Study on hot fracturing fluid technology and its application

Over 60% of the oil production is high viscous crude in Liaohe Oilfield, and the content of wax and gelling asphalt is also high. The precipitation of wax and gelling asphalt during fracturing causes the blocking of throats and this seriously impacts the effect of fracturing stimulation. The hot fracturing fluid technology is developed and applied, by raising the fracturing fluid temperature so that its temperature is higher than the wax precipitation point, and this minimizes the formation damage because of cold fracturing fluid. The composition of the hot fracturing fluid is optimized, which consists of base fluid and cross-linking fluid. The base fluid is made up of 1. 4%-1. 8% of concentrated fluid guar gum, 0. 2% of FR-Cl/LH- I demulsifier, 0. 05% of bactericidal agent and defoaming agent, and 0. 02%-0. 03% of pH value adjusting agent. The cross-linking fluid is consisted of 10%-15%of high temperature delayed crosslinker and 1%-2% of gel breaker, the cross-linking ratio is 100/(2-3). This technology has been used in 16 wells for viscous crude reservoir fracturing, and a remarkable production rate improvement of 12. 75 t/d has been achieved.