Quartz sand is a very practical basic material in unconventional gas mining.In the service process of quartz sand simulated by formation water,it was found that the breakage ratio decreased.Two kinds of quartz sand were selected to soak in formation water at constant temperature for different time.XRF,XRD,SEM,EDS,XPS and FT-IR were used to characterize the quartz sand before and after soaking to explore its aging resistance mechanism.XRF results show that the content of ClO2 increases after soaking,SiCl4 and anorthite peaks are detected in XRD results,and Cl 2p and Ca 2p peaks also appear in XPS results.These results reveal that Cl-ions in formation water can enter the quartz sand gap and react with SiO2 to form SiCl4,thereby generating silica gel,which coats the sur-face of quartz sand and blocks the contact between quartz sand and water.In addition,the formed anorthite is atta-ched to the surface of quartz sand,which increases the strength of quartz sand,thus improving the crushing resist-ance of quartz sand.
关键词
石英砂/耐老化机理/破碎率
Key words
quartz sand/aging resistance mechanism/breakage ratio
维普
万方数据