摘要：Tight sandstone reservoirs are characterized by low porosity and low permeability, and commercial production cannot be obtained with conventional ining methods. Hydraulic fracturing technology is an important measure to realize the commercial de- velopment of tight sandstone gas reservoirs. The core technology of fracturing is fracturing fluid sys- tem and hydraulic fracturing process, and the ulti- mate goal of fracturing is to form a high-conductivitysupporting fracture zone in the reservoir. In this pa- per, taking the Upper Paleozoic tight sandstone gas reservoir in the Shenfu area, eastern Ordos Basin, China as an example, and a low-cost fracturing fluid system was designed. Combined with multi-stage sand laying fracturing technology, the optimization of tight gas reservoir fracturing is realized. The re-search results show that, in view of the difference in the shale content of the reservoir, the fracturing fluid of the combination of inorganic salt and organic anti swelling agent is designed, and its anti-swelling rate is 91.6%. Comprehensive optimization research of biological enzymes, clay stabilizers, and drainageaids, the recovery rate of core permeability afterfracturing has been increased from 75% to 84%. The fracturing fluid system can be compatible with for- mation water with a salinity of 105 mg/L, and has excellent sand carrying capacity. The retention of fracturing fluid in the reservoir will cause a water lock effect, and the addition of a drainage aid can re- duce the capillary resistance of the breaker fluid from the pores. Therefore, the surface tension of thepreferred high-efficiency drainage aid at a dosage of 0.5% is lower than 20 mN/m, and the capillary re- sistance of the fracturing fluid is reduced by 72% when the fracturing fluid flows back. The optimiza- tion of multi-stage sand laying fracturing technology shows that the fracturing construction displacement is 3-5 m3/min, the proppant scale is between 30-45 m3, the fracturing fracture length is 200 m, and the proppant concentration is 3.5 kg/m2. This technol- ogy can significantly improve the success rate of fracturing construction. After adopting multi-stage sand laying fracturing technology, the probability of sand plugging is 0%, and the success rate of fractur- ing test is 100%.
关键词：Shenfu area;tight gas reservoir;fracturing;fracturing fluid;multi-stage sand laying fracturing technology
