Wadhah Al-Tailji is a technical manager at StrataGen, where he advises on hydraulic fracturing completion design and optimization. His professional areas of interest include proppant transport and improving propped fracture effectiveness. He holds BS and MS degrees in petroleum engineering from the New Mexico Institute of Mining and Technology, and served as an SPE Distinguished Lecturer during 2017-2018. |
Cramer, D., Friehauf, K., Roberts, G., and Whittaker, J. February 2019, SPE Hydraulic Fracturing Technology Conference and Exhibition Comments This paper investigates the impacts of perforation entry on fluid and proppant distribution through multiple perforation clusters in cased-and-cemented horizontal wellbores. This study incorporated the use of rate step-down tests, distributed acoustic sensing (DAS), and videographic recordings captured by a camera tool deployed via e-coil and e-line. Ruler markings were engraved on the insides of the centralizer bow springs for scale on the video images. Measurements of individual perforation dimensions were extracted from the video images to determine the degree of perforation erosion that occurs after injection of slurries with proppant through the perforations, which were then correlated with relative position in a completion interval, which were compared with step-down analyses and DAS data. The authors found good agreement between the different diagnostic methods and that there was a general bias of larger eroded perforation diameters toward the heel-most clusters (consistent with other studies). Improved Completion Economics Through Real-time, Fiber Optic Stimulation Monitoring Stark, P.F., Bohrer, N.C., Kemner, T.T., Magness, J., Shea, A., and Ross, K. February 2019, SPE Hydraulic Fracturing Technology Conference and Exhibition Comments This paper summarizes the results of an Eagle Ford field experiment utilizing DAS real-time fiber-optic monitoring to improve fluid and proppant distribution through multiple perforation clusters. A novel technique of portraying the raw DAS data as relative slurry and proppant flow rates per cluster, generated by an empirical flow model, are displayed on site and remotely in real time which were used evaluate completion effectiveness and make design adjustments. A 12-cluster completion with extreme limited perforating was found to be more effective at fluid and proppant distribution than the original eight-cluster design, which also resulted in significant cost savings in wireline plug-and-perf staging and stimulation costs. The paper ends with indicating that further enhancements to this technique have been implemented since the study project described in the paper, so it will be interesting to see the evolution of this technique in future publications. Proppant Transport and Behavior in Horizontal Wellbores Using Low Viscosity Fluids Ahmad, F.A. and Miskimins, J.L. February 2019, SPE Hydraulic Fracturing Technology Conference and Exhibition Comments This paper presents the results from laboratory tests of thin fluid proppant transport in horizontal pipe. The test apparatus contained three perforation clusters, and experiments were conducted with varying fluid flow rates, proppant concentrations, proppant mesh size, and proppant density (silica sand and ultra-lightweight ceramic), to observe fluid and proppant exit rates and volumes out of each cluster and proppant settling in the pipe sections between clusters. The experiment results showed that although the flow distribution of the fluid through the three clusters was roughly equal, proppant mass exiting the clusters can vary between the clusters. Higher-density proppants at lower flow rates exhibited higher proppant exit rates in the heel-side clusters and settling was observed toward the toe-side cluster, which may be an explanation for heel bias observed in field experiments. Some papers previously postulated proppant settling in pipe as a potential reason for heel bias (such as Somanchi et al, 2016 URTeC paper 2458389). |