Prevention and remediation of petroleum reservoir souring and corrosion by treatment with virulent bacteriophage
There is provided a safe, natural, environmentally sound means of controlling bacterial contamination, corrosion, and souring of oil and gas wells and reservoirs that result from bacteria-contaminated water in a well. In one aspect it is a process for remediation of souring of petroleum reservoirs and coalbeds by adding to the water used in flooding and “fracing” operations an effective amount of virulent (non-lysogenic) bacteriophages (phages) specific for problematic target bacteria. The invention also provides a means for combating loss of effectiveness of bacterial control by staging bacteriophage production and application to control dominant and sub-dominant target bacteria in a community of target bacteria.
1. A process for remediation of souring of oil, gas and coalbed geological reservoirs comprising adding to the water used in a hydrofracturing or flooding operation an effective amount of virulent bacteriophage derived from non-lysogenic bacteria and specific for target bacteria, the target bacteria comprising acid producing bacteria and sulfate reducing bacteria.
2. The process of claim 1 wherein the virulent bacteriophage comprises a multi-panel of virulent bacteriophages, each having at least two bacteriophages virulent for each species of target bacteria.
3. The process of claim 1 wherein the effective amount of bacteriophage comprise bacteriophage indigenous to the general location where it is to be applied to remediate reservoir souring.
4. The process of claim 1 wherein a solution of bacteriophage has a concentration of bacteriophage of about 1×10 7 to 1×10 10 pfu/ml.
5. The process of claim 1 wherein target bacteria comprise sulfate reducing bacteria, sulfuroxidizing bacteria capable of generating sulfuric acid, and iron-oxidizing bacteria.
6. The process of claim 1 comprising:
providing a water pond or storage tank,
adding a solution of bacteriophages virulent for target bacteria to the pond or storage tank solution to at least 1×10 5 pfu/ml, and
injecting an effective amount of the resulting solution into the reservoir.
7. The process of claim 6 wherein the target bacteria comprise sulfur reducing bacteria.