US4082567A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for thermally killing roots in sewer lines
Assignee: Standard Oil Co
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Filing: 1976-07-26
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Granted: 1978-04-04
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Expires: 1996-07-26
Abstract
Abstract A heated fluid is used as a thermal herbicide for scalding and killing roots growing within sewer lines. The process includes the steps of heating a fluid, isolating a length of a sewer line, and then filling the isolated length of sewer line with the heated fluid for a lethal period of time required for the heated fluid to act as a thermal herbicide for killing the roots within the length of sewer line. When treating an adjacent length of the sewer line, the preheated fluid is removed from the preceeding section, reheated, and then inserted into the adjacent isolated length of the sewer line.
Inventors
- 👤 James T. Conklin
- 👤 Daniel R. Daley
- 👤 Raymond K. Geyer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 20:49
CPC Classifications
A; A01; A01M; A01M21/00; A01M21/04; B; B08; B08B; B08B9/00; B08B9/02; B08B9/027; E; E03; E03F; E03F9/00
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
107 words
A method for using a liquid to kill roots and other living matter in a sewer line, said method comprising the steps of: a. heating the liquid external to said sewer line; b. isolating a length of the sewer line from adjacent lengths of sewer line; c. filling said isolated length of sewer line with said heated liquid at a temperature sufficient to transfer a temperature of at least about 140° F. to all of the natural enzymes of said roots for a lethal period of time, thereby allowing said heated liquid to act as a thermal herbicide for killing the roots and other living matter therein.
Claim 2
Independent Claim
107 words
A method for using a liquid to kill roots and other living matter in a sewer line, said method comprising the steps of: a. heating the liquid external to said sewer line; b. isolating a length of the sewer line from adjacent lengths of sewer line; c. filling said isolated length of sewer line with said heated liquid at a temperature sufficient to transfer a temperature of at least about 140° F. to all of the natural enzymes of said roots for a lethal period of time, thereby allowing said heated liquid to act as a thermal herbicide for killing the roots and other living matter therein.
Claim 3
Dependent Claim
29 words
The method as described in claim 1 further comprising the steps of: d. removing said heated liquid from said isolated length of sewer line; and e. reheating said liquid.
Claim 4
Dependent Claim
62 words
The method as described in claim 2 further comprising the steps of: f. isolating one of said adjacent lengths of sewer line; and g. filling said isolated adjacent length of sewer line with said reheated liquid for a lethal period of time, thereby allowing said reheated liquid to act as a thermal herbicide for killing the roots and other living matter therein.
Claim 5
Independent Claim
13 words
The method as described in clai 3 wherein the liquid is primarily water.
Claim 6
Independent Claim
13 words
The method as described in clai 3 wherein the liquid is primarily water.
Claim 7
Dependent Claim
39 words
The method as described in claim 1 wherein said filling step further comprises the step of: soaking the roots within said isolated length of sewer line for a period of from 15 minutes to 60 minutes with said liquid.
Claim 8
Dependent Claim
40 words
The method as described in claim 3, further comprising the steps of: releasing from said isolated adjacent length of sewer line a portion of said liquid therein; and refilling said isolated adjacent length of sewer line with said reheated liquid.
Claim 9
Dependent Claim
34 words
The method as described in claim 2 wherein steps (a) and (e) for heating and reheating the liquid comprise the steps of: superheating another fluid; and injecting said superheated another fluid into the liquid.
Claim 10
Dependent Claim
28 words
The method as described in claim 7 wherein steps (a) and (e) further comprise the step of heating the liquid to a temperature of at least 180° F.
Claim 11
Dependent Claim
31 words
The method as described in claim 8 wherein said isolating step comprises the step of temporarily inserting an expandable plug at each end of said isolated adjacent length of sewer line.
Claim 12
Dependent Claim
20 words
The method as described in claim 9 wherein said isolated length of sewer line includes at least one manhole entrance.
Claim 13
Dependent Claim
27 words
The method as described in claim 1 wherein the liquid is generally non-toxic at ambient temperatures to the roots and other living matter in the sewer line.
Claim 14
Independent Claim
162 words
A method for using a non-toxic liquid to kill roots and other living matter in a sewer line which liquid is substantially non-toxic at ambient temperatures to the roots and other living matter in the sewer line, said process comprising the steps of: a. heating the liquid; b. isolating a first length of the sewer line from other adjacent lengths thereof; c. filling said isolated first length of sewer line with said heated liquid for a lethal period of time required for said heated liquid to act as a thermal herbicide for killing the roots and other living matter therein; d. removing said heated liquid from the sewer line; e. reheating the liquid; f. isolating an adjacent length of said sewer line; and g. filling said isolated adjacent length of sewer line with said reheated liquid for a lethal period of time required for said reheated liquid to act as a thermal herbicide for killing the roots and other living matter therein.
Claim 15
Independent Claim
162 words
A method for using a non-toxic liquid to kill roots and other living matter in a sewer line which liquid is substantially non-toxic at ambient temperatures to the roots and other living matter in the sewer line, said process comprising the steps of: a. heating the liquid; b. isolating a first length of the sewer line from other adjacent lengths thereof; c. filling said isolated first length of sewer line with said heated liquid for a lethal period of time required for said heated liquid to act as a thermal herbicide for killing the roots and other living matter therein; d. removing said heated liquid from the sewer line; e. reheating the liquid; f. isolating an adjacent length of said sewer line; and g. filling said isolated adjacent length of sewer line with said reheated liquid for a lethal period of time required for said reheated liquid to act as a thermal herbicide for killing the roots and other living matter therein.
Claim 16
Dependent Claim
53 words
The method as described in claim 12 wherein step (g) comprises the steps of: g1. filling said isolated adjacent length of sewer line with said reheated liquid; g2. soaking said isolated adjacent sewer line with said reheated liquid for said lethal time sufficient to thermally kill the roots and other living material therein.
Claim 17
Dependent Claim
32 words
The method as described in claim 13 wherein step (g) further comprises the step of: g3. maintaining the temperature of said reheated liquid above 140° F. for said lethal period of time.
Claim 18
Dependent Claim
31 words
The method as described in claim 14 wherein step (g1) further comprises the step of inducing additional hydrostatic pressure on said reheated liquid within said isolated adjacent length of sewer line.
Claim 19
Dependent Claim
32 words
The method as described in claim 14 wherein step (e) comprises the steps of: e1. superheating another fluid; and e2. injecting said superheated another fluid into the liquid for reheating the liquid.
Claim 20
Dependent Claim
21 words
The method as described in claim 16 wherein said liquid comprises sewage removed from a preceeding section of the sewer line.
Claim 21
Dependent Claim
27 words
The method as described in claim 17 wherein step (e) further comprises the step of: e3. reheating the liquid to a temperature of at least 180° F.
Claim 22
Dependent Claim
26 words
The method as described in claim 18 wherein said step (f) comprises the step of temporarily inserting expandable plugs into said adjacent length of sewer line.
Claim 23
Dependent Claim
26 words
The method as described in claim 12 further comprising the step of: h. repeating steps (d) through (g) for each subsequent length of said sewer line.
Claim 24
Dependent Claim
82 words
The method as described in claim 12 further comprising the steps of: i. removing root samples from said isolated adjacent length of sewer line after said lethal period of time; j. pulverizing the root samples; k. mixing a small amount of pyrocatechin with the pulverized root samples; l. filtering particulate matter from the mixture; and m. observe the color of the mixture after a 5 minute reaction period and if the color remains clear then proceed to repeat steps (d) through (h).
References Cited (Backward Citations)
US2251080A
Cited
US2976191A
Cited
US3171150A
Cited
US3600225A
Cited
US3535161A
Cited
US3741807A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-04-03 | 1981-10-03 | 1982-04-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-04-03 | 1985-10-03 | 1986-04-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-04-03 | 1989-10-03 | 1990-04-04 | $7700.00 | Window Closed / Lapsed |