高含蜡胶凝油的蜡晶显微特性  

Microscopic characteristics of wax crystal in gelling oil with high wax content

作　　者：任翌劼 黄启玉[1] 朱方达 王文达[1] REN Yijie HUANG Qiyu ZHU Fangda WANG Wenda(China University of Petroleum （Beijing）/National Engineering Laboratory for Pipeline Safety/Beijing Key Laboratory of Urban Oil and Gas Distribution Teehnolog)

机构地区：[1]中国石油大学(北京)/油气管道输送安全国家工程实验室/城市油气输配技术北京市重点实验室

出　　处：《油气储运》2017年第4期409-415,共7页Oil & Gas Storage and Transportation

基　　金：国家自然科学基金重点项目"深水环境下易凝高黏原油-天然气输送系统流动保障基础问题研究";51134006;国家自然科学基金面上项目"油包水型乳状液蜡分子扩散和蜡晶颗粒沉积机理研究";51374224

摘　　要：为了研究管道蜡沉积物蜡晶形态与结构强度的关系,室内制备了不同含蜡比例的胶凝油,模拟现场管道蜡沉积物。借助软件Image J对不同实验条件下拍摄的胶凝油蜡晶显微图像进行处理,确定40℃是该实验蜡晶显微图像的拍摄温度。结果表明:随着胶凝油含蜡量的增大,蜡晶颗粒数与面积分数增大,蜡晶圆度也增大,但长径比减小,且长径比集中分布在1.50~2.00的范围内,表明大部分蜡晶形态呈长棒状。此外,结合胶凝油的屈服应力特性测试,分析蜡晶形态与其结构强度之间的关系:随着含蜡量的增大,蜡晶的边界盒维数增大,屈服应力也随之增大。由此可知:胶凝油内部的蜡晶形态差异是导致其结构强度随含蜡量变化的根本原因,研究结果为今后原油管道的清管工作提供了技术支持。In order to investigate the relation between wax crystal morphology of wax deposit in pipelines and its structural strength, gelling oil with different wax contents was prepared in the lab to simulate wax deposits in the field pipelines. Then, the wax crystal microscopic images which were taken in different experimental conditions were processed by the Image J software. And it is confirmed that these micro images were taken at the temperature of 40 ＊C. It is shown that with the increasing of wax content in gelling oil, the particle quantity, area fraction and roundness of wax crystal increase and its aspect ratio decreases. The aspect ratio is mainly distributed in the range of 1.50-2.00, indicating that the wax crystals are mostly in the shape of long rod. Finally, the relation between wax crystal morphology and its structural strength was analyzed with yield stress behavior test of gelling oil. And it is shown that with the increasing of wax content, the bounding fractal dimension and yield stress of wax crystal increase. It is concluded that the morphnlogic difference of wax crystal inside gelling oil is the fundamental reason why the structural strength of wax crystal varies with the wax content. The research results provide technical support for oil pipeline pigging in the future.

关 键 词：胶凝油 蜡晶形态 边界盒维数 屈服应力 显微特性 Image J 

分 类 号：TE81[石油与天然气工程—油气储运工程]