罕见矿物——六方球方解石的发现及特征

DISCOVERY AND CHARACTERISTICS OF THE RARE MINERAL—VATERITE IN OIL-PUMPING OIL WELL

大庆油田部分三元复合驱抽油井结垢现象比较严重。井中结垢损害抽油设备 ,增加了生产成本。通过运用XRD ,IR ,SEM和化学分析手段对抽油井垢的研究发现 ,垢的主要化学成分为CaO和SiO2 ,其含量分别为67%和 2 8% ,油井垢中的主要矿物成分是罕见矿物———六方球方解石。六方球方解石呈微晶状 (1～1 0 μm) ,并常常以微晶聚集的球粒状出现 ,同时伴生有无定形SiO2 。呈游离态的SiO2 和有机质对于六方球方解石的形成起到了重要作用。

The scale that precipitated in ASP driven pump oil well is a very seri ous problem in oil production in Daqing oil field of China. The growth of scale often damages the drilling machine and increases the production cost. The study on XRD, IR, SEM and chemical analysis of scale show that the chemical compositio n of scale are mainly CaO and SiO 2, which account nearly for 67% and 28% separ ately. A rare mineral, vaterite, was found in the scale, which is a tiny crystal (1-10 μm), often in the form of crystallite aggregates and usually associated with amorphous SiO 2. It is suggested that the dissociated SiO 2 and organic matter in pump oil well play an important role in the formation of vaterite.