A Case Study of Boron Crosslinked Fracturing Fluid in Ultra-Deep Wall

Abstract

Abstract The ultra-deep well has a number of characteristics such as high pipeline frictional resistance, high pump pressure in operation, single method for feed flow, high requirements on properties of fracturing fluid and proppant, difficult operation and high cost and investment risk. Fracturing fluid holds the technical key to fracturing operation of a ultra-deep well. As for the characteristics of the ultra-deep, high-temperature, low-permeability and water-injection well in Tarim's DH oilfields, this paper is focused on the properties of fracturing fluid, optimum selection of the additive for organic boron crosslinked hydroxypropyl guar gel (HPG) fracturing fluid and its formulation system including thickener, crosslinker, gel breaker, cleanup additive, fluid loss additive and clay stabilizer, which are suitable for the ultra-deep well in Tarim, presentation on application of fracturing fluid for the high-temperature deep well in Tarim, and analysis and discussion of a number of features of fracturing fluid, such as controlled delayed crosslingking, reduction of frictional resistance, optimization of formula, improvement of rheological property and low damage. The field application indicates that the organic boron crosslinked fracturing fluid is possessed of low frictional resistance, good rheological property, strong sand-carrying capacity, high gel breaking ability and low damage, satisfying the requirements on the fracturing operation for the wells with a depth exceeding 5850 meters.