油田堵剂最佳注入时间的研究

A study on the optimum injection time of water shutoff agents.

堵水作为控制油井含水、提高水驱效果的一项重要措施 ,在注水开发油田发挥了十分重要的作用 ,而堵剂封堵作用的好坏很大程度上取决于堵剂的选择性进入能力。以岩心试验为基础 ,根据地层高、低渗透层压降速率的差异 ,研究了关井时间对堵剂在高、低渗透层分配量的影响 ,从理论和实验上证实 ,油田堵剂存在发挥封堵作用的最佳注入时间。根据压降曲线特征 ,通过曲线拟合得出数学公式 ,据此用求极值的方法确定油田堵剂的最佳注入时间。研究结果表明 ,要充分发挥堵剂的封堵作用 ,选择适宜的注入时间十分重要。图 2参

Water plugging treatment in oil fields is a key measurement to control water in production well and improve waterflooding performance by reducing fluid channeling through high permeability thief zones.It plays an important role in waterflooding oil fields. The effect of such treatment often depends on placing the water shutoff agents in thief interval. Based on the difference of pressure drop rate in higher and lower permeability zones and the core experiments, the effect of well shut in time on the distribution of water shutoff agents was studied in this paper. It was proved that the water shutoff agents have an optimum injection time to play their plugging effect theoretically and experimentally. Based on the characteristics of pressure drop curve, the mathematical equation was obtained from curve fitting. The optimum injection time of water shutoff agents may be determined by using the method of calculating extreme value mathematically. It was turned out that selecting an appropriate time to inject water shutoff agents is very important to fully play their plugging effect.