Research and Application of the Novel Deep Plugging Method in the Oilfield

摘要

In long-term water drive reservoir, small dose and short radius profile control cannot meet the needs, so deep profile control and flooding are needed. During the placement and processing of conventional deep profile control and flooding agent, the zone classification formed by the changes of pressure field and fluid field are not taken into account. In order to better develop these reservoirs, we proposed a novel deep profile control method, that is, the iso-pressure drop gradient progressive deep profile control method. The key features of the method include: 1) the method took into account the reservoir pressure distribution; 2) it proposed a novel standard to divide the orders of zone; 3) the method has been successfully applied in 4 wells in China Oilfield. The method divided the formation into near wellbore zone, well-far zone and deep zone according to the drawdown curve. As each zone of the pressure gradient is different and therefore require different intensity of slug. Then design the agent slugs according to iso-pressure drop gradient rule, and the breakthrough pressure gradient of agent is equal to the formation pressure gradient, and it achieved the fluid diversion of whole course by combining the different intensity of blocking agent. The method was applied successfully in 2 wells in China Oilfield from May to November in 2008. The method can smartly improve the sweep efficiency, and field test shows that it can play a very good efficiency of reducing water and increasing oil production. This method is becoming more of a concern in the oilfield develop.