含油污泥对泥-聚回注体系性能的影响

Effect of Oily Sludge on the Properties of Oily Sludge-Polymer Reinjection System

绥中36．1油田产出含油污泥平均含水率77．21％、含油量9．12％、固含量13．67％，粒径峰值约250gm，d．0=30．33gm、d，0=176．94gm、d530．51岫。利用柔性碾磨装置（磨盘间距50pan）降低含油污泥颗粒粒径至注入需求（d90〈50gm），与疏水缔合聚合物AP．P4溶液（1750mg／L）形成有效的回注体系，在聚合物驱的同时实现含油污泥的无害化处理与资源化利用。研究了含油污泥对泥．聚回注体系性能的影响。结果表明，随着含油污泥加量的增大（〈1500mg／L），体系黏度大幅增加，在合油污泥加量30-250mg／L范围内的黏度增幅高于90％，可稳定120h；含油污泥过量（3000mg／L）时，体系黏度降低，降幅达37．28％，并随静置时间延长，黏度降低，稳定性较差。加入少量含油污泥（〈250mg／L）能提高体系的抗剪切能力，剪切应力比不加时要高或与之相近；含油污泥过量（3000mg／L）时，体系的剪切黏度明显低于加污泥前，剪切应力随剪切速率增大而增大，但低于不加含油污泥时的值，且剪切速率越高，差异越明显。加入少量合油污泥（〈750mg／L）可增强体系的凝胶强度，G’／G”远大于不加含油污泥时的值；过量的含油污泥（3000mg／L）会强化体系的絮凝沉降现象，导致其G’／G”值在高频区域陡升，甚至高于其他浓度体系的值。图12表2参17。

The oily sludge originated from Suizhong36-1 oilfleld, was composed mostly of 77.21% formation water, 9.12% crude oil and 13.67% other solid matter with peak size about 250 pan, d90=30.33 Ima, d50=176.94 lain, d90=530.51 larn. The size of solid particles was reduced to meet the requirements of reinjection （d90〈50 min） by flexible grinding device. An effective reinjection system was formed by oily sludge and hydrophobic associating polymer AP-P4 solution （ 1750 mg/L）, which eventually achieved the harmless disposal and resource utilization of oily sludge in the polymer flooding process. In this paper, the influence of oily sludge on the properties of oily sludge reinjection system was studied. Experiment results showed that the apparent viscosity of reinjeetion system increased with increasing dosage of grinded oily sludge （ 〈 1500 mg/L）, and the viscosity increase was more than 90% in the range of 30--250 mg/L with a stationary phase over 120 h. With an overdose grinded oily sludge （3000 mg/L）, the apparent viscosity of reinjection system reduced sharply by 37.28%, and appeared lower viscosity and poor stability with the extension of standing time. Adding a small amount of oily sludge （ 〈250 mg/L） could improve the shear resistance of reinjection system, and its shear stress was higher than or near to the value of AP-P4 solution without oily sludge. While excessive oily sludge （3000 mg/L） significantly decreased the shear viscosity of reinjection system, and its shear stress increased with increasing shear rate, but was lower than that of AP-P4 solution without oily sludge. Moreover, when the shear rate was higher, the difference was more obvious. With a little dose of grinded oily sludge （ 〈750 mg/L）, the gel strength of reinjection system were enhanced, and G/ G was much larger than that of AP-P4 solution without oily sludge. While excessive oily sludge （3000 mg/L） drastically enhanced flocculation sedimentation and led to stratification in reinjection system, which ultimately resulted in a rapid increase of G/Gat high frequency, and even was higher than that ofreinjection systems with other concentration.