Improved efficiency of miscible CO{sub 2} floods and enhanced prospects for CO{sub 2} flooding heterogeneous reservoirs. Quarterly technical progress report, April 1, 1996--June 30, 1996

Progress has been made in each of the three project areas during this quarter. Each quarter we are highlighting one project area. This quarter, Task 2 is highlighted with expanded details. Significant progress has been made this quarter in testing the functionalities of the foam-durability apparatus for assessment of foam properties at reservoir conditions. Another surfactant, Alipal{reg_sign} CD-128 at a concentration of 1000 ppm, was used for core flooding experiments. The foam mobility data showed a significant reduction of CO{sub 2} mobility and a favorable mobility dependence on rock permeability. Two slim tube test series and continuous phase equilibrium were done to examine the effects of pressure, temperature, and oil composition on oil displacement efficiency. A new series of core foam tests were completed to study the effects of flow rate, CO{sub 2} fraction (foam) quality, and rock permeability on foam-flow behavior. We are in the process of moving the foam reservoir simulator MASTER from a workstation to a Pentium PC environment and test MASTER on a 166 MHz Pentium PC. IFT of CO{sub 2}/crude oil has been measured using our pendant drop measurement system at 138{degrees}F and pressures from 850 psig to 2200 psig. The CO{sub 2} gravity drainage experiment that is in progress using a 50md Berea core at 138{degrees}F and pressures from 1700 to 2000 psig has reached 48% oil recovery and is continuing to increase. The mathematical model developed previously matches the experimental response accurately