The U.S. Department of Energy is helping fund a research program aimed at finding cheaper methods to dispose of drill cuttings and fluids from offshore operations.
Westport Technology Center (WTC), Houston, has received a $293,000 grant from DOE's fossil energy research program and more than $91,000 in private sector funding for laboratory investigations to determine if drilling wastes can be injected safely into unconsolidated sand formations onshore and offshore.
DOE said the key will be to ensure that the injection processes don't create fractures in the formations and allow the waste materials to escape.
WTC, with the aid of Stanford University's Rock Physics and Borehole Geophysics Group, will study deformation-the effects of stress on a rock formation-on rock samples prepared in the laboratory that simulate the grain sizes and sand/clay mixtures of the candidate reservoirs.
WTC will use its rock testing system to measure reaction to stress and strain in the samples. Both dry samples and samples saturated with brine, oil, and other fluids will be tested.
The Stanford group will investigate the primary mechanisms controlling deformation, including the ways sand and clay mixtures react in response to changing stress, pressure, and movement in the formation.
DOE said the research will develop a computer model of the deformation process, a model that producers can use to design environmentally acceptable injection strategies that meet the needs of individual production operations.
Applications
"Results from the project could play an especially significant role in future oil and gas operations in the Gulf of Mexico" said DOE. "In contrast with many onshore drilling operations where water-based drilling fluids can be used and disposed of inexpensively, certain formations in the gulf can be damaged by water-based fluids.
"Drilling wells into these formations requires oil-based or expensive synthetic fluids. Environmental regulations ban the disposal of these fluids into the ocean. If techniques can be developed to inject these wastes into underground formations, rather than the costly alternative of barging them, more offshore oil and gas reservoirs could become economically attractive," DOE said.
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