温敏堵漏水泥浆体系研究与应用

Research and application of the temperature sensitive plugging cement slurry system

温敏形状记忆聚合物是形状记忆材料的一种,其结构中存在记忆起始形状的固定相和随温度变化能可逆地固化和软化的可逆相。本文将这种材料性能应用于石油工程的固井领域,利用温敏聚合物温敏形变的特点,在井下温度升高时激发粒子形变形成大形变体,为封堵漏失层提供架桥结构,解决固井水泥浆防漏堵漏效果差、水泥车不能泵送较大尺寸颗粒的难题。研制的温敏堵漏材料初始粒径1 mm,达到温敏点后体积形变膨胀,应用温度60~140℃,加量0~2%BWOC;据此构建的温敏堵漏水泥浆体系,能有效封堵2 mm的缝隙板,承压7 MPa。温敏堵漏水泥浆先后在东北分公司北209井、北8井、北213-1井等的尾管或油层固井中进行了现场应用,尤其在北213-1井的固井堵漏过程中有效解决了固井漏失难题。

Temperature sensitive shape memory polymer is a kind of shape memory material. In its structure,there are fixed phases that remember the initial shape and reversible phases that can be cured and softened reversibly with temperature. In this paper,these properties of materials are applied to the cementing field of petroleum engineering.The temperature sensitive deformation characteristics of temperature sensitive polymer allows the particle deformation to be excited at high downhole temperature to form a large deformation,which provides a bridge structure for sealing and plugging the lost circulation layer;thus,solving the problems of poor leakage prevention and plugging effect of cementing slurry,and inability of the cement truck to pump large particles. The initial particle size of the temperature sensitive plugging material is 1mm. After reaching the temperature sensitive point,it deforms and expands in volume.The application temperature is 60 to 140℃,and the dosage is 0 to 2% BWOC;The temperature sensitive plugging cement slurry system prepared on these conditions can effectively seal the 2mm slotted plate at 7MPa. The temperature sensitive plugging cement slurry has been applied in North-209 well,North-8 well and North-213-1 well for cementing of the liner or oil bearing layers by the Northeast oil and gas branch company successively,especially in North 213-1 well where it effectively solved the problem of cementing leakage.