Staged chemical water plugging for horizontal wells with screen completions for heavy oil reservoirs in Liaohe Oilfield

At present, due to invasion of edge water and bottom water, some horizontal wells with screen completion for heavy oil reservoirs in Liaohe Oilfield are producing with high watercut, which severely affects their productivity; for this reason, research on staged chemical water plugging technique has been conducted, and key tools and water plugging materials have been developed like fishable bridge plug in horizontal wells, high temperature resistance plugging agent for horizontal wells, liquid plug for horizontal wells, etc., and the staged chemical water plugging for horizontal wells has been developed, which can realize accurate water plugging at any point in horizontal section, and water plugging accuracy can be up to 2 m. This technique has been used for 19 well-times since 2010 on such blocks as Xinhai Block 27, Du Block 84, Gao Block 246 and Leng Block 41 in Liaohe Oilfield. By April of 2014, accumulated increase in oil production was 8 173 t and water reduction was 9.69×104 m3, so the tests were proved very effective. Field tests show that staged chemical water plugging technique for horizontal wells can meet the requirement of water plugging in horizontal wells and has significant promotion and application value. At present, the effective period of staged chemical water plugging is about 8 months in general, so how to improve the effective period of water plugging remains to be tackled in further research.