial spaces defined within a mass of substantially spherical ceramic beads of high electrical resistivity and wherein a high gradient electrostatic field is maintained across the mass.
Inventors
- 👤 G Ray Fritsche
- 👤 Leonard W Haniak
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 12:13
CPC Classifications
B; B01; B01D; B01D35/00; B01D35/06; B03; B03C; B03C5/00; B03C5/02; B03C5/022; B03C5/024; C; C10; C10G; C10G32/00; C10G32/02
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
101 words
A METHOD FOR REMOVING FINLY DIVIDED SUSPENDED SOLID CONTAMINANTS INCLUDING ELECTRICALLY CONDUCTIVE SOLIDS FROM OILS HAVING A HIGH RESISTIVITY AND FREE OF SIGNIFICANT AMOUNTS OF DISPERSED WATER WHICH COMPRISES FLOWING THE OIL SUBSTANTIALLY DOWNWARDLY THROUGH INTERSTITIAL SPACES WITHIN A PARTICULATE BED OF SUBSTANTIALLY SPHERICAL NONPOROUS AND NONDEFORMABLE CERAMIC BEADS OF HIGH ELECTRICAL RESISTIVITY HAVING A SMOOTH OUTER SURFACE AND DIAMETERS IN THE RANGE OF ABOUT 1/32 INCH TO ABOUT 1/4 INCH, AND MAINTAINING AN ELECTROSTATIC FIELD HAVING A VOLTAGE GRADIENT OF AT LEAST ABOUT 5 KV PER INCH SUBSTANTIALLY HORIZNTALLY ACROSS SAID BED DURING THE THE DOWNWARD FLOW OF THE OIL.
Claim 2
Independent Claim
101 words
A METHOD FOR REMOVING FINLY DIVIDED SUSPENDED SOLID CONTAMINANTS INCLUDING ELECTRICALLY CONDUCTIVE SOLIDS FROM OILS HAVING A HIGH RESISTIVITY AND FREE OF SIGNIFICANT AMOUNTS OF DISPERSED WATER WHICH COMPRISES FLOWING THE OIL SUBSTANTIALLY DOWNWARDLY THROUGH INTERSTITIAL SPACES WITHIN A PARTICULATE BED OF SUBSTANTIALLY SPHERICAL NONPOROUS AND NONDEFORMABLE CERAMIC BEADS OF HIGH ELECTRICAL RESISTIVITY HAVING A SMOOTH OUTER SURFACE AND DIAMETERS IN THE RANGE OF ABOUT 1/32 INCH TO ABOUT 1/4 INCH, AND MAINTAINING AN ELECTROSTATIC FIELD HAVING A VOLTAGE GRADIENT OF AT LEAST ABOUT 5 KV PER INCH SUBSTANTIALLY HORIZNTALLY ACROSS SAID BED DURING THE THE DOWNWARD FLOW OF THE OIL.
Claim 3
Dependent Claim
23 words
A method as set forth in claim 1 in which the beads have a resistivity of at least about 1 X 108 ohm-cm.
Claim 4
Dependent Claim
15 words
A method as set forth in claim 1 in which the beads are glass beads.
Claim 5
Dependent Claim
23 words
A method as set forth in claim 1 in which the resistivity of the beads is higher than the resistivity of the oil.
Claim 6
Independent Claim
123 words
A method for removing finely divided electrically conductive solid particles from an oil having high resistivity and free of significant amounts of dispersed water which comprises alternately flowing oil downwardly through a particulate bed of nonporous, nondeformable, substantially spherical ceramic beads having a smooth outer surface and diameters in the range of 1/32 inch to 1/4 inch between laterally spaced-apart electrodes while maintaining a substantially horizontal voltage gradient of at least about 5 kilovolts per inch between said electrodes, and backflushing a nonaqueous liquid upwardly through the bed at a rate causing expansion of the bed and movement of the beads relative to one another while the voltage gradient is interrupted to remove from the bed solid particles deposited on the glass beads.
Claim 7
Independent Claim
123 words
A method for removing finely divided electrically conductive solid particles from an oil having high resistivity and free of significant amounts of dispersed water which comprises alternately flowing oil downwardly through a particulate bed of nonporous, nondeformable, substantially spherical ceramic beads having a smooth outer surface and diameters in the range of 1/32 inch to 1/4 inch between laterally spaced-apart electrodes while maintaining a substantially horizontal voltage gradient of at least about 5 kilovolts per inch between said electrodes, and backflushing a nonaqueous liquid upwardly through the bed at a rate causing expansion of the bed and movement of the beads relative to one another while the voltage gradient is interrupted to remove from the bed solid particles deposited on the glass beads.
Claim 8
Dependent Claim
27 words
A method as set forth in claim 1 in which the beads have a smooth outer surface and a Krumbein roundness and sphericity of at least 0.9.
Claim 9
Dependent Claim
15 words
A method as set forth in claim 1 in which the electrostatic gradient is unidirectional.
Claim 10
Dependent Claim
17 words
A method as set forth in claim 1 in which the direction of the electrostatic gradient alternates.
Claim 11
Dependent Claim
35 words
A method as set forth in claim 1 in which the rate of flow of the oil through the bed of beads provides a time in the bed of beads of at least 15 seconds.
Claim 12
Dependent Claim
33 words
A method as set forth in claim 1 in which the temperature of the oil flowing through the bed of beads is in the range of -100* F. to several hundred degrees Fahrenheit.
Claim 13
Independent Claim
169 words
A system for removing finely divided electrically conductive suspended solid contaminants from high resistivity oils comprising a casing having an inlet and an outlet, a particulate bed of substantially spherical nonporous and nondeformable ceramic beads having a high resistivity, diameters in the range of 1/32 inch to about 1/4 inch and a smooth surface supported in the casing, laterally spaced-apart electrodes engaging said particulate bed, means for flowing the high-resistivity oil from the inlet through the particulate bed between the electrodes to the outlet, means for maintaining a voltage gradient of at least about 5 kilovolts per inch between the electrodes, means for flowing a nonaqueous liquid upwardly through the filter at a rate causing expansion of the bed and movement of the beads relative to one another to remove precipitated solids from the bed, and means for alternating flow of the high-resistivity oil through the bed and flow of the nonaqueous liquid upwardly through the bed and for interrupting the voltage gradient during the period of upward flow.
Claim 14
Independent Claim
169 words
A system for removing finely divided electrically conductive suspended solid contaminants from high resistivity oils comprising a casing having an inlet and an outlet, a particulate bed of substantially spherical nonporous and nondeformable ceramic beads having a high resistivity, diameters in the range of 1/32 inch to about 1/4 inch and a smooth surface supported in the casing, laterally spaced-apart electrodes engaging said particulate bed, means for flowing the high-resistivity oil from the inlet through the particulate bed between the electrodes to the outlet, means for maintaining a voltage gradient of at least about 5 kilovolts per inch between the electrodes, means for flowing a nonaqueous liquid upwardly through the filter at a rate causing expansion of the bed and movement of the beads relative to one another to remove precipitated solids from the bed, and means for alternating flow of the high-resistivity oil through the bed and flow of the nonaqueous liquid upwardly through the bed and for interrupting the voltage gradient during the period of upward flow.
Claim 15
Dependent Claim
35 words
A system as set forth in claim 11 in which the means for flowing the oil through the bed of beads directs the oil downwardly through the bed and the electrodes are spaced horizontally apart.
Claim 16
Dependent Claim
14 words
A system as set forth in claim 12 in which the beads are glass.
Claim 17
Dependent Claim
117 words
A filter for removing finely divided electrically conductive suspended solid contaminants from high-resistivity oils comprising a vertical cylindrical casing of an electrically conductive material, a particulate bed of substantially spherical nonporous and nondeformable ceramic beads of high resistivity having a smooth outer surface and a maximum diameter of 1/4 inch within the casing, inlet means for delivering the oil to be filtered into the casing above the bed, an outlet at the lower end of the casing for discharging filtered oil from the filter, a centrally located electrode extending vertically through the bed of beads, and means for maintaining a voltage gradient of at least about 5 KV per inch between the electrode and the cylindrical casing.
Claim 18
Dependent Claim
117 words
A filter for removing finely divided electrically conductive suspended solid contaminants from high-resistivity oils comprising a vertical cylindrical casing of an electrically conductive material, a particulate bed of substantially spherical nonporous and nondeformable ceramic beads of high resistivity having a smooth outer surface and a maximum diameter of 1/4 inch within the casing, inlet means for delivering the oil to be filtered into the casing above the bed, an outlet at the lower end of the casing for discharging filtered oil from the filter, a centrally located electrode extending vertically through the bed of beads, and means for maintaining a voltage gradient of at least about 5 KV per inch between the electrode and the cylindrical casing.
Claim 19
Dependent Claim
14 words
A filter as set forth in claim 14 in which the beads are glass.
Claim 20
Dependent Claim
16 words
A method as set forth in claim 5 in which the ceraMic beads are glass beads.
Claim 21
Dependent Claim
27 words
A method as set forth in claim 5 in which the ceramic beads are glass beads having a resistivity of at least about 1 X 108 ohm-cm.
Claim 22
Dependent Claim
23 words
A system as set forth in claim 13 in which the glass beads have a resistivity of at least 1 X 108 ohm-cm.
Claim 23
Dependent Claim
15 words
A filter as set forth in claim 14 in which the beads are soda-lime glass.
Claim 24
Dependent Claim
34 words
A filter as set forth in claim 15 in which the glass beads comprise a mixture of beads having a resistivity ranging from approximately 1 X 109 ohm-cm to approximately 2 X 1014 ohm-cm.
Claim 25
Dependent Claim
109 words
A filter for removing finely divided electrically conductive solid particles from high-resistivity liquids comprising a cylindrical casing having an inlet and an outlet, a particulate bed of substantially nonporous and nondeformable spherical ceramic beads of high electrical resistivity having a smooth outer surface and a maximum diameter of 1/4 inch within the casing between the inlet and outlet thereof, a first electrode centrally located and extending vertically downwardly into engagement with the particulate bed, a second electrode laterally spaced from and surrounding the first electrode and engaging the particulate bed, and means for maintaining a voltage gradient of at least about 5 KV per inch between the two electrodes.
Claim 26
Dependent Claim
109 words
A filter for removing finely divided electrically conductive solid particles from high-resistivity liquids comprising a cylindrical casing having an inlet and an outlet, a particulate bed of substantially nonporous and nondeformable spherical ceramic beads of high electrical resistivity having a smooth outer surface and a maximum diameter of 1/4 inch within the casing between the inlet and outlet thereof, a first electrode centrally located and extending vertically downwardly into engagement with the particulate bed, a second electrode laterally spaced from and surrounding the first electrode and engaging the particulate bed, and means for maintaining a voltage gradient of at least about 5 KV per inch between the two electrodes.
Claim 27
Independent Claim
171 words
A method for removing finely divided solid particles having a diameter less than 5 microns from a liquid having a high resistivity and free of significant amounts of dispersed water which comprises flowing the liquid in a direction other than upwardly through a particulate bed of nonporous, nondeformable ceramic beads having a high resistivity, a smooth outer surface and diameters in the range of about 1/32 inch to about 1/4 inch between spaced-apart electrodes in contact with the particulate bed, maintaining a voltage gradient of at least about 5 KV per inch between said electrodes during the flow of the liquid of high resistivity, periodically interrupting the voltage gradient between the electrodes and the flow of liquid through the particulate bed, and while the flow of liquid of high resistivity and the voltage gradient are interrupted flowing a nonaqueous backflushing liquid upwardly through the particulate bed at a rate causing expansion of the particulate bed and movement of the beads relative to one another to remove solids deposited on the beads.
Claim 28
Independent Claim
171 words
A method for removing finely divided solid particles having a diameter less than 5 microns from a liquid having a high resistivity and free of significant amounts of dispersed water which comprises flowing the liquid in a direction other than upwardly through a particulate bed of nonporous, nondeformable ceramic beads having a high resistivity, a smooth outer surface and diameters in the range of about 1/32 inch to about 1/4 inch between spaced-apart electrodes in contact with the particulate bed, maintaining a voltage gradient of at least about 5 KV per inch between said electrodes during the flow of the liquid of high resistivity, periodically interrupting the voltage gradient between the electrodes and the flow of liquid through the particulate bed, and while the flow of liquid of high resistivity and the voltage gradient are interrupted flowing a nonaqueous backflushing liquid upwardly through the particulate bed at a rate causing expansion of the particulate bed and movement of the beads relative to one another to remove solids deposited on the beads.
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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) | 1978-12-22 | 1979-06-23 | 1979-12-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-22 | 1983-06-23 | 1983-12-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-22 | 1987-06-23 | 1987-12-23 | $7700.00 | Window Closed / Lapsed |