VES-CO_2清洁泡沫压裂液携砂性能实验研究

Study on Proppant Carrying Capacities of CO_2 Viscoelastic-Emulsified Surfactant Foam Fracturing Fluid

在大型高压泡沫压裂液实验回路上,对VES-CO_2清洁泡沫压裂液的携砂性能进行了实验研究。分析了携砂泡沫压裂液流动时临界沉降速度的产生原因,并根据实验结果分析了温度、泡沫质量及支撑剂浓度对临界沉降流速的影响。临界沉降流速随温度的升高而增大,随泡沫质量和支撑剂体积浓度的增大而减小,研究发现当支撑剂浓度大于0.25时,开始出现颗粒团聚现象,并分析了颗粒团聚现象发生的原因。最后根据实验结果,拟合出了用于计算临界沉降流速的实验关联式。

Proppant carrying capacities of VES-CO2 foam fracturing fluid were researched on the large-scale high pressure test loop. The setting and transport characters of proppant in pipeline were investigated in this paper. The cause of critical proppant settling velocity was analyzed. Effect of temperature, foam quality and proppant concentration on critical proppant settling velocity was analyzed in this paper. The results show that critical proppant settling velocity increases with the rise of temperature, while decreases with the rise of foam quality and proppant concentration. For the proppant concentration exceeds 0.25, particles start to agglomerate. Through analyzing the experimental data, experimental correlation used to calculate critical proppant settling velocity is obtained, and the maximum relative error between the calculated and the experimental results is within 15%.