海上高凝油油藏开发技术对策研究

Technical development measures of offshore high pour-point oilfield

渤海K油田是典型的高凝油油藏,高效开发难度大。为此,对储层原油及储层敏感性进行了评价研究,并开展了相应的注采技术对策研究。注水工艺上,建立了注水井井筒温度场计算模型,优化了注水井的注水温度。采油工艺上,推荐油井采用隔热油管保温生产,通过提高产液温度防止井筒结蜡。研究结果表明,该油田储层水敏和酸敏较为严重;为防止注水引起的地层冷伤害,井口注水温度应不低于60℃;为达到防蜡目的,油井隔热油管下深为600～1 500 m。现场实施效果表明,油田投产后注水温度满足设计要求,注水水质稳定;油井井筒中未出现结蜡问题,生产稳定,充分发挥出了该油田的生产潜能,促进了海上油田的高效开发。

Bohai K Oilfield is a typical high pour-point oilfield,which is difficult to develop efficiently.Based on the characteristics of the oilfield,the sensitivity of crude oil and reservoir was evaluated.Corresponding measures of injection and production technologies were studied to improve the development effect.In the injection aspect,it was established a wellbore temperature field calculation model for water injection wells,and the temperature of injected water was optimized.In the production aspect,vacuum-insulated tubing was recommended for wax control through increasing temperature of production fluid.Research result showed that the formation is serious water and acid sensitivity.To prevent the formation cold damage,the temperature of injected water should not be less than 60℃.The setting length of vacuum-insulated tubing is about 600 m to 1500 m to control wax deposition.Field results indicated that after the oilfield putting into production,the temperature of injected water meets the design requirement.Non-wax problem occurred in wellbore is benefit to guarantee stable production.All of these measures promoted the high-efficient development of this oilfield.