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US5142873A Expired / Lapsed US ⏱️ 0.0 years remaining

Vapor control system for vapor degreasing/defluxing equipment

Assignee: EIDP Inc
•
Filing: 1991-06-10
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Granted: 1992-09-01
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Expires: 2011-06-10
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Abstract

Abstract An improved vapor degreaser characterized by a deep freeboard zone (i.e., freeboard to width ratio of 1.0 to 2.3) containing a three-stage condenser/heat exchanger configuration comprising: a water-cooled lower primary exchanger operating above 32° F. to effect condensation of the bulk of the vapor generated by the boiling sump and a combination of an intermediate exchanger above, but preferably overlapping, the primary exchanger and a dehumidifying third exchanger position just below the top lip of the degreaser, both operating at a temperature below 32° F. (preferably +10° to -30° F.) to effect a reduction in the vapor concentration gradient that controls the rate of vapor diffusion through the freeboard zone. The improved vapor degreaser is particularly useful in reducing vapor losses when using low boiling solvents.

Inventors

  • 👤 Robert B. Ramsey, Jr.

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 15:51
CPC Classifications
C; C23; C23G; C23G5/00; C23G5/02; C23G5/04

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 149 words
A process for recovering solvent vapors in a vapor degreasing apparatus, according to the present invention, comprises the steps of: (a) subjecting vapors above a boiling solvent to a first heat exchanger cooling step at a temperature below the dew point of the solvent vapors but above 32° F. (0° C.); (b) subjecting vapors above the location of the first heat exchanger step to a second heat exchanger step at a temperature below 32° F. (0° C.); (c) subjecting vapors above the location of the second heat exchanger step to a third heat exchanger step at a temperature within about 5° C. of the temperature of the second heat exchanger step; and (d) isolating any recovered condensate produced from the third heat exchanger step such that it can be subjected to a drying step prior to being combined with condensate produced in the first and second heat exchanger steps.
Claim 2
Dependent Claim 149 words
A process for recovering solvent vapors in a vapor degreasing apparatus, according to the present invention, comprises the steps of: (a) subjecting vapors above a boiling solvent to a first heat exchanger cooling step at a temperature below the dew point of the solvent vapors but above 32° F. (0° C.); (b) subjecting vapors above the location of the first heat exchanger step to a second heat exchanger step at a temperature below 32° F. (0° C.); (c) subjecting vapors above the location of the second heat exchanger step to a third heat exchanger step at a temperature within about 5° C. of the temperature of the second heat exchanger step; and (d) isolating any recovered condensate produced from the third heat exchanger step such that it can be subjected to a drying step prior to being combined with condensate produced in the first and second heat exchanger steps.
Claim 3
Dependent Claim 39 words
A process for recovering solvent vapor according to claim 1 wherein the location where said subjecting vapors to a second heat exchanger occurs partially overlaps with the location where said subjecting vapors to a first heat exchanger step occurs.
Claim 4
Dependent Claim 31 words
A process for recovering solvent vapor according to claim 1 or 2 wherein the depth of freeboard to width ratio of the vapor degreaser is from about 1.0 to about 2.3.
Claim 5
Dependent Claim 36 words
A process for recovering solvent vapor according to claim 3 wherein subjecting vapors to a third heat exchanger step occurs from about 1.0 to about 12 inches below the top lip of the vapor degreasing apparatus.
Claim 6
Dependent Claim 138 words
A process for reducing emissions from vapor degreasing and defluxing equipment comprising the steps of: (a) subjecting vapors above a boiling solvent to a first heat exchanger cooling step at a temperature below the dew point of the solvent vapors but above 0° C.; (b) subjecting vapors above the location of the first heat exchanger cooling step to a second heat exchanger cooling step at a temperature less than the first cooling step, wherein the location of said subjecting to a second heat exchanger cooling step partially overlaps with the location of said subjecting vapors to a first heat exchanger cooling step; and (c) subjecting vapors above the location of the second heat exchanger cooling step to a third heat exchanger cooling step, wherein the third heat exchanger cooling step reduces the water vapor concentration entering the equipment.
Claim 7
Dependent Claim 138 words
A process for reducing emissions from vapor degreasing and defluxing equipment comprising the steps of: (a) subjecting vapors above a boiling solvent to a first heat exchanger cooling step at a temperature below the dew point of the solvent vapors but above 0° C.; (b) subjecting vapors above the location of the first heat exchanger cooling step to a second heat exchanger cooling step at a temperature less than the first cooling step, wherein the location of said subjecting to a second heat exchanger cooling step partially overlaps with the location of said subjecting vapors to a first heat exchanger cooling step; and (c) subjecting vapors above the location of the second heat exchanger cooling step to a third heat exchanger cooling step, wherein the third heat exchanger cooling step reduces the water vapor concentration entering the equipment.
Claim 8
Dependent Claim 136 words
A process for controlling the rate of vapor diffusion through the freeboard zone of vapor degreasing and defluxing equipment comprising the steps of: (a) subjecting the vapors above a boiling solvent to a lower primary heat exchanger which is operated at a temperature above 0° C.; (b) subjecting vapors above the location of the primary heat exchanger to an intermediate heat exchanger which is operated at a temperature below 0° C., and (c) subjecting vapors above the location of the intermediate heat exchanger to a third heat exchanger which is operated at a temperature within about 5° C. of the temperature of the intermediate heat exchanger, and located adjacent to the top of the freeboard zone thereby reducing the vapor concentration gradient of the vapor and controlling the rate of vapor diffusion through the freeboard zone.
Claim 9
Dependent Claim 136 words
A process for controlling the rate of vapor diffusion through the freeboard zone of vapor degreasing and defluxing equipment comprising the steps of: (a) subjecting the vapors above a boiling solvent to a lower primary heat exchanger which is operated at a temperature above 0° C.; (b) subjecting vapors above the location of the primary heat exchanger to an intermediate heat exchanger which is operated at a temperature below 0° C., and (c) subjecting vapors above the location of the intermediate heat exchanger to a third heat exchanger which is operated at a temperature within about 5° C. of the temperature of the intermediate heat exchanger, and located adjacent to the top of the freeboard zone thereby reducing the vapor concentration gradient of the vapor and controlling the rate of vapor diffusion through the freeboard zone.
Claim 10
Dependent Claim 25 words
The process according to claim 1, 5 or 6 wherein said vapor comprises a member selected from the group consisting of CFC-11, HCFC-141b, and HCFC-123.
Claim 11
Dependent Claim 12 words
The process according to claim 7 wherein said vapor further comprises methanol.
Claim 12
Dependent Claim 20 words
The process according to claim 5 or 6 further comprising forming a condensate of said vapor and drying the condensate.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1995-09-01 1996-03-02 1996-09-01 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1999-09-01 2000-03-02 2000-09-01 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2003-09-01 2004-03-02 2004-09-01 $7700.00 Window Closed / Lapsed

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