In-situ surfactant and chemical oxidant flushing for complete remediation of contaminants and methods of using same

• US 20080253840A1
• Filed: 10/31/2007
• Published: 10/16/2008
• Est. Priority Date: 11/06/2001
• Status: Active Grant

• Current Assignee: Tersus Environmental, Inc.
• Original Assignee: Surbec-art Environmental, LLC
• Inventors: Shiau, Bor-Jier
• Granted Patent: US 7,708,496 B2
• Time in Patent Office: Days
• US Class Current: 405/128.75
• CPC Class Codes: B09C 1/002 involving in-situ ground water treatment
• CPC Class Codes: B09C 1/02 Extraction using liquids, e.g. washing, leaching , flotation
• CPC Class Codes: B09C 1/08 chemically
• CPC Class Codes: B09C 2101/00 In situ
• CPC Class Codes: C09K 8/524 organic depositions, e.g. paraffins or asphaltenes
• CPC Class Codes: C09K 8/584 characterised by the use of specific surfactants

Abstract

The present invention relates to the removal of subsurface contaminants and methods of using same. In more particular, but not by way of limitation, the present invention relates to an integrated method for remediating subsurface contaminants through the use of a low concentration surfactant solution (and methods of making and using novel surfactant solutions) followed by an abiotic polishing process to thereafter achieve a substantially reduced subsurface contaminant concentration that surfactant flushing alone cannot achieve. The present invention is focused on remediation of high viscosity hydrocarbons, such as heating oils or coal tars, with a combination of pre-injection of bio-co-solvent and surfactant (and polymer) flush approach.

Claims

1. An abiotic process for polishing at least one surfactant remediated subsurface contaminant in order to further remediate at least one subsurface contaminant to substantially undetectable levels, comprising the step of:

introducing an effective amount of at least one pre-selected chemical oxidant capable of degrading the remaining at least one of subsurface contaminant to substantially undetectable levels.

2. The process of claim 1, wherein the effective amount of at least one pre-selected chemical oxidant is introduced by injection.

3. The process of claim 1, wherein at least one subsurface contaminant is a dense non-aqueous phase liquid.

4. The process of claim 1, wherein at least one subsurface contaminant is a light non-aqueous phase liquid.

5. The process of claim 1, wherein the effective amount of at least one pre-selected chemical oxidant is a free radical.

6. The process of claim 1, wherein the effective amount of at least one pre-selected chemical oxidant is selected from the group consisting of hydrogen peroxide, potassium permanganate, and combinations thereof.

7. A method for substantially removing subsurface contaminants, comprising the steps of:

introducing an effective amount of at least one pre-selected surfactant solution, comprising the steps of;

determining a contaminant solubilization of a surfactant system;

determining a surfactant sorption and precipitation of the surfactant system;

determining a surfactant non-aqueous phase liquid behavior properties of the surfactant system to assess a potential for surfactant losses under subsurface conditions; and

performing contaminant extraction-column studies to simulate flow through conditions in the aquifer;

introducing an effective amount of at least one pre-selected chemical oxidant, comprising the steps of;

determining relative reaction rates of the reactant;

determining the life span of the reactant;

evaluating the chemical demand associated with pH adjustment; and

identifying geochemical characteristics of the site;

wherein the effective amount of at least one pre-selected surfactant in combination with the effective amount of at least one pre-selected chemical oxidant is capable of substantially removing subsurface contaminants.

8. The method of claim 7, wherein the effective amount of a pre-selected biodegradable co-solvent is introduced first and the effective amount of at least one pre-selected surfactant solution is introduced second, the pre-selected chemical oxidant is then introduced to polish the final residual contaminant.

9. A method for determining chemical addition ratios and reaction times for a chemical oxidation system, comprising the steps of:

determining reaction kinetics;

determining pH conditions;

determining naturally occurring interference within the subsurface of the specific site; and

determining mobility control of the injected oxidant to the targeted area.

10. A subsurface contaminant site substantially remediated by the process comprising the steps of:

introducing an effective amount of at least one pre-selected surfactant solution; and

introducing an effective amount of at least one pre-selected chemical oxidant, wherein the effective amount of at least one pre-selected surfactant in combination with the effective amount of at least one pre-selected chemical oxidant is capable of substantially removing subsurface contaminants.

11. The substantially remediated site of claim 10, wherein the effective amount of the pre-selected subsurface contaminant is introduced first and the effective amount of at least one pre-selected chemical oxidant is introduced second.

12. The substantially remediated site of claim 10, wherein the pre-selected surfactant solution is selected from the group consisting of an anionic surfactant, a cationic surfactant, a nonionic surfactant or any combinations thereof and one or more combinations thereof.

13. The substantially remediated site of claim 10, wherein the pre-selected surfactant solution is a mixture of sodium dioctylsulfosuccinate and sodium dihexylsulfosuccinate.

14. The substantially remediated site of claim 10, wherein the pre-selected surfactant solution is a mixture of sodium dioctylsulfosuccinate and polyoxyethylene sorbitan monooleate.

15. The substantially remediated site of claim 10, wherein the pre-selected surfactant solution is a mixture of sodium dioctylsulfosuccinate and linear alkyl diphenyloxide disulfonate.

16. The substantially remediated site of claim 10, wherein the pre-selected surfactant solution is a mixture of alkylamine sodium sulfonate and sodium dihexylsulfosuccinate.

17. The substantially remediated site of claim 10, wherein at least one pre-selected chemical oxidant is a free radical.

18. The substantially remediated site of claim 10, wherein at least one pre-selected chemical oxidant is selected from the group consisting of hydrogen peroxide, potassium permanganate, and combinations thereof.

19. The substantially remediated site of claim 10, wherein the effective amount of at least one pre-selected surfactant solution is from about 0.05 weight % to about 15 weight %.

20. The substantially remediated site of claim 10, wherein the effective amount of at least one pre-selected surfactant solution is from about 3 weight % to about 8 weight %.

21. The substantially remediated site of claim 10, wherein the effective amount of at least one pre-selected surfactant solution is from about 1 weight % to about 3 weight %.

22. The substantially remediated site of claim 10, wherein the effective amount of at least one pre-selected surfactant solution is from about 0.05 weight % to about 1 weight %.

23. The substantially remediated site of claim 10, wherein at least one pre-selected surfactant solution is anionic.

24. The substantially remediated site of claim 10, wherein at least one pre-selected surfactant solution is nonionic.

25. A subsurface contaminant site substantially remediated by the process comprising the steps of:

introducing at least one surfactant solution capable of remediating at least one subsurface contaminant; and

sequentially introducing at least one pre-selected chemical oxidant.

26. The substantially remediated site of claim 25, wherein the pre-selected chemical oxidant is introduced by the method of injection.

27. The substantially remediated site of claim 25, wherein at least one subsurface contaminant is a dense non-aqueous phase liquid.

28. The substantially remediated site of claim 25, wherein at least one subsurface contaminant is a light non-aqueous phase liquid.