In situ method and apparatus for biodegradation of alkyl ethers and tertiary butyl alcohol
AssigneeShell Oil Company
InventorsJoseph Patrick Salanitro, Paul Carr Johnson, Stephen Merle Stearns, Paul Michael Maner, James Henry Miller, Gerard Eugene Spinnler
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Abstract
A method and apparatus for the in situ purification of aquifers contaminated with ethers and/or alcohols using a bacterial culture, a method of delivering the culture to the subsurface, and an oxygen delivery system.
Claims20
A method for in situ remediation of an aquifer having a treatment zone through which passes water contaminated with at least one chemical contaminant which method comprises:
- a) delivering to the treatment zone a microbial culture capable of degrading at least one chemical contaminant present in said aquifer;
- and
- b) injecting, by at least two conduits, an oxygen-containing gas at a pressure of at least 5 psig above the hydrostatic pressure at injection points with injection frequency and volume at each injection point having the relationship according to the following equation:
- e[(−V×F×N×H)/(W×B×Q)]>0.50
- Wherein:
- e=natural exponential
- V=volume of gas injected at each injection point (ft3)
- F=frequency of injections (number of injections per day)
- N=number of gas injection points
- W=width of the treatment zone perpendicular to groundwater flow path (ft)
- B=vertical thickness of treatment zone (ft)
- Q=specific discharge of treatment zone to the treatment zone (ft/day)
- H=Henry's Constant for contaminant of interest ((mg/L-water)/(mg/L-air))
A method for in situ remediation of an aquifer having a treatment zone through which passes water contaminated with at least one chemical contaminant which method comprises:
- a) injecting, by at least two conduits, an oxygen-containing gas at a pressure of at least 5 psig above the hydrostatic pressure at injection points;
- and
- b) delivering to the treatment zone a microbial culture capable of degrading at least one chemical contaminant;
- wherein, the loss of contaminant(s) from volatilization is less than 50% by weight.
A method for in situ remediation of an aquifer having a treatment zone through which passes water contaminated with at least one chemical contaminant which method comprises:
- a) injecting, by at least two conduits, an oxygen-containing gas at a pressure of at least 5 psig above the hydrostatic pressure at injection points at a frequency of from about once a week to about ten times a day;
- and
- b) delivering to the treatment zone a microbial culture capable of degrading at least one chemical contaminant.
A method for in situ remediation of oxygenate chemical(s) in an aquifer having a treatment zone through which passes water contaminated with oxygenate chemicals, which method comprises:
- a) delivering to the treatment zone a microbial culture capable of degrading at least one oxygenate chemical contaminant;
- and
- b) injecting, by at least two conduits, an oxygen-containing gas at a pressure of at least 5 psig above the hydrostatic pressure at injection points with injection frequency and volume at each injection point having the relationship according to the following equation:
- e[(−V×F×N×H)/(W×B×Q)]>0.90
- Wherein:
- e=natural exponential
- V=volume of gas injected at each injection point (ft3)
- F=frequency of injections (number of injections per day)
- N=number of gas injection points
- W=width of treatment zone perpendicular to groundwater flow path (ft)
- B=vertical thickness of treatment zone (ft)
- Q=specific discharge of groundwater to treatment zone (ft/day)
- H=Henry's Constant for contaminant of interest ((mg/L-water)/(mg/L-air))
- Wherein the loss of contaminant from volatilization and/or dispersion is less than 10% by weight;
- wherein the oxygen-containing gas is injected to the aquifer by at least two gas injectors having respective perforated sections located at least two different depths within the aquifer;
- wherein the oxygen-containing gas is injected to the aquifer by a plurality of gas injectors spaced less than 10 ft apart;
- wherein each injection of oxygen-containing gas at each injection point lasts from about 0.05 to about 4 minutes.
Dependencies are inferred from the claim text.