Improving Proppant Transport in Slickwater Fluids Using Newly Developed Viscosifier

Hydraulic fracturing techniques have played a major role in transforming the United States petroleum industry. As the industry has sought to reduce costs and improve efficiency in recent years, there has been considerable interest in a 'less is more' approach as producers seek to maintain or improve production using fewer materials.;Fracture fluids serve an important function as the means for both creating fractures and transporting proppant, material which is used to hold fractures open after treatment. It is understood that holding more of a fracture open should improve production from the fracture, and that moving proppant further into a fracture can achieve that end. This could be accomplished with a highly viscous cross-linked fluid; however, this method relies on large amounts of polymer and can incur large costs. The alternative of a low-cost slickwater fluid, consisting of little more than water and a friction reducer, would not be able to transport proppant as effectively, as its low viscosity changes the mechanism by which proppant travels. However, the precise role of viscosity in slickwater fluids has not been thoroughly examined, and even small increases in its value could have significant impacts on its ability to move proppant into a fracture, rendering these fluids as viable low-cost alternatives to cross-linked fluids with similar performance. This work examines the use of newly developed viscosifiers in improving proppant transport. New fracture fluid formulations were prepared using these viscosifiers to exhibit higher viscosities than typical slickwater fluids, though not so much as to change the means of proppant transport. These new fluids were then run in a specialized facility to directly observe their impact on proppant movement. Finally, the use of dimensionless groups is employed to extrapolate the experimental results to actual fracture conditions. Separately, the differential pressure of these fluids was observed under different flow conditions to assess their viability as slickwater friction reducers, ensuring adequate friction reduction performance in addition to improved proppant transport characteristics.