In 2014, the oil and gas industry will celebrate 65 years of hydraulic fracturing. Over the years, the number of stimulation treatments in Russia has grown. In the early 1960s, for example, 1,500 jobs were performed per year; in 2012, more than 39,500 operations were performed. This increase is the result of the demand for effective development and redevelopment of low-permeability formations and mature oil fields. Hydraulic fracturing effectiveness has become a key focus for Russian oil-producing companies over the past decade. Optimization of the fracturing fluid parameters is one of the fundamental elements of the whole reservoir stimulation process. Six main milestones in the evolution of fracturing fluids in Russia over the past 10 years can be identified: 1) the revision of the requirements set for quality of fracturing fluids which included the introduction of the so-called "shear stress" test and stability tests for pad, middle, and last proppant stages; 2) designing fracturing fluids for stimulation treatments using large-size proppants; 3) optimization of fracturing fluids on the basis of Cenoman water; 4) improvement of retained fracture conductivity by minimizing polymer loading and optimizing breaker concentration without sacrificing fracturing fluid performance, with documented cases of a 15 to 20 % polymer reduction leading to a 100 to 150 increase in productivity index; 5) simplification of fracturing fluid designs by the introduction of a self-buffering crosslinker, which allowed to decrease a number of fracturing fluid additives by half; and 6) development and implementation of the dry version of the borate-based crosslinker to address Russian cold weather conditions, with associated changes in logistics and the development of methods for maintaining high fluid efficiency.
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