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.
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.