低碳烃无水压裂液体系构建及性能评价

非常规油气储层采用水基压裂液压裂施工过程中，易对储层造成二次伤害，并且浪费大量的水资源。因此，室内以正己烷为基液，通过优选合适的交联剂和胶凝剂，研制了一种低碳烃无水压裂液体系，并对其综合性能进行了评价。结果表明：低碳烃无水压裂液体系具有良好的耐温抗剪切性能、黏弹性能和携砂性能，能够满足现场加砂压裂施工的需求。体系的破胶性能良好，加入2. 4%的破胶剂醋酸钠破胶2. 5 h后体系黏度可以降低至10 mPa·s 以下。此外，压裂液体系破胶后对储层岩心的渗透率伤害率小于10%，具有低伤害的特点。低碳烃无水压裂液体系现场应用效果较好，SS-Y2井压裂后日产油量显著提高，达到了压裂增产的目的。研制的低碳烃无水压裂液体系在非常规油气储层压裂施工领域具有较为广阔的应用前景。

Development and Performance Evaluation of Waterless Fracturing Fluid System with Low Carbon Hydrocarbon

The hydraulic fracturing process with water-based fluids in unconventional oil and gas reservoir may easily cause secondary permeability damage to reservoir and waste a great amount of water. Therefore, a waterless fracturing fluid system with low carbon hydrocarbon was developed with n-hexane as base fluid by optimizing the appropriate crosslinking agent and gelling agent,and its comprehensive performance was evaluated. The results show that the low carbon hydrocarbon waterless fracturing fluid system has the characteristics of good temperature resistance,shear resistance, viscoelasticity and sand carrying performance, which can meet the requirements of on-site sand fracturing operation. The gel breaking performance of the system is good, and the viscosity of the system can be reduced to less than 10 mPa·s after adding 2. 4% gel breaker sodium acetate to break the gel for 2. 5 h. In addition, the permeability damage rate of fracturing fluid system to reservoir core after gel breaking is less than 10% ,which is characterized by low permeability damage. The field application effect of low carbon hydrocarbon waterless fracturing fluid system is good,and the daily oil production of SS-Y2 well after fracturing is significantly increased, achieving the purpose of fracturing stimulation. The developed low carbon hydrocarbon waterless fracturing fluid system has a broad application prospect in the field of unconventional oil and gas reservoir fracturing construction.