摘要 :
A joint DOE-Gulf Oil Corporation, nonproducing carbon dioxide minitest was conducted in the Little Knife Field in western North Dakota. At the time of the project, the reservoir was undergoing primary depletion and had no secondar...
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A joint DOE-Gulf Oil Corporation, nonproducing carbon dioxide minitest was conducted in the Little Knife Field in western North Dakota. At the time of the project, the reservoir was undergoing primary depletion and had no secondary recovery operations underway. The five-acre inverted four-spot tested the applicability of a CO sub 2 -alternating-with-water injection process to commercially displace oil in the nonflooded Mission Canyon Formation located in the Williston Basin. The nonproducing test was evaluated using time-lapse logging and fluid sampling to monitor fluid movement as injected CO sub 2 and water displaced 41 sup 0 API oil in three observation wells which surrounded a central injector. Numerical simulation studies using the time-lapse logging data provided the basis for estimating pilot performance and evaluating a proposed expansion of the process to a 160-acre pattern. Gulf personnel are to be commended for designing and implementing a state-of-the-art, nonproducing pilot test of the CO sub 2 process. Results obtained in the pilot show an optimistic incremental recovery over waterflooding of 8.0 percent of the oil-in-place (OOIP) with an optimistic 1.0 STB of oil production estimated per 5.0 to 8.0 MSCF of injected CO sub 2 depending on exclusion or inclusion of Zone W. Assuming a more realistic 1.0 STB of oil recovered per 10.0 MSCF of injected CO sub 2 , these results still encourage the commercial application of the process to the Little Knife Field upon location of a suitable CO sub 2 source. 34 refs., 17 figs., 13 tabs. (ERA citation 11:029233)
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摘要 :
The Penn Grade Micellar Displacement Project tested the micellar/polymer flooding process in a low permeability portion of the Bradford Third Sand reservoir. This test, herein referred to as the Lawry Test, followed the successful...
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The Penn Grade Micellar Displacement Project tested the micellar/polymer flooding process in a low permeability portion of the Bradford Third Sand reservoir. This test, herein referred to as the Lawry Test, followed the successful test of the micellar/polymer flooding process in a higher permeability portion of the Bradford Third Sand reservoir (Bingham Test). The Lawry Test failed technically and economically as an oil recovery process. Total oil recovery amounted to about 5.2% of the oil-in-place at the time of micellar injection. Project failure did not appear to be the reusult of poor operational practice. Project participants recognized the difficulty of applying the micellar/polymer process in such a low permeability reservoir at the initiation of the project. Nevertheless, the large reserve of oil trapped within the low permeability portions of the Bradford Field made the project attractive. There appeared to be three major reasons for project failure: (1) reservoir heterogeneity; (2) adverse ion exchange phenomena; and (3) high sulfonate loss. Data from Phase I testing, injection well tracer surveys, injection well logging, produced chloride concentrations and the Phase II evaluation well confirmed that only a small portion of the Lawry pilot was contacted by injected fluids. Produced salinity and hardness levels suggested the occurrence of adverse ion exchange phenomena. Adverse ion exchange behavior would be expected to have resulted in severe sulfonate loss, and low oil recovery. Additional data are needed to confirm this conclusion. In addition, injectivity was low throughout the project. In the absence of the above problems, it is likely that the process would not be practical in areas typical of Lawry because of low injectivity. 10 references, 12 figures, 12 tables. (ERA citation 09:049446)
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