|Oil shale bed.|
Chevron Corporation and Los Alamos National Laboratory (LANL) have created a joint research project to improve the recovery of hydrocarbons trapped in oil shales and slow-flowing oil formations.
The goal of the Chevron-Los Alamos collaboration is to develop an environmentally responsible and commercially viable process to recover crude oil and natural gas from western US oil shales. The joint research and development effort will focus on oil shale formations in the Piceance Basin in Colorado.
The Chevron-LANL work will include reservoir simulation and modeling, as well as experimental validation of new recovery techniques, including a form of in-situ production that has the potential to mitigate greenhouse gas emissions via the capture and re-use of combustion gases.
|Chevron Shale’s concept for pilot oil shale RD&D. Click to enlarge.|
Chevron Shale Oil Company’s oil shale development proposal is one of the five judged eligible for further consideration and analysis by the Bureau of Land Management (BLM) under the National Environmental Policy Act (NEPA). The other four are one from EGL Resources, Inc. and three from Shell Frontier.
Chevron plans to use the 160-acre lease in the RD&D program to evaluate the technologies developed through its alliance with Los Alamos, subject both to approval from the bureau and the success of the research program.
As outlined in its proposal, Chevron’s basic approach is to use conventional drilling technologies and modified fracturing techniques designed to control and contain subsurface processes within the oil-rich shale zone.
Chevron suggests that the use of conventional drilling methods for extraction would require a smaller footprint, and may therefore be less injurious to the environment, than past shale oil extraction technologies. The use of conventional drilling may also be more cost efficient and consume fewer resources since water and power requirements would be approximately equal to that of any modern oil and gas drilling operation.
After drilling, Chevron would apply a series of controlled horizontal fractures within the target interval to prepare the production zone for heating and in-situ combustion. Critical to the viability of the process is the ability to generate relative uniformity in the fractured material to yield economic quantities of shale oil when heated to the kerogen decomposition temperature. (Kerogen is the organic precursor to oil or natural gas contained in the shale.)
Chevron proposes to circulate hot CO2-rich gases through the fractured formation from well to well and then routed back to a gas generator to be reheated. This process would create the heat needed to decompose the kerogen into producible hydrocarbons.
In-situ combustion of the remaining organic matter in previously heated and depleted zones would generate the heated gases required to process successive intervals. These gases would then be pressured from the depleted zone into the newly fractured portion of the formation and the process would be repeated.
The Chevron-LANL research project will be conducted under the Strategic Alliance for Energy Solutions launched by Los Alamos and Chevron in 2004. The alliance supports Los Alamos in its mission, on behalf of the US Department of Energy, to advance the national, economic and energy security of the United States through scientific and technological innovation. It also supports Chevron’s strategy to develop innovative research and educational partnerships within the energy industry.
BLM Oil Shale RD&D documents
Environmental Assessment, Chevron Oil Shale Research, Development & Demonstration