Exploration on geology-engineering integration of hard-to-recover reserves in Shengli Oilfield

Abstract

Effective development of hard-to-recover oil reserves is an important measure to enhance oil development in China. The hard-to-recover reserves of low permeability and heavy oil in the Shengli Oilfield are nearly 6×108t, accounting for more than 10% of the nation. Effective development faces many challenges such as complex oil-water system, lack of supporting technologies and low productivity. Sinopec took Shengli Oilfield as a pilot project. After more than 2 years of cooperative development practice, it has explored a number of effective methods such as "innovation of cooperative mechanism", "searching for sweet spot in low-grade reserves", "geology-engineering integration", "fine reservoir stimulation and increasing productivity". It has preliminarily achieved the goal of "managing, recovering and producing" the hard-to-recover oil reserves. The cumulative produced oil reserves are 4860×104t, established productivity is over 50×104t, the drilling cycle is shortened by more than 60%, single well production is increased by about 40%, and the break-even oil price is dropped from 75 $/bbl to within 50 $/bbl. The practice of producing hard-to-recover oil reserves in Shengli Oilfield has initially formed a unique contracted productivity establishment plan and created an efficient model of geology-engineering integration of the whole industry chain, which has opened up a new direction for the sustainable development of mature oil areas with high degree of exploration.