Study On A Degradable Fiber Temporary Plugging Re-fracturing Technology And Its Applications

Optimizing suitable temporary plugging agent is a key factor of temporary plugging fracturing,the degradable fiber dosen't have the function of temporary plugging,but also have the effect of suspended sand,backflow prevention and so on.So choose one degradable fiber,and use soakage as surface modification treatment to improve the fiber dispersion and its affinity with proppant,we also evaluate its temporary plugging ability,suspended sand performance and fracture diverting capacity and proppant backflow prevention performance.Meanwhile the ground stress model of temporary plugging has been built,and we use this model to calculate a test well of Sulige,we acquire a good effect at last.By the experiment of supporting the collapse of the sand body to study the fiber length and diameter,in the end,we choose 10?m diameter and 8mm length fiber as temporary plugging agent.And we evaluate its dispersity,compatible performance and suspended sand performance.We also study the performance of temporary plugging.The results showed that fiber-based fracturing fluids can't only significantly improve the effect of suspended sand performance,but also have a good performance in dispersity,compatible performance,if we add this fiber into the fracturing fluid,the fiber can form a fiber mesh which can extend the time of suspending sand and prevent the sand back-flow.9‰ fiber concentration can make the highest breakthrough pressure in 10 cm cores of 0.3MPa.In the experiment of simulation of temporary plugging in fracture flow meter,12‰ fiber form the difference pressure between measurement chamber is 5.748 MPa.At last,we choose 12‰ as fiber concerntration.In the temporary plugging of test well,we change the fiber concerntration twice,and the curve shows that deflection fracturing has happened,it shows that temporal plugging re-fracturing can be achieved between the fiber concerntration of 13‰ to 18‰.