剪切作用对聚丙烯酰胺驱油剂黏损率的影响规律

Influence Law of Shearing Action on Adhesion Loss Rate of Polyacrylamide Oil Displacement Agent

孔繁荣 李传宪 商永滨 杨 飞 许 甜 时光宇

KONG Fan-Rong LI Chuan-Xian SHANG Yong-Bin YANG Fei XU Tian SHI Guang-Yu

用控制应力流变仪，考察了30℃、不同剪切速率下，聚丙烯酰胺（HPAM）溶液表观黏度随剪切时间的变化，以反映管流剪切条件对HPAM溶液黏度的影响规律。根据现场条件，通过计算得到不同浓度HPAM驱油剂在输送管线流动对应的剪切速率和剪切时间。结果表明，在剪切速率为3.11~7.76 s-1、剪切时间为55~22 min时，高浓度（5000 mg/L）HPAM驱油剂黏度随剪切时间的延长略有上升，单位时间黏损率为-0.43%/h~-0.91%/h。在输送过程中的管流剪切对高浓度HPAM驱油剂黏度损失没有影响。在剪切速率为36.84~92.10 s-1、剪切时间为2.26~0.90 h时，低浓度（1000、2000 mg/L）HPAM驱油剂黏度随剪切时间的延长逐渐降低，单位时间黏损率分别为0.08%/h~0.86%/h、0.07%/h~0.30%/h。在低浓度范围内，随着HPAM驱油剂浓度的降低，剪切历史对HPAM驱油剂黏度及黏损率的影响增大。浓度的提高有利于降低驱油剂的黏损率。

The apparent viscosity change of polyacrylamide (HPAM) solution with shearing time was studied by control stress rheometer at 30℃ and different shear rate, which reflected the influence law of shear flow conditions on the viscosity of HPAM solution. According to the site conditions, shear rate and shear time of different concentration of HPAM oil displacement agent in pipeline flow were obtained by calculating. The results showed that when the shear rate was 3.11—7.76 s-1 and shear time was 55—22 min, the viscosity of high concentration (5000 mg/L) HPAM oil displacement agent increased slightly with the extension of shear time. The adhesion loss rate per unit time was -0.43%/h—-0.91%/h. In the process of conveying, pipe flow shear had no effect on the viscosity loss of high concentration HPAM oil displacement agent. When the shear rate was 36.84—92.10 s-1 and shear time was 2.26—0.90 h, the viscosity of low concentration (1000, 2000 mg/L) HPAM oil displacement agent gradually reduced with the extension of shear time. The adhesion loss rate per unit time was 0.08%/h—0.86%/h and 0.07%/h—0.30%/h, respectively. In the range of low concentration, the influence of shear history on the viscosity and adhesion loss rate of HPAM oil displacement agent increased with decreasing concentration of HPAM flooding agent. Increasing concentration was helpful to reduce the adhesion loss rate of oil displacement agent.