Research On The Fracturing Fluid System Applied In The Strong Water Sensitive Reservoirs Of Gars Oil Field

Hydraulic fracturing technology is an important measure that boosts production of oil and gas field. With the emergence of a series of the strong water sensitive and low pressured reservoirs, the fracturing fluids which are suit for these reservoirs are in great urgency. Both properties and existing problems of the conventional fracturing fluids were described in this paper, and a new water-in-oil emulsion fracturing fluid was developed according to the properties of strong water sensitive and low pressured reservoirs of Gars oil field, Qinghai Province.In terms of the water-in-oil emulsion theory, emulsion materials, emulsion methods, main additives and the volume ratio of oil and water were selected and then a basic formulation of the water-in-oil emulsion fracturing fluid was screened out. On the base of it above, the optimal formulation was optimized following the properties of reservoirs of Gars oil field, Qinghai Province and the performance of it was evaluated referring to SY/T5107-95. In the end of this paper, a idea of job design and technologies of fracturing optimize of the water-in-oil emulsion fracturing fluid were put forward. All the test results showed that this water-in-oil emulsion fracturing fluid posseses such advantages as good themal stability, good shearing stability, low filter loss, low hurt, good restrainting the inflation of clay material, easy breaking of emulsion and flowback and so on, and then it can replace the conventional oil base gel and be used in fracturing the low pressured and strong water sensitive reservoirs of Gars oil field, Qinghai Province.