Research and Design on the Segregated Production with Horizontal Well in Bottom Water

At present, the oil recovery percent is low in most of the bottom water reservoirs, and the oil production results are always not satisfactory. How to enhance the oil recovery of such reservoirs, this is the pursuit and goal for all reservoir engineers. With the bottom water reservoir in Neogene Guantao formations of Zhuanghai 8 block in Dagang oil field as an example, through analysis of the experiences and developemt lessons in this kind of bottom water reservoirs, we have conducted the research on the pressure drop and flow regularity along the way of irregular wellbore trajectory in horizontal segment in heterogeneous bottom water reservoir, and quantitative analysis about the pressure and flow regularity within horizontal segment in horizontal well, and made clear about bottom water coning regularity. On the basis of the study results, the design of horizontal well has been optimized. In addition, combining with the study about reservoir distribution, the trajectory of the horizontal well, water flooding sweep and producing region of reservoirs, the technique of sand control completion and segmented exploitation in horizontal well is proposed. This technique is very effective in controlling producing pressure drop within long horizontal segment, and the equilibrium oil recovery in horizontal segment has been achieved with this technique. It has been proved through the actual production that the production rate has increased by two times or more with segmented exploitation method compared with not using this method. The water cut has been controlled and oil production has increased by using this technique, which provides a new method to improve oil development results in hori-zontal well for such reservoirs at home and abroad.