Special Oil & Gas Reservoirs ›› 2024, Vol. 31 ›› Issue (6): 145-150.DOI: 10.3969/j.issn.1006-6535.2024.06.018

• Drilling & Production Engineering • Previous Articles     Next Articles

Study on the Influencing Factors of Diversion Agent Performance Suitable for New Volume Fracturing Technology

Liu Shun1,2, Liu Jianbin1,2, Chen Xin1,2, Zhou Zhixiang1,3, Huang Kai1,4, Du Hengyi1,5, Zhang Yalong1,5, Wang Zongzhen1,2   

  1. 1. College of Petroleum Engineering,Xi'an Shiyou University,Xi'an,shaanxi 710065,China;
    2. Shaanxi Key Laboratory of Advanced Stimulation Technology for Oil & Gas Reservoirs,Xi'an,shaanxi 710065,China;
    3. China Petroleum and Chemical Corporation Jiangsu Oil Field Branch,Yangzhou,Jiangsu 225009,China;
    4. China Petroleum and Chemical Corporation Zhongyuan Oilfield Branch,Puyang,Henan 457001,China;
    5. PetroChina Changqing Oilfield Company,Xi'an,shaanxi 710018,China
  • Received:2023-07-04 Revised:2024-08-26 Online:2024-12-25 Published:2025-01-22

Abstract: The technology of volume fracturing by diversion agent requires that the deblocking time is within a few hours,whereas it usuallysustain several days,which cannot meet the requirements.To address the issue,an aqueous solution polymerization method was employed,utilizing cellulose as the main component,acrylamide as the graft monomer,and N,N-methylene bisacrylamide as the crosslinking agent,to synthesize a diversion agent.The study investigated the effects of temperature,salinity,oxalic acid content,and particle size of the crosslinking agent on its performance under reservoir conditions.The results indicate that the temporary storage agent exhibits good temperature resistance,with a residual rate remaining stable;at a temperature of 60 ℃,the flowable time of theagent is 2.60 hours,the dissolution time is 7.43 hours,and the residual rate is 7.25%.The dissolution rate slightly slows down with increasing salinity,and its dissolution rate in CaCl2 solution is slower than in NaCl solution,which demonstrates good salt tolerance.The diversion agent exhibits good compatibility with fracturing fluids,with slightly extended flowable time and dissolution time in the fracturing fluid.The oxalic acid content has a minimal impact on the residual rate of theagent.As the particle size of the agent decreases,its flowable time and dissolution time exhibit a trend of slow decrease followed by an increase,and the flowable time and dissolution time with combined particle sizes are longer than those with a single particle size.The research results provide a theoretical basis for optimizing the performance of diversion agent and studying their migration patterns.

Key words: volume fracturing, diversion agent, dissolution pattern, deblocking

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