Microbially enhanced thermal oil recovery
Assignee9668241 Canada Inc.
InventorsCasey Hubert, Milovan Fustic
Life of this patent
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Abstract
A method and a system for recovering oil from currently inaccessible oil containing geological units by activating the deep biosphere microbial seed bank. Nutrient and thermal enhancement of microorganisms in oil containing geological units allows for stimulation of inactive and/or dormant microorganisms such that they proliferate and produce gas. The oil viscosity that is decreased by heat, along with the gas pressure produced by activated microbes which allows previously inaccessible oil to flow toward production wells.
Claims19
A method for oil recovery in a subsurface of an oil reservoir, the method comprising the steps of:
- retrieving a test sample from a microbial seed bank located in the subsurface of the oil reservoir;
- conducting testing of the test sample to identify at least one in situ dormant microorganism;
- identifying high temperature conditions for optimal microbial gas production based on a physiology of the at least one in situ dormant microorganism;
- causing a change in temperature of the subsurface, wherein after the change in temperature, the temperature of the subsurface is one of:
- between above an in situ temperature and below an upper limit for microbial life;
- and
- between below the in situ temperature and above a lower limit for microbial life;
- to thereby stimulate activity of the at least one in situ dormant microorganism from the microbial seed bank to thereby produce a gas pressure within the subsurface;
- and
- utilizing the gas pressure and/or volume in recovery of subsurface oil through a production recovery well,
- wherein said oil reservoir has previously been subject to hydraulic fracturing.
A method for oil recovery in a subsurface of an oil reservoir, the method comprising steps of:
- (a) utilizing at least one injection well within the subsurface;
- (b) causing a change in a temperature of the subsurface, wherein after the change in temperature, the temperature is within a range suitable for microbial life, the change in the temperature stimulating activity of at least one in situ dormant microorganism located in the subsurface, the activity producing a change in conditions within the subsurface;
- and
- (c) utilizing the change in conditions in recovery of subsurface oil through a production recovery well, the change in conditions being at least one of:
- a change in pressure conditions or a change in gas volume conditions,
- wherein said oil reservoir has previously been subject to hydraulic fracturing,
- wherein, prior to step (b), high temperature conditions for optimal microbial gas production based on a physiology of seed bank microorganisms are identified.
Dependencies are inferred from the claim text.