Abstract
In late stage of high water cut development period, difficulty in plugging high aquifers increases because the initial pore structure near well bore area has been damaged. Therefore, polymer single fluid plugging technique was developed. Single fluid plugging agent is polymerization initiated by free radical. Reaction time, which is 4-6 hours under normal hole temperature from 40°C to 60°C, is controlled by the half life and the inducement period of initiator. Whereas, in actual application, some wells, such as high temperature deep wells or channeling plugging wells, require longer or shorter gel forming period. Therefore, reaction time control analysis of plugging agent was carried out in order to increase safety and maneuverability of field operation and to expand application field. This paper describes the application of single-fluid water plugging technique in late stage of high water cut development period. Based on the actual condition in oilfield development, the recipe and operation process have to adjust correspondingly to make this technique more serialized and popular. The analysis result on field operation and typical well showed that this water plugging technique could increase oil production and decrease water cut, and satisfied the complicated geological condition of late stage in high water cut development period.
