降凝剂对原油中蜡晶形态的影响  

INFLUENCE OF POUR POINT DEPRESSANT ON WAX CRYSTAL MORPHOLOGY OF CRUDE OIL

作　　者：张金俊[1] 关建宁[1] 宋娜[1] 周健[2] 姚成[1] 

机构地区：[1]南京工业大学理学院,江苏南京210009 [2]中国石化石油化工科学研究院,北京100083

出　　处：《石油学报（石油加工）》2010年第1期27-30,共4页Acta Petrolei Sinica(Petroleum Processing Section)

基　　金：南京工业大学博士创新基金项目(BSCX200813)资助

摘　　要：采用偏光显微镜观察降凝剂（PPD）在不同添加量下原油蜡晶形态的变化；采用图像分析软件统计分析蜡晶的数目、颗粒直径等参数，实现了蜡晶大小及其分布特征的量化描述。结果表明，随着降凝剂的加入，原油中的蜡晶由不规则的大的片状、棒状形态逐渐变成大量小的、分散较均匀的结晶形态，原先占主导地位的大直径（9～13μm）蜡晶的质量分数由67．5％下降至0．01％，小直径（2～5μm）蜡晶的质量分数由8．5％上升至95．6％；降凝剂的加入阻碍了蜡晶相互连接搭桥成网，体系能量降低，形成空间网络结构的可能性较小，原油低温流变性得到明显改善。通过非线性回归可确定降凝剂添加量、蜡晶平均直径、降凝幅度的关系，其结果与实验结果吻合。Variety of wax crystal morphology in crude oil under different addition amount of pour point depressant （PPD） was observed by micropolariscop and the number and diameter of wax crystals were analyzed by image software to realize quantitative description of wax crystals size and distribution. With the OMA addition amount increased, the wax crystals of crude oil became shorter and smaller with even size, and well dispersed from irregular, flake and rod-like. The content of wax crystals with the diameter of 2-5 μm increased from 8.5% to 95.6%, while the content of wax crystals with the diameter of 9-13 μm decreased from 67.5% to 0.01%. It was shown that the PPD could inhibit the formation of wax crystals network, thus the system energy decreased and the possibility of forming space net structure became less, and rheologic behavior was improved. The relation of PPD dosage added in crude oil with average diameter of wax crystals and magnitude of pour point depression could be determined by nonlinear fitting, which was in accordance with the testing results.

关 键 词：蜡晶 直径 添加量 降凝幅度 

分 类 号：TE624.8[石油与天然气工程—油气加工工程]