The Experiment Of Flowing Gel Carried On The Fault Block Yan 50 Of Huabei Oil Field

Most waterflooding reservoirs has come into the later development period recently. It is a common problem that waterflooding exhihat lower sweep efficiency, leaving high viscosity. Water shut-off and profile control is one of the important ways to improve waterflooding development.The fault block Yan 50 in Huabei Oilfield belongs to low permeability sandstone porous media. Its geological reserve is 1980,000 tons and recoverable reserve is 495,000 tons. The fault block Yan 50 in Huabei Oilfield was been explored formally in January 1987. The structural heterogeneity is very remarkable in inner-layer and interlayer of the fault block Yan 50, leading to waterflooding contradiction. The withdraw quantity have been taking 17.08% of geological reserves and 68.32% of the recoverable reserves by Feburary 2010. Howerver, there are many obstacles exsiting in present block production, such as low production rate, low level of recovery,high water content, remarkable contradiction between inner-layer and interlayer, great difficulty in hierarchical goverenance, flat contradiction, poor waterflooding efficiency, poor condition in properties of matter in replacement level, difficult reformation, poor economic efficiency, poor technical condition of underground oil and water wells. In order to further improve the recovery development performance, the study of Movable gel deep profile carried out in the fault block Yan 50. Polymer, crosslinking retardants (JL-1, JL-2), stabilizer (WD) and additives (TJ) are chosen and indicators of the polymer are measured in this study. By the screening test of flooding agent, it is shown that, the effect of expanded profile TP-3 is better. Further optimization and shutoff test of gel determines the theoretical practicability of movable gel drive technology to the fault block Yan 50. After site waterflooding, the amount of fluid in block decreased, water droped, oil production increased, daily oil production significantly increased, water content decreased, and the great effect continued. With reference to the current production of the fault block Yan 50, it is expected that the incremental oil of movable gel slug flooding is 1500t this year. The economic benefits can achieve 18.0292t per yuan. The input-output ratio is 1:2.9, which proves the feasibility of movable gel profile technology to the fault block Yan 50 .The result of prediction and evaluation methods of movable gel deep profile can meet the needs of on-site track evaluation of flooding better; It has some guiding significance to further improve the effect of deep flooding by movable gel profile system in the fault block Yan 50.