应用环境扫描电子显微镜定位观察酸蚀过程

THE APPLICATION OF ENVIRONMENT SCANNING ELECTRON MICROSCOPE IN OBSERVATION OF CORE BEFORE AND AFTER EXPOSED TO ACID

砂岩基质酸化酸岩反应和二次伤害机理研究是优选酸液体系与优化酸化设计的基础 ,环境扫描电子显微镜 ( ESEM)是进行此项研究的重要工具 ,其特点是 :含油水的新鲜样品无需清洗、干燥、镀膜等样品制备过程 ,可直接放在镜下观察 ,且样品可保持在 1 0 0 %湿度条件下工作。利用环境扫描电子显微镜仪器特性 ,结合岩心酸浸泡试验 ,定位观察研究了用不同酸液、在不同酸蚀时间下的砂岩岩心中长石和粘土等矿物的变化及岩心孔隙喉道和酸溶蚀孔洞的形成状况。

Sandstone matrix acidizing is a very effective stimulation method to remove the damage nearby the wellbore in sandstone reservoir The study on acid/rock reaction and mechanism of secondary damages to formation is the basis of optimizing acid system and acidizing design. The Environmental Scanning Electron Microscope (ESEM) plays an importance role in the work. By saturating the specimen chamber with water vapor during examination, the ESEM allows wet or oily specimens to be imaged and analyed in their 'native' state without drying, freeing, cleaning or coating with a conductive layer. Based on the features of ESEM and along with core acidizing, the change of mineral, porosity, and wormhole at the same position of the core can be imaged. The high magnification images provide detailed information about the change of core.\;