US3813892A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Water purification system
Assignee: Avco Corp
•
Filing: 1971-08-23
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Granted: 1974-06-04
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Expires: 1991-08-23
Abstract
Abstract A water purification system useful, for example, in the desalination of saline water, which system uses means for crystallizing the water in such saline solution through the use of an appropriate refrigerant to form a slurry of ice crystals and brine which is fed to a wash column for separating the brine from the ice crystals. The ice crystals form a porous ice bed for movement through the column, such bed being washed by a wash liquid flowing in direction counter to the ice bed movement. Ice is removed at one end of the column and brine and wash water is removed through an intermediate permeable port of the column, the ice preferably being melted by indirect heat exchange with vaporized refrigerant. The pressure relationships at the input end of the ice bed, at the intermediate permeable port, and at the output end of the ice bed are controlled independently of the pressures at the crystallizer and at the melter units of the system, such pressures being capable of adjustment in accordance with the size of the ice crystals formed in the crystallizer (and, hence, the permeability of the porous ice bed formed in the wash column) to provide for maximum ice output from the column and minimization of wash liquid loss therein.
Inventors
- 👤 W Johnson
- 👤 J Fraser
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 01:19
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/22; B; B01; B01D; B01D9/00; B01D9/0004; B01D9/004; B01D9/0045; B01D9/0059; B01D9/0063; C02F2103/00; C02F2103/08; Y; Y02; Y02A; Y02A20/00; Y02A20/124
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
26 words
A process as in claim 1 wherein said liquid is contaminated water; said solid crystals are ice crystals; and said processed liquid output is purified water.
Claim 2
Dependent Claim
24 words
A process as in claim 2 wherein said contaminated water is a saline solution; and said concentrated solution of said contaminated water is brine.
Claim 3
Dependent Claim
46 words
A process as in claim 2 wherein said liquid refrigerant directly contacts said contaminated water in said crystallization zone and further comprising the step of cooling said decontaminated water to a temperature just above freezing before the refrigerant is evaporated in said direct contact with it.
Claim 4
Dependent Claim
51 words
A process as in claim 1 wherein said output end of said wash zone and said liquefying zone form part of a substantially closed circulatory system to maintain the pressure within the circulatory system substantially constant and said substantial portion of said processed liquid is circulated through said closed circulatory system.
Claim 5
Dependent Claim
118 words
A process as in claim 1 plus the additional step of adjusting the pressure relationships among the pressures P1, P2, and P3 at the input end of said porous bed, at said intermediate point, and at the output end of said porous bed, respectively, independently of the pressureS in said crystallization zone and said liquefying zone, to move said porous bed through said wash zone at a selected rate so as to maximize the rate of extraction of said solid crystals from said zone in accordance with said selected range of sizes of said solid crystals produced by said first heat exchange relationship and so as to minimize the loss of said wash liquid from said wash zone.
Claim 6
Dependent Claim
41 words
A process as in claim 2 and further comprising the step of: passing the liquid refrigerant formed after said heat exchange relationship with said extracted ice crystals to said crystallization zone for said first heat exchange relationship with said contaminated water.
Claim 7
Dependent Claim
104 words
A process as in claim 7 wherein said refrigerant vapor is partially condensed by said indirect heat exchange relationship with said extracted ice crystals and wherein said process further comprises the steps of: pressurizing the refrigerant vapor remaining after the indirect heat exchange relationship with said extracted ice crystals; passing said pressurized remaining refrigerant vapor through a first refrigerant vapor condensing zone in indirect heat exchange relationship with a coolant to at least in part condense said pressurized remaining vapor to a liquid form; and passing said remaining liquid refrigerant to said crystallization zone for said first heat exchange relationship with said contaminated water.
Claim 8
Dependent Claim
38 words
A process as in claim 8 and further including the step of venting to the atmosphere vapors, other than refrigerant vapor, that are present after said indirect heat exchange between said vaporized refrigerant and said extracted ice crystals.
Claim 9
Dependent Claim
107 words
A process as in claim 9 wherein said venting step further includes the steps of extracting from said first refrigerant vapor condensing zone substantially all vapors contained therein including any refrigerant vapor that is not condensed to a liquid in said first refrigerant vapor condensing zone; pressurizing said vapors extracted from said first refrigerant vapor condensing zone; passing said extracted pressurized vapors to a second refrigerant vapor condensing zone in indirect heat exchange relationship with a further coolant to condense said previously uncondensed refrigerant vapor; passing said pressurized vapors, other than said refrigerant vapor, to the atmosphere; and passing said condensed refrigerant vapor to said crystallization zone.
Claim 10
Dependent Claim
73 words
A process as in claim 8 further comprising the steps of exposing said concentrated solution extracted from said wash zone to a low pressure region whereby refrigerant in said concentrated solution is evaporated into a vapor form; extracting said refrigerant vapor from said low pressure region; and pressurizing said extracted vapor and introducing said pressurized vapor into said first refrigerant vapor condensing zone and mixing it therein with said pressurized remaining refrigerant vapor.
Claim 11
Dependent Claim
67 words
A process as in claim 2 and further comprising the steps of controlling the rate of removal of said slurry from said crystallization zone so as to maintain the sizes of said ice crystals therein within a selected range; and adjusting the relationships among said pressures P1, P2 and P3 so as to maintain said selected rate of movement of said ice bed through said wash zone.
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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) | 1977-06-03 | 1977-12-03 | 1978-06-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-03 | 1981-12-03 | 1982-06-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-03 | 1985-12-03 | 1986-06-04 | $7700.00 | Window Closed / Lapsed |