Patent US4005997A successfully refreshed from Google Patents.
US4005997A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gas dehydration with liquid desiccants and regeneration thereof
Assignee: Dow Chemical Co
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Filing: 1975-02-24
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Granted: 1977-02-01
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Expires: 1995-02-24
Abstract
Abstract Natural or industrial gas streams are dehydrated with liquid organic desiccants and the desiccants are treated in a thermal reconcentration zone to remove a major portion of the water contained therein followed by treatment in an isothermal azeotroping zone to remove substantially all the remaining water with low energy requirements.
Inventors
- 👤 Allan E. Fowler
- 👤 John E. Protz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 14:38
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/26; B01D53/263; B01D3/00; B01D3/34; B01D3/36; C; C10; C10G; C10G2300/00; C10G2300/10; C10G2300/1025
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
218 words
The method of increasing the dew point depression of a gas stream using low energy requirements which comprises a. contacting a moisture laden gas stream with a substantially completely dehydrated liquid organic desiccant in a contacting zone to generate a gas stream having an increased dew point depression and a water rich liquid organic desiccant, b. heating said water rich liquid organic desiccant from said contactor zone in a thermal reconcentration zone heated to a temperature varying between the boiling point of said water rich desiccant and the decomposition temperature of the pure desiccant whereby a major portion of the water is removed from said liquid desiccant, c. contacting said partially dried liquid desiccant with a hydrocarbon azeotroping agent which is substantially insoluble in said desiccant and which boils in the range from about 35° to about 235° C. or mixtures thereof, in an azeotroping zone uniformly heated to a temperature in the range from about 5° to about 40° C. below the decomposition temperature of the pure desiccant whereby substantially all the remaining water is removed from said liquid desiccant, d. recovering the water-hydrocarbon azeotrope, e. separating the hydrocarbon azeotrope from excess water, f. recycling said azeotrope to said azeotroping zone, g. recovering a dehydrated organic desiccant, and h. recycling said dehydrated desiccant to said contacting zone.
Claim 2
Independent Claim
218 words
The method of increasing the dew point depression of a gas stream using low energy requirements which comprises a. contacting a moisture laden gas stream with a substantially completely dehydrated liquid organic desiccant in a contacting zone to generate a gas stream having an increased dew point depression and a water rich liquid organic desiccant, b. heating said water rich liquid organic desiccant from said contactor zone in a thermal reconcentration zone heated to a temperature varying between the boiling point of said water rich desiccant and the decomposition temperature of the pure desiccant whereby a major portion of the water is removed from said liquid desiccant, c. contacting said partially dried liquid desiccant with a hydrocarbon azeotroping agent which is substantially insoluble in said desiccant and which boils in the range from about 35° to about 235° C. or mixtures thereof, in an azeotroping zone uniformly heated to a temperature in the range from about 5° to about 40° C. below the decomposition temperature of the pure desiccant whereby substantially all the remaining water is removed from said liquid desiccant, d. recovering the water-hydrocarbon azeotrope, e. separating the hydrocarbon azeotrope from excess water, f. recycling said azeotrope to said azeotroping zone, g. recovering a dehydrated organic desiccant, and h. recycling said dehydrated desiccant to said contacting zone.
Claim 3
Dependent Claim
18 words
The method as set forth in claim 1 wherein the gas stream treated is a natural gas stream.
Claim 4
Dependent Claim
19 words
The method as set forth in claim 1 wherein the organic desiccant is a glycol of 2-12 carbon atoms.
Claim 5
Dependent Claim
15 words
The method as set forth in claim 3 wherein the glycol used is triethylene glycol.
Claim 6
Dependent Claim
26 words
The method as set forth in claim 1 wherein the azeotroping agent is an alkane having a boiling range from about 35° to about 235° C.
Claim 7
Dependent Claim
14 words
The method as set forth in claim 5 wherein the azeotroping agent is isooctane.
Claim 8
Independent Claim
183 words
The method of dehydrating a liquid organic desiccant with a hydrocarbon azeotroping agent which desiccant is useful to dehydrate a gas stream in a liquid-gas contactor zone which comprises a. heating a water rich liquid organic desiccant from said contactor zone in a thermal reconcentration zone heated to a temperature varying between the boiling point of said water rich desiccant and the decomposition temperature of the pure desiccant whereby a major portion of the water is removed from said liquid desiccant, b. contacting said partially dried liquid desiccant with a hydrocarbon azeotroping agent which is substantially insoluble in said desiccant and which boils in the range from about 35° to about 235° C. or mixtures thereof in an azeotroping zone uniformly heated to a temperature in the range from about 5° to about 40° C. below the decomposition temperature of the pure desiccant whereby substantially all the remaining water is removed from said liquid desiccant, c. recovering a water-hydrocarbon azeotrope, d. separating the hydrocarbon azeotrope from excess water, e. recycling said azeotrope to said azeotroping zone, and f. recovering a dehydrated organic desiccant.
Claim 9
Independent Claim
183 words
The method of dehydrating a liquid organic desiccant with a hydrocarbon azeotroping agent which desiccant is useful to dehydrate a gas stream in a liquid-gas contactor zone which comprises a. heating a water rich liquid organic desiccant from said contactor zone in a thermal reconcentration zone heated to a temperature varying between the boiling point of said water rich desiccant and the decomposition temperature of the pure desiccant whereby a major portion of the water is removed from said liquid desiccant, b. contacting said partially dried liquid desiccant with a hydrocarbon azeotroping agent which is substantially insoluble in said desiccant and which boils in the range from about 35° to about 235° C. or mixtures thereof in an azeotroping zone uniformly heated to a temperature in the range from about 5° to about 40° C. below the decomposition temperature of the pure desiccant whereby substantially all the remaining water is removed from said liquid desiccant, c. recovering a water-hydrocarbon azeotrope, d. separating the hydrocarbon azeotrope from excess water, e. recycling said azeotrope to said azeotroping zone, and f. recovering a dehydrated organic desiccant.
Claim 10
Dependent Claim
19 words
The method as set forth in claim 7 wherein the organic desiccant is a glycol of 2-12 carbon atoms.
Claim 11
Dependent Claim
15 words
The method as set forth in claim 8 wherein the glycol used is triethylene glycol.
Claim 12
Dependent Claim
26 words
The method as set forth in claim 7 wherein the azeotroping agent is an alkane having a boiling range from about 35° to about 235° C.
Claim 13
Dependent Claim
14 words
The method as set forth in claim 10 wherein the azeotroping agent is isooctane.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-02-01 | 1980-08-02 | 1981-02-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-02-01 | 1984-08-02 | 1985-02-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-02-01 | 1988-08-02 | 1989-02-01 | $7700.00 | Window Closed / Lapsed |