Research On Multi-slot Staged Fracturing Technology In Horizontal Well Sections

Nowadays unconventional gas resources including tight gas and shale gas become increasingly important, horizontal well staged fracturing technology is the key to the effective development of unconventional reservoirs technology. The research on this technology is of great significance. In the horizontal heterogeneity and wellbore under complex conditions, conventional horizontal well staged fracturing technology can not fully open the reservoir. According to the multiple crack initiation mechanism and the single point initiation mechanism in the horizontal well multi crack condition, formed the method of selecting well and selecting layer.Temporary plugging material was developed, formed the temporary plugging materials to delivery and fracturing fluid system supporting technology. Field application results showed, In the case of strong heterogeneity and well bore, the technology solved the problem of the opening rate of the reservoir. It supported the efficient development of shale and other unconventional reservoirs. Through the research the following main results and understanding was obtained:(1) Based on the heterogeneity of reservoir and the heterogeneity of stress, the method of selecting well and layer selection is formed. The method was feasible.(2) Two types of degradable temporary plugging agents were developed.they were Water soluble type and Temperature controlled type. They had nice properties of High pressure resistance and high blocking pressure.(3) Formed a set of horizontal well section of the multi-seam sectional fracturing technology-Temporary plugging agent delivery technology and Fracturing fluid system, to meet the needs of reservoir reconstruction.(4) The technology was adapted to the shale gas reservoir reconstruction, and the improvement effect was remarkable.The technology broke through the bottleneck of the conventional horizontal well sectional fracturing technology. It had important significance for the development of unconventional resources such as shale gas.