Chaheji Oilfield Fracturing Technology Research And Applications

During the metaphase and anaphase of Chaheji oilfield development, the primary focus was on exploration of new section and development of residual oil. Reservoir stimulation was used to keep the yield stable, which has became the standard technique in the development. In the early 80' s, hydraulic fracturing technique was applied for the development. However, since the complexity of geology and limitation of cognition and technology, the efficiency was poor.In this paper, geology and stimulation were analyzed, the reasons that cause the poor efficiency of stimulation were summarized, and the principles of hydraulic fracturing after time were made. Combining with oilfield reality, the principles of well choice in fracturing were determined, the position of oil well in sand body, the sand body through-going and the fracture azimuth were regarded as important well choice basis, thereby, the blindness of well choice was avoided and the success ratio of measure was ensured. The design of hydraulic fracturing scheme had more directionality, which adopted the way of packer separate-layer fracturing in small well section, benefiting to thoroughly reconstruct main producing pay. The high-property hydroxypropylguar gum fracture fluid, organic boron crass linking agent and ceramist sand propant were applied in the choice of fracturing material, enhancing the intake volume and sand-fluid ratio, increasing the procedure of pump-in taking segmentation were used in construction technology. In the 2001, 5 wells were performed in the Chaheji oilfield, ratio of success and efficiency were 100 percent respectively. The enhanced production level was 8 ton/day per well after stimulation, and the enhanced accumulation yield has added up to 10492 ton. The remarkable benefit of economy and society was achieved.