In-situ thermochemical solidification of dense non-aqueous phase liquids

• US 6,945,734 B1
• Filed: 03/16/2004
• Issued: 09/20/2005
• Est. Priority Date: 03/16/2004
• Status: Expired due to Fees

• Current Assignee: Gas Technology Institute (GTI Energy)
• Original Assignee: Gas Technology Institute (GTI Energy)
• Inventors: Hayes, Thomas D., Srivastava, Vipul J.
• Primary Examiner(s): KRECK, JOHN J
• Application Number:
  US10/801,185
• Publication Number:
  US 20050207847A1
• Time in Patent Office: 553 Days
• Field of Search: 405/128.1, 405/128.15, 405/128.2, 405/128.4, 405/128.6, 405/128.65, 405/128.9, 588/253
• US Class Current: 405/128.65
• CPC Class Codes: B09C 1/005 Extraction of vapours or gases using vacuum or venting
• CPC Class Codes: B09C 1/06 thermally
• CPC Class Codes: B09C 1/08 chemically

Abstract

A method for in-situ dense non-aqueous phase liquids treatment in which a subsurface source area comprising at least one rapid release contaminant is located and free water removed therefrom. The subsurface source area is then heated to a temperature suitable for extracting the at least one rapid release contaminant from the subsurface source area. The at least one rapid release contaminant is extracted from the subsurface source area, resulting in solidification of the dense non-aqueous phase liquids remaining in the subsurface source area.

Claims

1. A method for in-situ dense non-aqueous phase liquids treatment comprising the steps of:

locating a subsurface source area comprising at least one rapid release contaminant;

removing free water from said subsurface source area;

heating said subsurface source area to a temperature suitable for extracting said at least one rapid release contaminant from said subsurface source area; and

extracting said at least one rapid release contaminant from said subsurface source area, resulting in solidification of said dense non-aqueous phase liquids remaining in said subsurface source area.

2. A method in accordance with claim 1, wherein said at least one rapid release contaminant is extracted using vacuum extraction.

3. A method in accordance with claim 1, wherein a sweep gas is passed through said subsurface source area.

4. A method in accordance with claim 1, wherein said subsurface source area is heated to a temperature in a range of about 80°

C. to about 200°

C.

5. A method in accordance with claim 1, wherein said subsurface source area is heated by a dry heat source.

6. A method in accordance with claim 3, wherein said sweep gas is an inert gas.

7. A method in accordance with claim 6, wherein said inert gas is selected from the group consisting of air, nitrogen, helium and mixtures thereof.

8. A method in accordance with claim 3, wherein said sweep gas comprises at least one gaseous oxidant.

9. A method in accordance with claim 1, wherein said subsurface source area is identified by three dimensional mapping of PID/FID measurements.

10. A method in accordance with claim 2, wherein said vacuum extraction is carried out at a vacuum up to about 30 inches of mercury.

11. A method in accordance with claim 10, wherein said vacuum extraction is carried out at a vacuum in a range of about 5 to about 15 inches of mercury.

12. A method in accordance with claim 8, wherein said gaseous oxidant is ozone.