Youqi dizhi yu caishoulu (Jan 2024)
New comprehensive management method and engineering practice path for mature oilfields with high water cut
Abstract
In response to the development issues faced by chemical flooding in the mature Shengli Oilfield with high water cut in terms of science， technology， management， and engineering， Block Bohai 76 was taken as a typical unit， and the specific countermeasures were analyzed in engineering practice. A new comprehensive management method was constructed for chemical flooding in mature oilfields： “Appropriate， Specialized， Fast， and Integrated.” Among them， “Appropriate” refers to the construction of optimal changing timing models for chemical flooding in different oil reservoirs of mature oilfields during the transformation of scientific development methods for mature oilfields. It was proposed that the favorable changing timing for chemical flooding is at the relatively low water cut stage， and efficient development methods should be used in an appropriate manner. “Specialized” refers to changing the traditional development approach of dissolving polymers before injection in the application of development technology for mature oilfields， developing controllable phase conversion polymers to enable polymer injection followed by dissolution， overcoming the problem of borehole shear degradation， and improving the ability to control oil-water fluidity. The development issues in mature oilfields need to be specifically addressed. “Fast” refers to the transformation in the traditional comprehensive management mode of mature oil fields， which involves a “serial” management mode of problems proposed by fields， schemes designed by research institutes， and oil displacement agents produced by chemical plants. A “parallel” management mode was proposed that fully leveraged the advantages of fields， research institutes， and production plants， and the industrial chemical technology packages and industrialization implementation plans were formed for a single oil reservoir. The development technology of mature oilfields can thus achieve fast transformation. “Integrated” refers to breaking the engineering process model of large-scale construction of chemical flooding stations in mature oilfields during engineering application practice， adopting integrated assembly of injection equipment， achieving the rapid and integrated injection allocation of chemical flooding in mature oilfields， and thus ensuring “integrated” application of engineering processes in mature oilfields. A transition from water flooding to controllable phase conversion polymer flooding was implemented using the above method in Block Bohai 76 of Shengli Oilfield at the early stage of the comprehensive water cut increase. The significant water cut reduction and oil increase effects were observed after one year. The average oil production rate per well increased by 8.6 t/d， and the comprehensive water cut decreased by 3.1%. The feasibility of the comprehensive management model was verified， providing an effective path for the efficient development of chemical flooding in mature oilfields with high water cuts.
Keywords
