特高含水率油层聚合物驱油试验效果评价

本文介绍了在大庆油田萨北厚层试验区葡Ⅰ1-3层进行聚合物驱油矿场试验的方案及其实施情况,用多种方法评价了厚油层达到特高含水率以后聚合物驱油的效果。在本次试验中,聚合物驱油使特高含水率油层的采收率提高了4％以上。

PILOT TEST ON POLYMER FLOODING OF THICK RESERVOIR WITH EXTREMELY HIGH WATER CONTENT IN NORTH OF SAERTU OIL FIELD, DAQING: RESULTS EVALUATION

This polymer flooding pilot test is being performed at an experimental base of area 0.5km~2 with 9 producing and 4 water-injecting wells which are spaced according to a five point scheme. Seven tests of various purposes had been conducted here since 1975 and at the beginning of the pilot 55% of OOIP had been recovered, 3.01 PV of water injected for flooding the reservoir, water content of produced fluid were as high as 94.1% at whole base and 99% in the central well. From Feb 10, 1988 to sept 4, 1990, 350 t polymer (145 t 1135L, Allied Colloid, UK, and 205 t EPA, Tongde Chemical Plant, Dalian, P. R. of China) in solution of 0.345 PV was injected in 3 slugs of different concentrations, followed by continued water flood until Jan 1994 to finish the pilot. Up to oct 1991, when 0.2 PV water has been injected after the polymer slugs, an oil recovery enhancement of 3.05% OOIP is obtained, or 96.6 t oil is recovered by every ton polymer injected in the area of the base. The later will be 183 t oil per one ton polymer if the oil production increasement of benefited wells outside the base is considered. Other results are the decrease in water content of produced fluid, improvements in efficiency of water utilization and in sweeping efficiency of the reservoir in vertical direction