摘要
目的原油运输中管道结蜡问题严重影响正常的生产运输,通过表面刻蚀的方法,获得具有超亲水性的粉末冶金黄铜表面,从而达到良好的防结蜡性能。方法结合不同刻蚀时间下的表面微观结构、粗糙特性和润湿特性,对防结蜡性能进行系统研究。采用Fe Cl3溶液,刻蚀粉末冶金黄铜试样不同时间,通过X射线衍射仪和扫描电子显微镜对刻蚀表面的成分和形貌进行分析,利用接触角测量仪测量样品表面润湿性,最后对刻蚀后的黄铜进行防结蜡测试。结果表面刻蚀过程实为"脱锌",在试样表面形成了微纳米级颗粒粗糙结构。随着刻蚀时间的延长,最大轮廓高度Rz相应增大。与未刻蚀试样相比,刻蚀后的试样表面水接触角大幅降低,防结蜡性能显著提升。当刻蚀时间为120 min时,水接触角远小于30°,粉末冶金黄铜表面达到超亲水状态,防结蜡测试后,约80%表面为干净的原始表面,几乎没有石蜡吸附。结论刻蚀表面的亲水成分和棱锥状铜单质颗粒组成的微细粗糙结构,使得其在水相中形成稳定的"水膜",这层水膜可以有效阻止油相中石蜡的析出与沉积,达到良好的防结蜡效果。
Pipeline waxing in crude oil transportation seriously affects normal production and transportation. The work aims to obtain a super-hydrophilic powder metallurgy brass surface by surface etching, so as to achieve good waxing resistance. A systematic study was done on the waxing resistance after anti-wax test by combining surface microstructure, roughness and wettability at different etching time. Ferric chloride solution was used to etch the powder metallurgy brass specimen at different etching time. Composition and morphology of the etched surface were analyzed with X-ray diffraetometer and scanning electron microscope. Surface wettability of the specimen was measured with a contact angle meter. Surface etching was indeed a process of＂dezincification＂. Micro-nano particle coarse structure was formed on the surface of specimen. As the etching time prolonged, the maxinmm contour height Rz increased accordingly. Compared with untreated samples, water contact angle of the surface of specimen was greatly reduced after being etched and the waxing resistance was improved remarkably. When the etching time was 120 min, the water contact angle was far less than 30~, and powder metallurgy brass surface achieved super-hydrophilic state. About 80% of the surface was clean original surface after anti-waxing test, almost no paraffin was absorbed. Stable ＂water film＂ is formed in aqueous phase due to the fine rough structure consisting of hydrophilic composition and pyramid shaped copper particles on the etched surface. This film can effectively prevent precipitation and deposition of paraffin in oil phase, and further achieve good waxing resistance.
出处
《表面技术》
EI
CAS
CSCD
北大核心
2017年第9期153-159,共7页
Surface Technology
基金
国家自然科学基金青年基金项目(51304214)~~
关键词
粉末冶金
黄铜
表面刻蚀
微观结构
超亲水性
防结蜡
powder metallurgy brass, surface etching
microstructure
super-hydrophilic property
anti-waxing
