The Study On Improvement Of Oil Wells Plugging Technology In Suijing Oilfield

For the flooded wells,the main reason of Chang6reservoir in the second district of Dalugouin Suijing Oilfield and Chang4+5reservoir in the district of Baiyushan are all that water isbeing invaded along the high permeability layer (or cracks)wells.So that the low-permeabilityreservoir of high oil saturation is not disposable,and it is difficult to develop oilfield, moistureis rapidly rising. To solve this problem, development and preference of blocking agent canplugging high-permeability layer (or cracks), improve sweep efficiency of water and reducemoisture of oil wells. At last, to enhanced oil recovery could be achieved.By analysing and studying Chang6reservoir in the second district of Dalugou in SuijingOilfield and Chang4+5reservoir in the district of Baiyushan in detail, for their reservoirproperties and reservoir characteristics, this thesis had evaluated the potential harm factorsof reservoir, the extent and scope of the damage and the conflict of development. And basedon the study，the thesis had evaluated and analysed5existing blocking agent system whichwere fractured blocking agent system, composite blocking agent system, strong gel system,weak gel system and underground crosslinking blocking agent system by various methods oftest and means of evaluation. So that four blocking agent system which comprehensiveperformance were better had been picked up and these four blocking agent system had beenoptimized with orthogonal experiment. When the fractured blocking agent system had beeninjected0.05PV, strong gel system had been injected0.04PV, weak gel system had beeninjected0.35PV and underground crosslinking blocking agent system had been injected0.05PV, the effect of plugging was best.In2012~2013，about10oil wells had been plugginged at Chang6reservoir in the seconddistrict of Dalugou in Suijing Oilfield and Chang4+5reservoir in the districrt of Baiyushan.After the measures, the average daily growth of single-well oil had been0.8ton, and thecumulative average growth of single-well oil had been342ton. The efficiency of measureshad been100%, which the effect of water plugging and growth of oil was obvious.