Numerical Simulation of Fishbone Flexible Pipes in Fractured Vuggy Carbonate Reservoirs

The development of fractured vuggy carbonate reservoirs in Tahe Oilfield through horizontal wells with acid fracturing typically perform poorly after normal acid fracturing,and with difficulty after the application of staged acid fracturing,even with proper tools selection and fracture orientation control.Under such circumstances,numerical simulations were performed to determine the technical feasibility and economic performance of of horizontal wells with flexible fishbone pipes in completion in fractured vuggy carbonate reservoirs.Simulation results showed that production from individual well may increase with the quantity of flexible fishbone pipes when they failed to establish communication among effective fractures and vugs.In addition,production enhancement from each individual set of pipes would increase primarily followed by production decline.For wells with poor communication among fractures,6-10 sets of flexible fishbone pipes can be placed during well completion; For wells with communication among fractures or vugs,oil production would increase and the increase was determined by fractures or vug volume.In general,satisfactory economic performances might be reached as long as fractures or vugs establish communication with flexible fishbone pipes.Research results showed that flexible fishbone pipes completion techniques could be deployed for horizontal wells of fractured vuggy carbonate reservoirs in Tahe Oilfield.It may provide necessary guidance for pilot tests in the application of flexible fishbone pipes in completion operations.