US4579596A
Expired / Lapsed
US
⏱️ 0.0 years remaining
In-situ removal of oily deposits from the interior surfaces of conduits
Assignee: Praxair Technology Inc
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Filing: 1984-11-01
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Granted: 1986-04-01
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Expires: 2004-11-01
Abstract
Abstract The in-situ cleaning of conduits containing oily deposits is facilitated by the concurrent passage of cleaning particles and a non-agglomerating drying agent therethrough in a propelling gas stream. In cycling cleaning operations, the preliminary injection of drying agent into the conduit prior to said concurrent use of cleaning particles and drying agent further enhances the overall in-situ cleaning operation.
Inventors
- 👤 Patrick J. Murzyn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 11:20
CPC Classifications
B; B08; B08B; B08B9/00; B08B9/02; B08B9/027; B08B9/04; B08B9/053; B08B9/057; B08B5/00; B08B9/032; B08B9/0321; B08B9/0328; B24; B24C; B24C3/00; B24C3/32; B24C3/325; B24C3/327; C; C10; C10G; C10G9/00; C10G9/14; C10G9/16; F; F28; F28G; F28G1/00; F28G1/12; B08B2230/00; B08B2230/01
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
231 words
In the in-situ process for cleaning the interior surfaces of conduits for the transport and/or processing of fluids, solids or mixtures thereof in which cleaning particles entrained in a propelling gas stream are passed through the conduit to be cleaned at an outlet gas velocity of from about 5,000 feet per minute up to the sonic velocity of the propelling gas, the improvement in the removal of an oily deposit comprising passing a drying agent through the conduit to be cleaned concurrently with the passage of said cleaning particles therethrough, said drying agent being (a) highly adsorptive or absorptive with respect to said oily deposit, (b) non-agglomerating so that, upon the adsorption and/or absorption of substantial amounts of the oily deposit during passage of said drying agent through the conduit to be cleaned, redeposition of said deposit at bends or other flow obstruction sites within the conduit downstream of the point of initial adsorption and/or absorption is effectively precluded, and (c) non-abrasive or non-erosive with respect to the surface of the conduit being cleaned, said drying agent being employed in an amount sufficient to effectively preclude the substantial embedding of said cleaning particles in or on the oil deposit being removed, whereby the effective in-situ cleaning action of the cleaning particles is enhanced, facilitating the application of said in-situ cleaning process to the treatment of conduits containing such oil deposits therein.
Claim 2
Dependent Claim
231 words
In the in-situ process for cleaning the interior surfaces of conduits for the transport and/or processing of fluids, solids or mixtures thereof in which cleaning particles entrained in a propelling gas stream are passed through the conduit to be cleaned at an outlet gas velocity of from about 5,000 feet per minute up to the sonic velocity of the propelling gas, the improvement in the removal of an oily deposit comprising passing a drying agent through the conduit to be cleaned concurrently with the passage of said cleaning particles therethrough, said drying agent being (a) highly adsorptive or absorptive with respect to said oily deposit, (b) non-agglomerating so that, upon the adsorption and/or absorption of substantial amounts of the oily deposit during passage of said drying agent through the conduit to be cleaned, redeposition of said deposit at bends or other flow obstruction sites within the conduit downstream of the point of initial adsorption and/or absorption is effectively precluded, and (c) non-abrasive or non-erosive with respect to the surface of the conduit being cleaned, said drying agent being employed in an amount sufficient to effectively preclude the substantial embedding of said cleaning particles in or on the oil deposit being removed, whereby the effective in-situ cleaning action of the cleaning particles is enhanced, facilitating the application of said in-situ cleaning process to the treatment of conduits containing such oil deposits therein.
Claim 3
Dependent Claim
20 words
The process of claim 1 in which said conduit comprises fired heater tubes to be decoked in the cleaning process.
Claim 4
Dependent Claim
15 words
The process of claim 1 in which said conduit to be cleaned comprises a pipeline.
Claim 5
Dependent Claim
15 words
The process of claim 1 in which said non-agglomerating drying agent comprises calcined diatomaceous earth.
Claim 6
Dependent Claim
13 words
The process of claim 4 in which said cleaning particles comprise steel shot.
Claim 7
Dependent Claim
20 words
The process of claim 4 in which said cleaning particles have a regular, non-random configuration with less than spherical symmetry.
Claim 8
Dependent Claim
14 words
The process of claim 4 in which said cleaning particles comprise flint or grit.
Claim 9
Dependent Claim
21 words
The process of claim 4 in which said outlet gas velocity is from about 7,000 to about 40,000 feet per minute.
Claim 10
Dependent Claim
39 words
The process of claim 1 in which said non-agglomerating drying agent is employed in an amount within the range of from about 5% to about 50% by weight based on the amount of cleaning particles passed through said conduit.
Claim 11
Dependent Claim
15 words
The process of claim 9 in which said non-agglomerating drying agent comprises calcined diatomaceous earth.
Claim 12
Dependent Claim
32 words
The process of claim 10 in which from about 10% to about 35% by weight of said drying agent is employed based on the amount of cleaning particles passed through said conduit.
Claim 13
Dependent Claim
20 words
The process of claim 10 in which said conduit comprises fired heater tubes to be decoked in the cleaning process.
Claim 14
Dependent Claim
15 words
The process of claim 10 in which said conduit to be cleaned comprises a pipeline.
Claim 15
Dependent Claim
66 words
The process of claim 1 and including injecting non-agglomerating drying agent into said conduit containing the oily deposit to be removed prior to said concurrent passage of said drying agent and said cleaning particles through said conduit in a cleaning run, the initial injection of said drying agent serving to coat the oily surface of the deposit to be removed and to facilitate the drying thereof.
Claim 16
Dependent Claim
66 words
The process of claim 14 in which, in each cleaning run, the flow of the cleaning particle-entrained gas stream is continued until the quantity of cleaning particles in a particle supply pot is exhausted, the preliminary injection of non-agglomerating drying agent into the conduit serving also to remove any cleaning particles that may have become embedded in or on the oily deposit during preceding cleaning runs.
Claim 17
Dependent Claim
15 words
The process of claim 15 in which said non-agglomerating drying agent comprises calcined diatomaceous earth.
Claim 18
Dependent Claim
20 words
The process of claim 16 in which said conduit comprises fired heater tubes to be decoked in the cleaning process.
Claim 19
Dependent Claim
15 words
The process of claim 16 in which said conduit to be cleaned comprises a pipeline.
Claim 20
Dependent Claim
13 words
The process of claim 17 in which said cleaning particles comprise steel shot.
Claim 21
Dependent Claim
21 words
The process of claim 19 in which said outlet gas velocity is from about 7,000 to about 40,000 feet per minute.
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) | 1989-03-31 | 1989-09-30 | 1990-04-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-03-31 | 1993-09-30 | 1994-04-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-03-31 | 1997-09-30 | 1998-04-01 | $7700.00 | Window Closed / Lapsed |