US3925047A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Removal of moisture from a natural gas stream by contacting with a liquid desiccant-antifreeze agent and subsequently chilling
Assignee: Phillips Petroleum Co
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Filing: 1973-12-03
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Granted: 1975-12-09
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Expires: 1993-12-03
Abstract
Abstract A moisture-containing gas is contacted with a liquid desiccantantifreeze agent in such a manner as to remove at least a portion of the moisture in the gas and introduce a sufficient amount of said agent in vapor phase into said gas to prevent the formation of solids in subsequent processing steps.
Inventors
- 👤 Ernest A Harper
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 22:42
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/26; C; C07; C07C; C07C7/00; C07C7/11
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
225 words
A PROCESA FOR REDUCING THE MOISTURE CONTENT OF A MOISTURE-CONTAINING GAS STREAM WITHOUT SUBSTANTIAL MOISTURE REMOVAL PRIOR TO INJECTING AN ANTIFREEZE AGENT INTO SAID GAS STREAM SO AS TO PREVENT SOLIDS FORMATION IN SAID GAS STREAM IN A SUBSEQUENT LOW TEMPERATURE PROCESING STEP, WHICH PROCESS COMPRISES: CONTACTING SAID GAS STREAM WHICH IS AT AN ATMOSPHERIC TEMPERATURE IN THE RANGE 40:-125*F WITH AN AQUEOUS LIQUID SOLUTION CONTAINING 521 TO 90 WEIGHT PERCENT OF A LOW BOILING (HIGH VAPOR PRESSURE) DESICCANT-ANTIFREEZE AGENT AND 49 TO 10 WEIGHT PERCENT WATER IN AN AMOUNT AND AT A TEMPERATURE IN THE RANGE 40*-125*F AND PRESSURE CONDITIONS WHICH ARE SUFFICIENT TO (A) ABSORB A MAJOR AMOOUNT OF SAID MOISTURE FROM SAID GAS STREAM INTO SAID AGENT TO FORM A WATER-AGENT SOLUTION AND (B) SIMULTANEOUSLY VAPORIZE AN AMOUNT OF SAID AGENT INTO SAID GAS STREAM REMOVED FROM SAID CONTACTING SUFFICIENT OT PREVENT SAID SOLIDS FORMATION FROM RESIDUAL MOISTURE REMAINING IN SAID GAS STREAM IN A SUBSEQUENT LOW TEMPERATURE PROCESSING OPERATION, AND CHILLING SAID GAS STREAM TO A TEMPERATURE SUFFICIENT TO CONDENSE SUBSTANTIALLY ALL OF THE PROPANE ANDHEAVIER HYDROCARBONS THEREFROM AND FORM A CONDENSATE COMPRISING SAID CONDENSED PROPANE AND HEAVIER HYDROCARBONS, WATER, AND SAID AGENT, BUT AT A TEMPERATURE SUFFICIENTLY ABOVE THE EUTECTIC FREEZING POINT FOR THE WATER-AGENT SOLUTION TO PREVENT FREEZING OF THE WATER-AGENT SOLUTION AND FORMATION OF SOLIDS DURING SAID CHILLING.
Claim 2
Dependent Claim
225 words
A PROCESA FOR REDUCING THE MOISTURE CONTENT OF A MOISTURE-CONTAINING GAS STREAM WITHOUT SUBSTANTIAL MOISTURE REMOVAL PRIOR TO INJECTING AN ANTIFREEZE AGENT INTO SAID GAS STREAM SO AS TO PREVENT SOLIDS FORMATION IN SAID GAS STREAM IN A SUBSEQUENT LOW TEMPERATURE PROCESING STEP, WHICH PROCESS COMPRISES: CONTACTING SAID GAS STREAM WHICH IS AT AN ATMOSPHERIC TEMPERATURE IN THE RANGE 40:-125*F WITH AN AQUEOUS LIQUID SOLUTION CONTAINING 521 TO 90 WEIGHT PERCENT OF A LOW BOILING (HIGH VAPOR PRESSURE) DESICCANT-ANTIFREEZE AGENT AND 49 TO 10 WEIGHT PERCENT WATER IN AN AMOUNT AND AT A TEMPERATURE IN THE RANGE 40*-125*F AND PRESSURE CONDITIONS WHICH ARE SUFFICIENT TO (A) ABSORB A MAJOR AMOOUNT OF SAID MOISTURE FROM SAID GAS STREAM INTO SAID AGENT TO FORM A WATER-AGENT SOLUTION AND (B) SIMULTANEOUSLY VAPORIZE AN AMOUNT OF SAID AGENT INTO SAID GAS STREAM REMOVED FROM SAID CONTACTING SUFFICIENT OT PREVENT SAID SOLIDS FORMATION FROM RESIDUAL MOISTURE REMAINING IN SAID GAS STREAM IN A SUBSEQUENT LOW TEMPERATURE PROCESSING OPERATION, AND CHILLING SAID GAS STREAM TO A TEMPERATURE SUFFICIENT TO CONDENSE SUBSTANTIALLY ALL OF THE PROPANE ANDHEAVIER HYDROCARBONS THEREFROM AND FORM A CONDENSATE COMPRISING SAID CONDENSED PROPANE AND HEAVIER HYDROCARBONS, WATER, AND SAID AGENT, BUT AT A TEMPERATURE SUFFICIENTLY ABOVE THE EUTECTIC FREEZING POINT FOR THE WATER-AGENT SOLUTION TO PREVENT FREEZING OF THE WATER-AGENT SOLUTION AND FORMATION OF SOLIDS DURING SAID CHILLING.
Claim 3
Dependent Claim
31 words
A process according to claim 1 wherein said agent is selected from the group consisting of methyl alcohol, ethyl alcohol, propyl alcohol, isopropyl alcohol, acetone, methyl ethyl ketone, and mixtures thereof.
Claim 4
Dependent Claim
67 words
A process according to claIm 1 wherein said agent comprises methyl alcohol, said water-agent solution is separated from said contacting and regenerated to remove agent therefrom, which agent is recycled to said contacting, and said gas stream removed from said contacting is chilled and passed to a separation zone from which a water-agent layer is withdrawn and regenerated along with said water-agent solution separated from said contacting.
Claim 5
Dependent Claim
47 words
A process according to claim 1 wherein said gas stream comprises natural gas and said agent comprises methyl alcohol and the amount of methyl alcohol vaporized into said gas stream is from about 50 to 5,000 pounds of agent per million cubic feet of gas being treated.
Claim 6
Dependent Claim
57 words
A process according to claim 4 wherein said agent comprises an aqueous methyl alcohol solution containing 60 to 85 weight percent of methyl alcohol and 40 to 15 weight percent of water and said natural gas consists essentially of methane and contains relatively small amounts of ethane, propane, butanes, and heavier hydrocarbons and is saturated with water.
Claim 7
Dependent Claim
213 words
A PROCESS ACCORDING TO CLAIM 1 COMPRISING THE STEPS OF: A. CONTACTING A NATURAL GAS STREAM COUNTERCURRENTLY IN A CONTACTING ZONE WITH SAID AGENT; B. WITHDRAWING A MOISTURE-ENCRICHED STREAM OF SAID AGENT FROM THE LOWER PORTION OF SAID CONTACTING ZONE AND PASSING SAME TO AN AGENT RECOVERY ZONE; C. WITHDRAWING FROM THE UPPER PORTION OF SAID CONTACTING ZONE A MOISTURE-LEAN STREAM OF SAID GAS NOW CONTAINING A SMALL AMOUNT OF SAID AGENT AND PASSING SAME TO A CHILLER ZONE, SAID AMOUNT OF SAID AGENT BEING SUFFICIENT TO PREVENT SAID SOLIDS FORMATION IN SAID CHILLER ZONE; D. PASSING SAID GAS STREAM FRO STEP (C) TO A PHASE SEPARATION ZONE; E. WITHDRAWING A TREATED GAS STREAM FROM SAID SEPARATION ZONE OF STEP (D) AS A PRODUCT OF THE PROCESS; F. PASSING A LIQUID PHASE COMPRISING CONDENSED HYDROCARBON AND SAID AGENT FROM SAID SPEARATION ZONE OF STEP (D) TO SAID AGENT RECOVERY ZONE; G. WITHDRAWING A STREAM OF CONDENSED HYDROCARBON FROM SAID AGENT RECOVERY ZONE AS ANOTHER PRODUCT OF THE PROCESS; H. WITHDRAWING A STREAM OF WATER FROM SAID AGENT RECOVERY ZONE; I. WITHDRAWING A STREAM COMPRISING REOCVERED LIQUID DESICCANT-ANTIFREEZE AGENT FROM SAID RECOVERY ZONE; AND J. RETURNING SAND RECOVERED AGENT OF STEP (I) TO SAID CONTACTING ZONE IN STEP (A) AS THE AGENT USED THEREIN.
Claim 8
Dependent Claim
12 words
A process according to claim 6 wherein said agent comprises methyl alcohol.
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) | 1978-12-08 | 1979-06-09 | 1979-12-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-08 | 1983-06-09 | 1983-12-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-08 | 1987-06-09 | 1987-12-09 | $7700.00 | Window Closed / Lapsed |