Evaluation And Application Of Acid Pressure Temporary Plugging Diverting Agent

As an important measure to increase the production of carbonate reservoirs,the key to fracturing acidification technology is whether it can evenly distribute acid throughout the reservoir,so as to relieve the pollution in the near-well zone and the new circulation between the reservoir and the wellbore,thereby increasing the production of oil and gas wells.At present,conventional acidizing and fracturing cannot meet the requirements of the current re-engineering.For such problems,repeated acidizing and fracturing technology has emerged,and the fiber is temporarily blocked for easy operation,clean and complete degradation,no pollution to the reservoir,etc.Features have gained more and more research and application since the 21st century.This paper mainly studies the screening and performance test of fiber temporary plugging agent,the temporary blocking law of fiber temporary plugging agent,the exploration and development of non-fiber temporary plugging agent and the field of fiber temporary plugging agent.The results are as follows:(1)Screening of various fiber materials,preferably two kinds of fibers with a temperature resistance of 140? and a temperature resistance of 160?,and the cost reduction exceeds 30%,enriching the types of optional fibers.(2)The concept of critical carrying density is proposed,and the different carrying liquids correspond to different critical carrying fiber concentrations,and the corresponding values are measured.(3)Upgrading and reforming a slot width adjustable acid pressure temporary plugging strength test simulation device,slit width range:(0.5-8mm),temperature range:(room temperature-170?),pressure range:(0-35MPa).(4)Pure fiber can be blocked for cracks with narrow slit width(<2mm),and the temporary plugging strength is greater than 18MPa.For cracks of 4mm size,1.0%of 6mm fiber+0.5%2mm particles can be used,and the temporary plugging strength can reach 22.89MPa.For large slit width,6mm crack is preferred for temporary plugging formula:1.2%of 6mm fiber+0.5%6mm of pellet+1.0%1-2mm of pellet is the experimental optimum formula.(5)Exploring the new temporary plugging agent,developing the temporary blocking acidification water expansion;the degradation rate of 2h in 20%HCl at 100? is less than 30%,and can be completely degraded within 24h.(6)During the on-site construction process,the pump pressure increased by 9 MPa when the pump was temporarily plugged,and the temporary plugging effect was obvious.The daily oil production after construction was 104.8 t/d,and the cumulative oil increase was 1,641 tons.The effect of increasing production was remarkable.(7)Analyzing the shortcomings of acidizing and fracturing temporary plugging in the field construction process materials,on-site process and filling method,and proposing corresponding solutions.