复合冻胶堵调剂体系研究

STUDY ON COMPOSITE JELLY SYSTEM USED FOR LOSS CIRCULATION CONTROL AND PROFILE CONTROL

本文研究了三种复合冻胶堵调剂体系：（1）HPAM─苯酚─醛体系；（2）HPAM─脲─醛体系；（3）HPAM─糠醇─醛体系。介绍三种体系的典型配方，具体考察了体系对地层环境如高矿化度和原油的表面活性的适应性。实验结果表明：体系成胶前具有良好的可泵性，所成冻胶在75℃时30天不破胶、不析水，体现出较好的冻胶稳定性，成胶后具有很高的强度（成胶剪切强度≥125Pa·s），对高渗透率岩心的堵塞程度也较高。研究了HPAM的分子量、水解度、浓度对所形成冻胶与地层岩石的粘附状态的影响。施工时在前置液中加入适量、合适的促凝剂，以避免配方中反应成分被地层流体稀释而不成胶，以提高成功率。

This paper presents the study on 3 composite jelly systems used for loss circulation control and profile control. The 3 systems are: ①HPAM-phenol-aldehyde system, ② HPAM-urea-aldehyde system,and ③HPAM-furfuryl alcohol-aldehyde system. Their typical formulations are presented. Meanwhile, the article gives out results of the survey of adaptability of these systems to formation environment such as high salinity and surface activity of crude oil, they show that composite jelly system has good pumpability before the system become colloid and the jelly will not breakdown and no water precipitation when 30d at 75℃, so it has good stability. After composite jelly system become colloid, it has very high strength (shear strength≥125Pa·s) and has higher plugging degree to high permeability core. The paper studies the effects of molecular weight, degree of hydrolysis and concentration of HPAM on adhesion of jelly and formation rock. When operation, suitable accelerant is added in preflush to increase success ratio.