Green house gas has become an escalating concern in the environment and is believed to be contributing to uncharacteristic weather patterns and temperature fluctuations.
The anthromorphic sources of carbon dioxide are largely from industrial and automobile use. In terms of the industrial source, power generation plants factor heavily into the equation. As is typical, North American plants employ coal, natural gas, fuel oil, inter alia to create high pressure steam which is then used to drive steam turbines or used in diesel and gas turbine engines directly for electric power production. This, of course, creates carbon dioxide emissions, exacerbating the emissions problem.
A number of studies and attempts have been recently developed to take advantage of the volumes of carbon dioxide for enhanced oil and gas recovery in subterranean formations. It is well known that such formations, despite having been previously produced to the most economically feasible extent still contain vast reserves of oil and gas. Flue gas injection has now provided an economically viable avenue to continue to produce from the once produced formations. As an attendant feature, carbon dioxide can be sequestered in the formation thus eliminating handling concerns and ensuring compliance with the stringent requirements of the Kyoto accord.
Enhanced hydrocarbon recovery processes use miscible and immiscible gases such as natural gas, natural gas liquids, carbon dioxide, nitrogen, or combustion flue gases that maintain pressure, repressurize or expand in a reservoir to push additional oil or natural gas to the wellbore, or use the same or other gases to dissolve in the oil to lower its viscosity and increase its flow rate.
Capture and permanent storage of carbon dioxide in geologic formations has become an increasingly popular option for sequestering carbon dioxide emissions from industrial processes and coal-fired power generation. The U.S. Government is currently developing policies to encourage geologic sequestration with the view of long-term emission reduction.
The costs related to capture of carbon dioxide from power plants, and high-purity carbon dioxide sources is high at between $20 to $200 USD per metric ton of carbon dioxide emissions. Capturing and sequestering 90 percent of the carbon dioxide from a new power plant in the United States is estimated to add $0.02 per kilowatt-hour to the cost of electricity, with 75 to 80 percent of the cost for the capture, treatment and injection. Considering that capture technology is a critical aspect of plant design, installing capture technology at existing facilities presents very high costs. The present invention not only addresses capture, but further results in economic recovery of previously uneconomically recoverable hydrocarbons and provides excess usable energy.
USPTO Backgrounds
USPTO Backgrounds