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US3880176A Expired / Lapsed US ⏱️ 0.0 years remaining

Apparatus for sewer treatment to kill tree roots and other organic growth therewithin

Assignee: Airrigation Engineering Co Inc
•
Filing: 1973-04-30
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Granted: 1975-04-29
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Expires: 1993-04-30
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Abstract

Abstract A composition for killing plant roots inside sewers, comprises an alkali metal alkyl dithiocarbamate in an amount of about 30%, a biodegradable liquid nonionic surfactant in an amount of about 12%, and water making up the remainder. One method for treating the sewer pipes comprises coating the inside wall of the pipe and any roots or other growth inside the pipe with the composition in the form of a foamy film by spraying it thereon or on the upper portion thereof, as from a continuously moving device. Preferred apparatus for so treating the sewer pipes comprises a sled having bottom skid means, a low center of gravity and a spray system mounted on said sled having generally upwardly directed nozzles, and means for pulling the sled through a pipe while supplying it with the composition under pressure. Another method comprises soaking with the solution diluted to about 2% of the methyldithiocarbamate, this being done by plugging the pipe and filling the pipe above the plug with the diluted solution. Special plugging apparatus is described.

Inventors

  • 👤 Frederick F Horne

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 16:36
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/50; E; E03; E03F; E03F9/00

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 109 words
Apparatus for treating root-infested sewer pipes including in combination a sled having a bottom skid for engaging the lower portion only of a pipe and a low center of gravity and open at its upper end, means for pulling said sled through a pipe, upwardly facing spray means for producing a diffuse, foaminducing spray, mounted on said sled and having upwardly directed nozzles for directing spray against the upper walls only of said pipe, and means for supplying a liquid aqueous mixture of phytocidal fumigant and surfactant under pressure to said spray means so that a phytocidal foam can be applied to the upper portions especially of said pipe.
Claim 2
Dependent Claim 109 words
Apparatus for treating root-infested sewer pipes including in combination a sled having a bottom skid for engaging the lower portion only of a pipe and a low center of gravity and open at its upper end, means for pulling said sled through a pipe, upwardly facing spray means for producing a diffuse, foaminducing spray, mounted on said sled and having upwardly directed nozzles for directing spray against the upper walls only of said pipe, and means for supplying a liquid aqueous mixture of phytocidal fumigant and surfactant under pressure to said spray means so that a phytocidal foam can be applied to the upper portions especially of said pipe.
Claim 3
Dependent Claim 26 words
The apparatus of claim 1, wherein said nozzles are two in number, each directing upwardly at 45* from vertical on opposite sides of the vertical axis.
Claim 4
Dependent Claim 29 words
The apparatus of claim 1 wherein said sled supports valve means for turning on and turning off the flow of said spray means to said means for supplying liquid.
Claim 5
Dependent Claim 16 words
The apparatus of claim 3 having elongated means connected to said valve for remote operation thereof.
Claim 6
Dependent Claim 16 words
The apparatus of claim 1 having means spraying under pressure at about 100 to 125 psi.
Claim 7
Dependent Claim 15 words
The apparatus of claim 1 wherein the means for supplying includes a reel of hose.
Claim 8
Dependent Claim 26 words
The apparatus of claim 1 wherein the means for pulling includes a coil spring cable and the means for supplying includes a conduit inside said cable.
Claim 9
Dependent Claim 26 words
The apparatus of claim 1 wherein the means for supplying includes a hose and the means for pulling includes a coil spring cable inside said hose.
Claim 10
Dependent Claim 24 words
The apparatus of claim 8 wherein said coil spring cable is close wound and the hose is elastomer filling the space outside the coil.

References Cited (Backward Citations)

US805534A Cited
US1274931A Cited
US1994616A Cited
US2501779A Cited
US2763288A Cited
US3370599A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1978-04-28 1978-10-28 1979-04-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1982-04-28 1982-10-28 1983-04-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1986-04-28 1986-10-28 1987-04-29 $7700.00 Window Closed / Lapsed

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