Flowback aid surfactants are key components for optimal water recovery after a fracturing treatment. However, comprehensive guidelines and discovery workflows for selecting an optimal flowback aid are lacking. A suite of carefully designed high-throughput screening tests coupled with industry performance tests was developed and applied to over 50 surfactants representing 12 chemical classes to create a portfolio of formation-specific flowback aids. Experiments were carried out in a two-stage approach that focuses both on intrinsic surfactant properties and on interactions with the reservoir environment. In the first stage, promising surfactant candidates were selected using high-throughput testing of surface tension, critical micelle concentration, cloud point, mineral adsorption, emulsification, and heat-aged stability. In the second stage, efficacy of surfactant candidates was assessed by testing fracturing fluid cleanup from selected shale matrices. We observed trends in critical performance parameters with simple engineering design criteria, such as hydrophile/lipophile balance (HLB), or field conditions, such as salinity. All surfactants tested showed efficient surface tension reduction and minimal effect of salinity on surface tension. Critical micelle concentrations, however, decreased with increasing salinity, and the effect was more pronounced for surfactants with a greater HLB number. Further candidate differentiation for the optimal surfactant package was achieved by testing adsorption on shale minerals. The validity of the approach was confirmed by testing cleanup from sand and shale matrices with final product candidates.
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