US4845334A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Plasma furnace inert gas recycling system and process
Assignee: ATI Properties LLC
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Filing: 1988-01-26
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Granted: 1989-07-04
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Expires: 2008-01-26
Abstract
Abstract A system and method for conditioning and recycling inert gases which are used in a plasma furnace. The method comprises the steps of receiving the gas that is output from the plasma furnace and cooling the gas to a desired temperature. Substantially all the dust is removed from the gas and then the gas is compressed to the desired pressure using an oil-flooded screw compressor. Any oil which is introduced by the compressor is removed from the gas and an alarm is provided to signal a high oil level. Substantially all water vapor in the gas is removed and the gas is filtered to remove any remaining dust and small particulates. The amounts of water vapor and oxygen in the gas are monitored. The gas is then recycled to the plasma furnace.
Inventors
- 👤 Stephen C. Stocks
- 👤 Patrick L. Rasmussen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 06:30
CPC Classifications
F; F27; F27D; F27D17/00; F27D17/20; F27D17/22; F27D17/25; B; B01; B01D; B01D46/00; B01D50/00
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
128 words
A system for recycling output gas from a plasma furnace, wherein the gas is typically at relatively high temperatures and relatively low pressures, and wherein the gas is typically contaminated with condensed metal and salt dust, the system comprising: cooling means for lowering the temperature of the gas to a desired temperature; means for receiving gas from the cooling means and removing dust from the gas; compression means for receiving gas from the dust removing means and for compressing the gas to a desired pressure, wherein the compression means comprises an oil-filled screw compressor and wherein the oil in the compressor comprises vacuum pump oil; means for receiving the compressed gas and for removing oil from the gas; and means for removing water vapor from the compressed gas.
Claim 2
Independent Claim
128 words
A system for recycling output gas from a plasma furnace, wherein the gas is typically at relatively high temperatures and relatively low pressures, and wherein the gas is typically contaminated with condensed metal and salt dust, the system comprising: cooling means for lowering the temperature of the gas to a desired temperature; means for receiving gas from the cooling means and removing dust from the gas; compression means for receiving gas from the dust removing means and for compressing the gas to a desired pressure, wherein the compression means comprises an oil-filled screw compressor and wherein the oil in the compressor comprises vacuum pump oil; means for receiving the compressed gas and for removing oil from the gas; and means for removing water vapor from the compressed gas.
Claim 3
Dependent Claim
13 words
The system of claim 1 wherein the cooling means is a heat exchanger.
Claim 4
Dependent Claim
14 words
The system of claim 1 wherein the means for removing dust comprises a cyclone.
Claim 5
Dependent Claim
15 words
The system of claim 1 wherein the means for removing dust comprises a bag house.
Claim 6
Dependent Claim
15 words
The system of claim 1 wherein the means for removing oil comprises an oil separator.
Claim 7
Dependent Claim
22 words
The system of claim 5, and further comprising: alarm means for producing a signal indicative of a failure of the oil separator.
Claim 8
Dependent Claim
15 words
The system of claim 1 wherein the means for removing oil comprises a coalescing filter.
Claim 9
Dependent Claim
15 words
The system of claim 1 wherein the means for removing water vapor is a desiccant.
Claim 10
Dependent Claim
27 words
The system of claim 1 and further comprising: monitoring means for sensing the amount of water vapor in the gas downstream from the water vapor removing means.
Claim 11
Dependent Claim
19 words
The system of claim 1 and further comprising: monitoring means for sensing the amount of oxygen in the gas.
Claim 12
Dependent Claim
11 words
The system of claim 1 wherein the output gas comprises helium.
Claim 13
Dependent Claim
11 words
The system of claim 1 wherein the output gas comprises argon.
Claim 14
Independent Claim
103 words
A method of recycling output gas from a plasma furnace, wherein the gas is typically at relatively high temperatures and relatively low pressures, and wherein the gas is typically contaminated with condensed metal and salt dust, the method comprising the steps of: receiving the gas as it is discharged from the plasma furnace; removing substantially all of the dust from the gas; compressing the gas to a desired pressure using an oil-filled screw compressor wherein the oil comprises vacuum pump oil; removing substantially all oil from the gas; removing substantially all water vapor from the gas; and recycling the gas to the furnace.
Claim 15
Independent Claim
103 words
A method of recycling output gas from a plasma furnace, wherein the gas is typically at relatively high temperatures and relatively low pressures, and wherein the gas is typically contaminated with condensed metal and salt dust, the method comprising the steps of: receiving the gas as it is discharged from the plasma furnace; removing substantially all of the dust from the gas; compressing the gas to a desired pressure using an oil-filled screw compressor wherein the oil comprises vacuum pump oil; removing substantially all oil from the gas; removing substantially all water vapor from the gas; and recycling the gas to the furnace.
Claim 16
Dependent Claim
14 words
The method of claim 13 wherein the gas is compressed to approximately 100 psig.
Claim 17
Dependent Claim
14 words
The method of claim 13 wherein the water vapor is removed using a desiccant.
Claim 18
Dependent Claim
25 words
The method of claim 13 and further comprising the step of: cooling the gas to a desired temperature after it is received from the furnace.
Claim 19
Dependent Claim
15 words
The method of claim 16 wherein the gas is cooled to approximately 200 degrees Farenheit.
Claim 20
Dependent Claim
17 words
The method of claim 13 wherein the oil is removed from the gas using an oil separator.
Claim 21
Dependent Claim
22 words
The method of claim 18 and further comprising the step of: providing an alarm for indicating a failure of the oil separator.
Claim 22
Dependent Claim
23 words
The method of claim 13 and further comprising the step of: filtering the gas after it is compressed to remove any remaining particulates.
Claim 23
Dependent Claim
27 words
The method of claim 13 and further comprising the step of: monitoring the amounts of water vapor and oxygen in the gas recycled back to the furnace.
Claim 24
Independent Claim
144 words
A method of recycling output gas from a plasma furnace, wherein the output gas is typically at relatively high temperatures and relatively low pressures, and wherein the output gas is typically contaminated with condensed metal and salt dust, the method comprising the steps of: receiving the gas discharging from the plasma furnace; cooling the gas to a desired temperature; removing substantially all of the dust from the gas; compressing the gas to a desired pressuring using an oil-filled screw compressor wherein the oil comprises vacuum pump oil; removing substantially all oil from the gas using an oil separator; providing an alarm for indicating a failure of the oil separator; removing substantially all water vapor from the gas; filtering the gas to remove remaining dust and particulates; monitoring the amounts of water vapor and oxygen in the gas; and recycling the gas to the furnace.
Claim 25
Independent Claim
144 words
A method of recycling output gas from a plasma furnace, wherein the output gas is typically at relatively high temperatures and relatively low pressures, and wherein the output gas is typically contaminated with condensed metal and salt dust, the method comprising the steps of: receiving the gas discharging from the plasma furnace; cooling the gas to a desired temperature; removing substantially all of the dust from the gas; compressing the gas to a desired pressuring using an oil-filled screw compressor wherein the oil comprises vacuum pump oil; removing substantially all oil from the gas using an oil separator; providing an alarm for indicating a failure of the oil separator; removing substantially all water vapor from the gas; filtering the gas to remove remaining dust and particulates; monitoring the amounts of water vapor and oxygen in the gas; and recycling the gas to the furnace.
Claim 26
Independent Claim
192 words
A system for conditioning and recycling output gas from a plasma furnace, wherein the gas is typically at relatively high temperature and relatively low pressures, and wherein the gas is typically contaminated with condensed metal and salt dust, the system comprising: a heat exchanger operatively connected to the furnace; a cyclone operatively connected to the heat exchanger; a bag house operatively connected to the cyclone; an inlet receiver operatively connected to the bag house; a first filter connected to an outlet of the inlet receiver; an oil-filled screw compressor operatively connected to the first filter, wherein the compressor contains vacuum pump oil; an oil separator operatively connected to the compressor; a plurality of coalescing filters operatively connected in series to the oil separator; a high oil level indicator and alarm operatively connected to one of the coalescing filters; a discharge receiver operatively connected to the coalescing filters; a desiccant column operatively connected to the discharge receiver; a second filter operatively connected to the desiccant column; and a moisture and oxygen monitor operatively connected to the second filter, wherein the output gas flows through the system and is returned to the plasma furnace.
Claim 27
Independent Claim
192 words
A system for conditioning and recycling output gas from a plasma furnace, wherein the gas is typically at relatively high temperature and relatively low pressures, and wherein the gas is typically contaminated with condensed metal and salt dust, the system comprising: a heat exchanger operatively connected to the furnace; a cyclone operatively connected to the heat exchanger; a bag house operatively connected to the cyclone; an inlet receiver operatively connected to the bag house; a first filter connected to an outlet of the inlet receiver; an oil-filled screw compressor operatively connected to the first filter, wherein the compressor contains vacuum pump oil; an oil separator operatively connected to the compressor; a plurality of coalescing filters operatively connected in series to the oil separator; a high oil level indicator and alarm operatively connected to one of the coalescing filters; a discharge receiver operatively connected to the coalescing filters; a desiccant column operatively connected to the discharge receiver; a second filter operatively connected to the desiccant column; and a moisture and oxygen monitor operatively connected to the second filter, wherein the output gas flows through the system and is returned to the plasma furnace.
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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) | 1992-07-03 | 1993-01-02 | 1993-07-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-07-03 | 1997-01-02 | 1997-07-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-07-03 | 2001-01-02 | 2001-07-04 | $7700.00 | Window Closed / Lapsed |