Cement-Conveyed Technology Improves Zonal Isolation and Stimulation Efficiency

Abstract

Successful cement placement in horizontal wellbores requires solutions for several technical challenges. Zonal isolation provided by cement is considered an important factor for efficient stimulation. A cement system was designed and recently introduced in unconventional developments to mitigate hydraulic isolation challenges encountered when cementing horizontal wellbores. Herein, we disclose recent results that show the efficiency of the interactive cementing system (ICS) in both laboratory and field case studies. Specifically, decreased communication between stages and improved production compared to offsets. At the 2018 SPE Annual Technical Conference, Kolchanov et al. described the ICS improving zonal isolation in wells that would otherwise contain mud channels symptomatic of the cleaning methods used in unconventional developments (SPE-191561-MS). The scaled performance tests disclosed in that publication are further evaluated to build on the relationship between the laboratory test and realistic downhole scenarios. Literature data indicate that >30% of stages have communications with previously treated zones. The ICS was shown to eliminate interstage communication during stimulation operations when compared to conventional cement systems. To investigate the effect of the ICS on completion quality, five wells cemented with the ICS and stimulated by multistage hydraulic fracturing were compared with numerous offset wells drilled, cemented, and stimulated during the last 2 years in the same producing zone within a 10-mile radius. The early normalized production data have been analyzed, and they indicate a statistically significant increase of production for the ICS-treated wells. This shows the importance of an integrated approach in well construction process, especially for challenging horizontal wells.