Carbon dioxide energy storage and enhanced oil recovery

Abstract

The present invention is a method and apparatus for the subsurface storage of carbon dioxide in reservoir formations, to provide energy storage for electrical load balancing, and to enable the enhanced recovery of hydrocarbon fluids from the subsurface formations by gravity drainage. Multiple propped vertical inclusions are propagated into hydrocarbon fluid bearing reservoir formations at various vertical depths from well casings. Carbon dioxide is injected and stored in the formations. At off-peak power demand periods, carbon dioxide is pumped by a pump / turbine from the low energy formation into a deeper high energy formation, and at peak power demand periods the carbon dioxide is released from the high energy formation and flows to the low energy formation, driving the pump / turbine to generate electricity. Hydrocarbon fluids are produced from the formations depending on the formation conditions. Additional carbon dioxide is injected into the system as hydrocarbon fluids are extracted.

Description

CLAIM OF PRIORITY[0001]This application claims priority from U.S. Provisional Patent Application No. 61 / 900,612 filed on Nov. 6, 2013, which is relied upon and incorporated herein in its entirety by reference.TECHNICAL FIELD[0002]The present invention generally relates to the geological storage of carbon dioxide, the closed cycling of carbon dioxide from one reservoir formation to another for energy storage to balance electrical loads, and the subsequent enhanced recovery of petroleum fluids (oil) from the subsurface formation by gravity drainage.BACKGROUND OF THE INVENTION[0003]Carbon capture and storage in geological formations is a much focused research area due to the greenhouse gas effects of releasing carbon dioxide to the atmosphere. The carbon dioxide can be stored in geological formations in the form of a trap, the trap being a depleted oil and gas field or a saline aquifer. The cost of such storage is high, but in the case of natural gas reservoirs containing high levels o...

AI Technical Summary

Benefits of technology

The invention is a method and device for storing carbon dioxide underground to provide energy storage for electrical load balancing, and to improve the recovery of petroleum fluids from underground formations through gravity drainage. The method involves injecting carbon dioxide into a high energy reservoir formation and a shallower depleted reservoir formation, and the carbon dioxide interacts with the oil and gas in the formations to increase the production of petroleum fluids. The invention enables more efficient and economical energy storage, and reduces environmental impact.

Problems solved by technology

In the case of carbon capture from coal fire power plants, the cost of such carbon dioxide storage could be excessive for the operation of the power plant.

Gravity drainage, however, is not applicable to many reservoirs due to the reservoir's low vertical permeability and the low mobility of the oil.

Reservoirs with moderate to low vertical permeability are not suitable for gravity drainage because the recovery mechanism is extremely slow in these types of formations.

Techniques used in hard, brittle rock to form fractures therein are typically not applicable to ductile formations comprising unconsolidated, weakly cemented sediments.

The methods disclosed above find especially beneficial application in ductile rock formations made up of unconsolidated or weakly cemented sediments, in which obtaining directional or geometric control over inclusions as they are being formed is typically very difficult.

Apparent cohesion is generally such a small component of strength that it cannot be effectively measured for strong rocks, and only becomes apparent when testing very weakly cemented sediments.

Ductile frictional materials fail under shear stress and consume energy due to frictional sliding, rotation, and displacement.

Such a process, however, has not been duplicated in the laboratory or in shallow field trials.

Linear elastic fracture mechanics is not generally applicable to the behavior of weakly cemented sediments.

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