超细油井水泥性能研究及制备工艺探讨

Study on the performance and preparation technology of ultrafine oil well cement

为探讨超细油井水泥性能和制备工艺,本文通过采用立式多转子气流分级机对油井水泥进行分级和相应工序处理获得7种不同颗粒粒径的油井水泥。利用激光粒度仪、X射线衍射仪、扫描电镜等分别对不同颗粒粒径油井水泥进行颗粒级配、矿物组成、水泥颗粒形貌及水泥石水化产物进行测试,同时测试稠化时间、稠度、流动度、强度等对其性能进行评价。研究结果表明,油井水泥在分级生产过程中出现分相现象;分级粗油井水泥在合适比例混合下可获得合格产品;不同颗粒粒径的油井水泥微观结构和物理性能差别大,随水泥比表面积增大,水泥颗粒间吸附力增强,浆体稠化时间缩短,初稠和水灰比增大,析水率降低,稳定性增加;在合适温度范围内,随温度升高,浆体强度增加,但颗粒过细,强度反而会下降。

In order to discuss the performance and preparation technology of ultrafine oil well cement, seven kinds of oil well cement with different particle size were obtained by using vertical multi-rotor air-flow classifier to grade and process the oil well cement. The particle size distribution, mineral composition, cement particle morphology and cement hydration products of oil well cement with different particle sizes were tested by laser particle size analyzer, X-ray diffractometer, scanning electron microscope, etc. At the same time,the thickening time, consistency, fluidity and strength were tested to evaluate its performance. The research results show that the oil well cement appear phase separation in the process of classification production;classified crude oil well cement can obtain qualified products in the appropriate proportion. The microstructure and physical properties of oil well cements with different particle sizes vary greatly, with the increase of specific surface area of the cement, the adsorption between cement particles increases, the thickening time of slurry shortens, the initial thickening and water-cement ratio increase, the water separation rate decreases and the stability increases. Within a suitable temperature range, with the increase of temperature, the strength of the slurry increases, but if the particles are too fine, the strength will decrease instead.