叔胺型清洁压裂液体系的制备与性能评价

Preparation and performance evaluation of tertiary amine clean fracturing fluid system

针对阳离子型表面活性剂压裂液在地层中产生吸附,进而对储层造成二次伤害等问题,室内以油二胺为原料,利用Eschweiler-Clarke反应,合成了一种长链叔胺(以下称OADA)。以OADA作增稠主剂,醋酸为助剂,研究了氯化钾加量、主剂与醋酸的摩尔比对体系黏度的影响。考察了OADA清洁压裂液体系的耐温抗剪切性、黏弹性、悬砂性等性能指标。室温下通过对体系进行频率、应力扫描得出该体系以弹性为主;体系在100℃、170 s^(-1)下连续剪切1 h,仍有大于25 mPa·s的黏度。破胶液具有较低的黏度和表界面张力,对岩芯的损害率仅为5.82%,具有低伤害特性,与地层水配伍性良好。

Aiming at the problem that cationic surfactant fracturing fluid adsorbs in the formation and causes secondary damage to the reservoir,a long-chain tertiary amine(hereinafter referred to as OADA)was synthesized in the laboratory using oil diamine as raw material and Eschweiler-Clarke reaction.OADA was used as thickening agent and acetic acid as assistant.The effects of the amount of potassium chloride and the molar ratio of the main agent to acetic acid on the viscosity of the system were studied.The performance indexes of OADA clean fracturing fluid system,such as temperature resistance,shear resistance,viscoelasticity and suspended sand,were investigated.By scanning the frequency and stress of the system at room temperature,it is found that the system is mainly elastic.The system still has a viscosity of more than 25 mPa·s when it is continuously sheared at 100℃and 170 s^(-1)for 1 h.The gel breaker has low viscosity and surface interfacial tension,and the damage rate to the core is only 5.82%,it has low damage characteristics and good compatibility with formation water.