Fracturing Fluid Comprised of Components Sourced Solely from the Food Industry Provides Superior Proppant Transport

The industry is seeing significant pressure from regulatory bodies concerning the chemicals that comprise typical fracturing fluids. It has long been the belief of the industry that to obtain the best performance of a fracturing fluid, it is necessary to use certain chemicals in fracturing-fluid formulations. However, this paper clearly illustrates that a fluid comprised solely of components sourced from the food industry can excel in maintaining proppant-transport performance. This paper focuses on the proppant transport of a fracturing fluid that is comprised solely of components sourced from the food industry and approved for direct addition to foods as governed by the Code of Federal Regulations Title 21 (CRF 21). The proppant-transport capabilities of this fluid are compared to a borate-crosslinked galactomannan, a viscoelasticsurfactant (VES) fluid, and a linear-gelled system. The results illustrate that proppant-transport performance does not need to be sacrificed when using a fluid system comprised of components sourced from the food industry. The ability to carry proppant into the fracture is one of the most fundamental attributes necessary for a successful fracturing fluid. This paper provides an evaluation of four types of fluids currently used as gelled fracturing fluids, employing five different methods to measure their ability to transport and support proppant. The methods used in the evaluation include traditional steady-shear viscosity, small-amplitude oscillation rheology, flow-through-a-slot model, a slurry viscometer, and static settling results. The results show clearly that the testing methods and protocols do not necessarily agree on the best performance of a fluid system; a comprehensive examination of the limitations and benefits of each are examined. Some of the gels tested showed good proppant support under static conditions, while others showed good transport under flow conditions. The crosslinked gel that was sourced solely from the food industry showed a dramatic difference in that it was able to support proppant under static- and dynamic-shear conditions, leading to superior proppant-transport performance using the five test methods.

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