Method and apparatus for treatment of contaminated soil

• US 20040123881A1
• Filed: 06/17/2002
• Published: 07/01/2004
• Est. Priority Date: 06/17/2002
• Status: Abandoned Application

• Current Assignee: Norman L. Desautels
• Original Assignee: Norman L. Desautels
• Inventors: Desautels, Norman L.
• Application Number:
  US10/172,022
• Publication Number:
  US 20040123881A1
• Time in Patent Office: Days
• US Class Current: 134/25.1
• CPC Class Codes: B09C 1/00 Reclamation of contaminated soil
• CPC Class Codes: B09C 1/02 Extraction using liquids, e.g. washing, leaching , flotation
• CPC Class Codes: B09C 1/08 chemically

Abstract

The apparatus of the invention comprises a plurality of vessels, each vessel having a soil intake opening, a soil discharge opening, and a soil motivator associated therewith. The apparatus also has a liquid delivery system configured to deliver a liquid into at least one of the vessels, and a drainage system configured to collect the liquid and the contaminants. The vessels are arranged in sequence so that soil discharged from the discharge opening of one vessel is directly deposited into the intake opening of the next vessel. The method of the invention comprises the steps of: introducing the contaminated soil into a first vessel; washing the soil with a first liquid cleaning agent; passing the soil through a plurality of vessels in sequence wherein said first liquid cleaning agent is removed by a second liquid cleaning agent and water; draining said second liquid cleaning agent and water from the soil; and, rinsing the soil with water.

Claims

1. An apparatus for treatment of soil that contains contaminants, the apparatus comprising:

a plurality of vessels, each of said vessels having a soil intake opening and a soil discharge opening;

a plurality of soil motivators, each of said motivators associated with one of said vessels, said motivators operable to move soil through the associated vessel from said intake opening to said discharge opening;

a liquid delivery system configured to deliver a liquid into at least one of said vessels; and

a drainage system configured to collect said liquid and said contaminants;

wherein said vessels are inclined so that the intake opening is at a lower level than the discharge opening, and said vessels are arranged in sequence so that soil discharged from the discharge opening of one of said vessels falls into the intake opening of the next said vessel.

2. The apparatus of claim 1 wherein each of said intake openings is near a first end of one of said vessels, and each of said discharge openings is near a second end of one of said vessels.

3. The apparatus of claim 2 wherein the vessels are inclined at angles in the range of 10 to 40 degrees, and the second end of one of said vessels is above the first end of the next said vessel.

4. The apparatus of claim 3 wherein the angles of the vessels is in the range of 25 to 30 degrees.

5. The apparatus of claim 3 wherein the soil motivators comprise rotatable shafts with a plurality of paddles attached thereto.

6. The apparatus of claim 5 wherein the paddles are symmetrically disposed around said rotatable shafts.

7. The apparatus of claim 5 wherein the paddles extend radially outward from the shafts in pairs.

8. The apparatus of claim 7 wherein adjacent pairs of paddles are perpendicular to each other.

9. The apparatus of claim 5 wherein the paddles are oriented so that when said shafts are rotated in a forward sense, said paddles move soil towards said discharge opening.

10. The apparatus of claim 8 wherein the paddles are oriented so that when said shafts are rotated in a forward sense, said paddles move soil towards said discharge opening.

11. The apparatus of claim 3 wherein the vessels comprise cylindrical drums.

12. The apparatus of claim 11 wherein the first end of at least one of the drums is closed and the second end of at least one of the drums is open.

13. The apparatus of claim 11 wherein the motivator in at least one of said drums comprises a screened cylinder attached to a rotatable shaft, said screened cylinder having a plurality of paddles therein.

14. The apparatus of claim 13 wherein the drainage system for said at least one of said drums comprises a plurality of slots on the underside of said at least one of said drums.

15. The apparatus of claim 11 wherein at least one of said cylindrical drums comprises a rearward portion and a forward portion, said forward portion having a diameter greater than a diameter of said rearward portion, and wherein said paddles in said forward portion have a screened cylinder attached to the outermost portions thereof.

16. The apparatus of claim 1 wherein the drainage system comprises at least one slot on an underside of at least one of said vessels.

17. The apparatus of claim 1 wherein the drainage system comprises a screened portion on an underside of at least one of said vessels.

18. The apparatus of claim 17 wherein the screened portion is adjacent to the discharge opening.

19. The apparatus of claim 18 wherein the screened portion has a mesh size in the range of 20 to 80 mesh.

20. The apparatus of claim 12 wherein the drainage system comprises a screened portion on an underside of at least one of said drums.

21. The apparatus of claim 20 wherein the screened portion is adjacent the second end.

22. The apparatus of claim 21 wherein the screened portion has a mesh size in the range of 20 to 80 mesh.

23. The apparatus of claim 21 wherein the drainage system further comprises at least one slot on at least one of the drums.

24. The apparatus of claim 23 wherein the slot is oriented generally horizontally along a side of said drum, said slot extending from said screened portion towards said first end.

25. The apparatus of claim 5 wherein said paddles have replaceable wear plates attached thereon.

26. The apparatus of claim 11, the apparatus further comprising a trailer having an intake conveyor and a discharge conveyor mounted thereon, wherein said drums are positioned on said trailer so that said intake conveyor deposits soil into a first of said drums, and soil exiting a last of said drums is deposited on said discharge conveyor.

27. The apparatus of claim 1 wherein the drainage system comprises a skimming system, the skimming system comprising a gutter and skimming plates, wherein said skimming plates are positioned in said gutter so that said liquid and said contaminants delivered to said gutter flows over said skimming plates, and soil mixed in with said liquid and said contaminants is caught by said skimming plates.

28. A vessel for treatment of soil that contains contaminants, the vessel comprising:

a cylindrical drum having a soil intake opening and a soil discharge opening;

a soil motivator operable to move soil through said vessel from said intake opening to said discharge opening; and

a liquid delivery system configured to deliver a liquid into said cylindrical drum;

wherein the vessel is inclined at an angle between 10 and 40 degrees so that the intake opening is at a lower level than the discharge opening.

29. The vessel of claim 28 further comprising a drainage system configured to collect said liquid and said contaminants.

30. The vessel of claim 28 wherein said soil motivator comprises a rotatable shaft with a plurality of paddles attached thereto.

31. The vessel of claim 30 wherein said cylindrical drum comprises a rearward portion and a forward portion, said forward portion having a diameter greater than a diameter of said rearward portion, and wherein said paddles in said forward portion have a screened cylinder attached to the outermost portions thereof.

32. The vessel of claim 31 wherein the drainage system comprises a plurality of generally circumferential slots in an underside of said forward portion.

33. An apparatus for treatment of soil that contains contaminants, the apparatus comprising:

at least four cylindrical drums, each of said drums having a soil intake opening and a soil discharge opening, said drums positioned at an incline so that the intake opening is at a lower level than the discharge opening, and said drums arranged in sequence so that soil discharged from the discharge opening of one of said drums falls into the intake opening of the next said drum, each of said drums other than a first of said drums having a liquid removal system in a forward portion thereof;

a soil motivator associated with each of said drums, said motivators operable to move soil through the associated drum from said intake opening to said discharge opening;

a liquid delivery system configured to deliver a first liquid cleaning agent into the first of said drums, a second liquid cleaning agent into another of said drums subsequent to said first drum, and water into the rest of said drums, and

a drainage system configured to collect liquids and said contaminants escaping from said liquid removal systems.

34. A method for treating soil that contains contaminants, the method comprising:

introducing the contaminated soil into a first vessel;

washing the soil with a first liquid cleaning agent;

passing the soil through a plurality of vessels in sequence wherein said first liquid cleaning agent is removed by a second liquid cleaning agent and water;

draining said second liquid cleaning agent and water from the soil; and

rinsing the soil with water.

35. A method of treating soil that contains contaminants, the method comprising:

introducing the contaminated soil and a first liquid chemical into a first vessel, said first vessel having an intake opening through which said soil is inserted, and a discharge opening;

agitating the soil and the first liquid chemical in said first vessel;

discharging the soil and a portion of the first liquid chemical from said discharge opening of said first vessel directly into an intake opening of a second vessel;

introducing water into said second vessel along with the soil and said portion of the first liquid chemical;

agitating the soil, said portion of the first liquid chemical and the water in said second vessel;

draining said portion of the first liquid chemical and the water from said second vessel;

discharging the soil from a discharge opening in said second vessel directly into an intake opening of a third vessel;

introducing a second liquid chemical and more water into said third vessel along with the soil;

agitating the soil, said second liquid chemical and water in said third vessel;

draining said second liquid chemical and water from said third vessel;

discharging the soil from a discharge opening in said third vessel directly into an intake opening of a rinsing vessel;

rinsing the soil in said rinsing vessel;

discharging the soil into a final vessel; and

separating water from the soil in said final vessel.