压裂液长期滞留对低渗透储层的伤害试验研究

Experimental Study on Damage of Fracturing Fluid to Low Permeability Reservoirs After Long-term Retention

针对当前低渗透油藏中大量使用的压裂液给储层带来的伤害,导致开采量降低的问题,以羟丙基瓜尔胶压裂液作为研究对象,以适应充填装置作为储层模拟,以渗透损失率作为评价指标,探讨不同因素对羟丙基瓜尔胶滞留的影响.结果表明,不同羟丙基瓜尔胶压裂液浓度、pH 值和温度对渗透损失率和压裂液滞留量都有着影响.其中浓度越大,对渗透损失率的影响越大,但随着浓度的持续增加,其影响也逐步变小;pH值越大,对渗透损失率的影响越小;温度与渗透损失率和滞留量呈现为正相关关系.由此通过上述的研究,为石油开采中压裂液的配比提供了参考,对减少压裂液对储层的损害具有可借鉴性.

In view of the reservoir damage caused by fracturing fluids widely used in low permeability reservoirs,resulting in the reduction of production,the hydroxypropyl guar gum fracturing fluid was taken as the research object,the suitable filling device was taken as simulated reservoir,and the permeability loss rate was taken as evaluation index,the different factors affecting hydroxypropyl guar gum retention were investigated.The results showed that different HPG fracturing fluid concentration,pH value and temperature had influence on the permeability loss and fracturing fluid retention.The higher the concentration,the greater the impact on the permeability loss rate;the higher the pH value,the smaller the impact on the permeability loss rate;there was a positive correlation between the temperature with the permeability loss rate and fracturing fluid retention.Therefore,the research can provide reference for the proportion of fracturing fluids in oil exploitation,and can also provide reference for reducing the damage of fracturing fluids to reservoirs.