裂缝稳定剂实验评价

针对疏松砂岩储集层压裂后裂缝容易失效的问题,优选适用于该类储集层压裂缝的裂缝稳定剂,通过室内实验对其性能进行评价,优化其用量,并分析其与常用压裂液的适配性.实验优选出一种改性树脂作为裂缝稳定剂,该剂可在支撑剂表面形成一层带有一定强度的黏性膜,轻微降低裂缝导流能力,但能起到稳定支撑剂充填裂缝的作用.实验分析了不同裂缝稳定剂配比下的支撑剂导流能力和防砂效果以及裂缝稳定剂与胍胶压裂液、表面活性剂压裂液(VES 压裂液)的适配性.根据导流能力和微观地层微粒侵入现象对裂缝稳定剂用量进行了优化.推荐选用质量分数为3%~5%的裂缝稳定剂处理支撑剂,并用于胍胶压裂液.模拟现场实验表明,裂缝稳定剂能保持裂缝导流能力;用稳定剂处理过的支撑剂中侵入的地层微粒明显减少.图9表1参14

Experimental evaluation of fracture stabilizers

To avoid the closure of once created fractures in unconsolidated sandstone reservoirs after fracturing, an optimum fracture stabilizer was selected through experimental evaluation, dosage optimization and analysis of its suitability with other commonly used fracturing fluids. A modified resin was selected as the fracture stabilizer, which can form an adhesive film with certain adhesion intensity on the surface of the proppant to fill fractures despite the slightly decreased conductivity. The conductivity, sand control effect, suitability with guanidine gum and viscoelastic surfactant fracturing fluids (VES) of fracture stabilizers with different ratios were evaluated in the experiment. The dosage of the fracture stabilizer was optimized according to conductivity results and sand control effect. After a comprehensive evaluation, the fracture stabilizer whose content ranges from 3% to 5% was used to process the proppant and the guanidine gum fracturing fluid. The simulation experiments show that the flow conductivity of fractures could be maintained by fracture stabilizers and in the proppant processed by stabilizers the number of particles intruding into the formation was significantly reduced.