纳米基隔离液NMS-Ⅰ的实验研究

EXPERIMENTAL INVESTIGATION OF NANOMETER BASED SPACER NMS-Ⅰ

以纳米材料LC-212为基料,配合化学凝胶堵剂、羧甲基纤维素和重晶石等材料,考虑塔里木油田的现场实际,实验研制了一种新型隔离液体系NMS-Ⅰ。实验结果表明,该隔离液体系密度可调范围大,流变参数符合梯度匹配原则,静态稳定性好,对水基钻井液及低密水泥浆均无絮凝增稠作用,与水泥浆配伍性较好;利用自制的堵漏模拟装置和剪切式实验装置评价其堵漏性能及对第二界面胶结强度的影响,结果表明其堵漏和冲洗功能较强,能有效提高第二界面胶结强度。此外,在实验基础上分析了隔离液的作用机理。研究结果为解决当前固井工程中的一些实际问题提供了一个新的途径。

Referring to the nanometer material LC-212 as the base stock with the adaptation of the chemical gel plugging agent, carboxymethyl cellulose and barite, and considering the field practice in Tarim oilfield, a new spacer system NMS-Ⅰwas experimentally developed. Results obtained from laboratory tests indicate the system has a wide range of density adjustable, no flocculating or thickening effect on the water base drilling fluid and low-density cement system, and satisfying performance in static stability and compatibility with cement slurry. The rheological parameters of the spacer conform to gradient matching principle. Meanwhile, the seepage control capacity of the spacer and its influence on the second interfacial cementing strength were investigated by self-made lost circulation simulator and shearing test apparatus, results demonstrate the spacer has better sealing and plugging function and higher washout efficiency, and can dramatically improve the second interfacial cementing strength. Moreover, on the basis of the tests, the active mechanisms of the spacer fluid were analyzed in the paper. The investigation results offer a novel approach for some practical problems in current cementing engineering.