矿渣对固井用硫铝酸盐水泥石性能影响研究

Properties of Sulphoaluminate cement with Slag for Cementing

目前,固井基本上是选用G级油井水泥,但随着油气田开采难度和井下情况的复杂化程度增加,固井难度不断加大,常规的油井水泥已不能完全满足工程需要,而具有特殊优异性能的特种水泥在固井工程中的应用研究将成为重点,并具有广阔的应用前景。因而为了探索硫铝酸盐水泥用作固井水泥石的可能性,本文选用矿渣A和矿渣C做为硫铝酸盐水泥的外掺料,针对硫铝酸盐水泥石后期强度倒缩的问题,对硫铝酸盐水泥进行改性。主要研究了矿渣的加量对硫铝酸盐水泥力学性能的影响。宏观上通过考察不同外掺料加量对硫铝酸盐水泥石抗压强度的影响,并通过X射线衍射,对矿渣改性硫铝酸盐水泥组分进行分析;采用岩心孔隙联测仪分析水泥浆水化后孔结构。微观上用扫描电镜对改性前后水泥石的微观形貌对比分析,从而得出宏观上抗压强度提高的原因。

At present,basically the G-level oil well cement is selected in cementing. However,with the difficulties and complexities increasing during the production,cementing process is also getting harder and harder,thus the conventional oil well cement can＇t meet the requirements in the project. In the other word,special cement with high property is the key point of cementing application and with a good prospect. In this paper,we investigate the feasibility of sulphoaluminate cement in replacing the G-level oil well cement. The A-type slag and C-type slag are selected as the addictive to better long term strength decreasing of the sulphoaluminate cement. The purpose of this study is evaluate the influence of mechanical properties in sulphoaluminate cement with different quantity of addictive. At macro level,we measure the compressive strength of the set cement added addictive. XRD was used to analyze the component in samples. We also test samples ＇ pore structure with the Core Porosity Tool. At the micro level,SEM is required to compare the micro-structure of samples which is bettered or not. To summarize,all the characterizations verify the compressive strength improved.