Contaminant extractor and method

Abstract

An improved method and apparatus for removal of .Iadd.contaminants such as .Iaddend.petroleum hydrocarbons from contaminated soil. The apparatus of the invention includes a shallow container, preferably with vertical sides, which has in its bottom wall a multiplicity of elongated recessed chambers with an open mesh entry area at the upper side, and a gas discharge orifice at one end of each chamber. A rack containing burners is adapted for positioning over the material to be treated within the container. The invented method includes charging materials to be treated into a container, heating the material while creating a partial pressure within the chamber, establishing a vacuum to pull the gasses downwardly through the soil and atmospheric air downwardly with the gasses, then either collecting or discharging the removed gasses, after which the soil is removed from the treatment chamber.

What is claimed is: 
     
       1. . .A.!. .Iadd.The .Iaddend.method . .for removing hydrocarbons from soil, comprising placing the soil in an open container, heating the soil and the entrained hydrocarbons by directing heat against the soil; creating a sub-atmospheric pressure within the soil by establishing a vacuum beneath the soil;   vaporizing the hydrocarbons within the soil;   removing the vaporized hydrocarbons downardly from beneath the soil;   withdrawing the vaporized hydrocarbon from beneath the soil; and   discharging the vaporized hydrocarbons.!. .Iadd.of claim 22 wherein said organic contaminants are selected from the group consisting of hydrocarbons and their derivatives.Iaddend..   
     
     
       2. A method according to claim 1, further comprising collecting the . .discharged.!. .Iadd.withdrawn .Iaddend.vaporized hydrocarbons. 
     
     
       3. A method according to claim .Iadd.1 .Iaddend.wherein the heating is accomplished by radiant heating. 
     
     
       4. A method according to claim .Iadd.1 .Iaddend.wherein the heating is accomplished by infrared heating. 
     
     
       5. A method according to claim 1, wherein the soil is placed in the container in generally loose form. 
     
     
       6. A method according to claim 1, wherein the soil is placed in the container to a generally even depth. . .7. A method according to claim 1, further comprising collecting the discharged gasses..!.. .8. A method according to claim 1, further comprising heating ambient air above the soil, and drawing the heated ambient air downwardly with the vaporized 
     
     
        gasses..!.9. A method according to claim 1, wherein the vacuum created 
     
     
        beneath the soil is from 2 to 10 inches of mercury. 10. Apparatus for treating soil, comprising: a shallow container, having vertical sides and a bottom wall;   a multiplicity of recessed chambers beneath said bottom wall, and fixed thereto;   said bottom wall being provided with orifices for gas communication between said container and said chambers;   means communicating with said chambers for removing gases from said chambers and said container; and   
     
     
       means for heating the interior of said container. 11. Apparatus according 
     
     
        to claim 10, wherein said means for removing gases is a vacuum pump. 12. Apparatus according to claim 11, wherein said means for removing gases includes each vacuum chamber having a vacuum tube situated therein, 
     
     
        communicating with said vacuum pump. 13. Apparatus according to claim 12, 
     
     
        wherein each vacuum tube is surrounded by pea gravel. 14. Apparatus according to claim 10, wherein one of said vertical sides is hinged to 
     
     
        said bottom wall. 15. Apparatus according to claim 10, wherein said means for heating the interior of said container is a heater mounted above and spaced from the bottom wall of said container, and adapted to hear the 
     
     
        upper surface of material in said container generally evenly. 16. Apparatus according to claim 15, further comprising means for moving said heater from a stand-by position adjacent said container to an 
     
     
        operating position over said container. 17. Apparatus according to claim 15, comprising a rack having at least one heater mounted therein, track means associated with said containers and track engaging means associated 
     
     
        with said rack. 18. Apparatus according to claim 17, wherein said track 
     
     
        engaging means are wheels journalled on said rack. 19. Apparatus according 
     
     
        to claim 15, wherein said heater is a radiant heater. 20. Apparatus 
     
     
        according to claim 15, wherein said heater is an infrared heater. 21. Apparatus according to claim 10, further comprising means attached to one end of said container for lifting such end and substantially emptying said container. .Iadd.22. A method for removing organic contaminants from soil, comprising placing the soil in an open container, heating the soil and the entrained organic contaminants by directing heat against the soil; creating a sub-atmospheric pressure within the soil by establishing a vacuum beneath the soil;   vaporizing the contaminants within the soil;   removing the vaporized contaminants downwardly from the soil; and   withdrawing the vaporized contaminants from beneath the soil. .Iaddend..Iadd.23. A method according to claim 22, further comprising collecting the withdrawn vaporized contaminants. .Iaddend..Iadd.24. A method according to claim 22, wherein the heating is accomplished by radiant heating. .Iaddend..Iadd.25. A method according to claim 22, wherein the heating is accomplished by infrared heating. .Iaddend..Iadd.26. A method according to claim 22, wherein the soil is placed in the container in generally loose form. .Iaddend..Iadd.27. A method according to claim 22, wherein the soil is placed in the container to a generally even depth. .Iaddend..Iadd.28. A method according to claim 22, further comprising heating ambient air above the soil, and drawing the heated ambient air downwardly with the vaporized contaminants. .Iaddend..Iadd.29. A method according to claim 22, wherein the vacuum beneath the soil is from 2 to 10 inches of mercury.