页岩油储层改造用压裂液体系的研究及应用

Study and Application of Fracturing Fluid System for Reconstruction of Shale Oil Reservoirs

根据江汉油田页岩油藏具有低～中孔隙度、低～特低渗透率、地质构造复杂、敏感性强等非常规油藏的特征，室内研制了羧甲基羟丙基胍胶低伤害压裂液体系，评价了羧甲基羟丙基胍胶压裂液的溶胀性能、耐温抗剪切性能、破胶性能和对储层的伤害性能，以及无机盐离子对基液黏度的影响。实验结果表明，该压裂液的使用浓度为胍胶压裂液使用浓度的1／2时即可满足压裂施工的携砂要求，并且破胶后残渣含量低，降低了对储层的伤害，在潜页X井大规模压裂施工中应用成功。

According to the characteristics of shale oil reservoirs in Jianghan Oilfield, namely low-middle porosity, low-ultra low permeability, complex geological structure and strong sensitivity of unconventional reservoir, a kind of fracturing liquid system of carboxymethyl hydroxypropyl guar gum （CMHPG） with low damage has been developed, and evaluation on the swelling property, temperature resistance, shear resistance, gel breaking performance, the damage to reservoir and the influence of inorganic cation on viscosity of base fluid of CMHPG has also been conducted. The experimental results show that when the concentration of CMHPG is the half of HPG＇s, the requirement for carrying proppant during fracturing can be met. In addition, the content of residue is low after gelout, and the damage to the reservoir is also reduced. The application of CMHPG for large scale fracturing in X well of Qianye area is successful.