Abstract:
Normal-pressure shale reservoirs in Wulong Block have low energy and production, and suffer from difficulties in beneficial development. For this reason, a low-cost fracturing technology was studied for its development. Considering difficulties of fracturing stimulation in Wulong Block, induced stress calculation, fracture simulation, and fracturing cost comparisons were carried out. This allowed the fracturing stage length, number of clusters, and operation parameters to be optimized. Further, the fracturing materials and equipment were chosen. A new fracturing technology was thereby developed, involving a short fracturing stage length, a single-cluster sleeve, low-viscosity slick water, low-cost quartz sand, continuous sand addition at a high proppant concentration, which was then applied in the field test on Well A in Wulong Block. Through the application of the unlimited sliding sleeve completion and the real-time adjustment of on-site fracturing parameters, the production of Well A after fracturing was comparable to that of the fracturing well on the same platform with fracturing parameters of a medium fracturing stage length, tight cluster spacing, and ceramic proppants. In this study, the fracturing cost was reduced by 52.8%, and the fracturing performance sped up to 8 stages per day. The low-cost fracturing technology has provided technical reference for the beneficial development of normal-pressure shale gas in Wulong Block.