八面河油田稠油CO_2复合吞吐效果评价

CO2具有提高稠油弹性能、降低原油粘度和油水界面张力的作用,实施复合吞吐能有效改善热采效果。对中渗薄互层油藏,注入CO2后,焖井时间应大于3天;复合吞吐后的放喷,应控制放喷压力,防止近井地层和井底井筒降温对储层造成冷伤害。吞吐后的生产过程中,要保持和延长吞吐作用效果,必须控制生产液量和套压。

Effect Evaluation of CO2 Composite Huff-Puff of Thick Oil in Bamianhe Oilfield

CO2 plays a role in increasing thick oil resilience and decreasing viscosity of crude oil and tension of oil--water interface, so conducting composite huff--puff can improve thermal recovery effectively. After CO2 is injected into mid--permeability thin interbed reservoir, soak time should be more than three days. Blowout pressure should be controlled after composite huff--puff to prevent the reservoir from cold damage due to cooling of near borehole formation and bottom hole. In the production process after huff--puff, withdrawal rate and casing pressure should be controlled to maintain and extend huff--puff effect.