石油沥青质聚沉的微观机理  

Micromechanism of petroleum asphaltene aggregation

作　　者：卢贵武[1] 李英峰[1] 宋辉[2] 于迎辉[1] 王春雷[3] 

机构地区：[1]中国石油大学北京数理系 [2]长庆石油勘探局第二采油技术服务处工艺所 [3]山东大学物理与微电子学院

出　　处：《石油勘探与开发》2008年第1期67-72,共6页Petroleum Exploration and Development

基　　金：中国石油天然气集团公司石油科技中青年创新基金(CNPC04E7038、CNPC2006-2008)

摘　　要：应用分子力学和分子动力学方法构建了溶剂-沥青质分子相互作用体系的周期性结构模型,研究硝基苯、喹啉、吡啶、1-甲基萘、二溴甲烷、苯6中不同溶剂对沥青质聚沉过程的影响。通过对沥青质聚合体构型和其分子间相互作用能的分析,确定了沥青质聚沉的主要驱动力,讨论了常温和加热条件下不同溶剂对沥青质聚合体稳定性的影响机制。研究表明,范德华相互作用能在沥青质聚合体内占据主导地位,静电相互作用能相对较小;分子间的π-π相互作用是促使沥青质聚合最主要的驱动力,杂原子的存在可能是促使沥青质分子聚合的主要原因之一;溶剂苯和硝基苯对沥青质聚沉有显著的抑制或解聚作用,可作为沥青质沉积的抑制剂和清除剂。The periodic molecular structure model of solvent-asphaltene system is constructed using molecular mechanical and molecular dynamical methods. The influences of six solvents （ Nitrobenzene, Quinoline, Pyridine, 1- methylnaphthalene, Dibromomethane, Benzene） on the aggregate process of asphaltene molecules are investigated at normal temperature and higher temperatures. According to the analyses of structure and energy, the main interaction for the asphaltene aggregate is determined, and the influencing mechanism for the asphaltene stability in different solvents is discussed at 300K and 573K temperatures. It is found that VDW interaction plays an important role in the stability of the asphaltene aggregate. The electrostatic interaction is small compared to the VDW interaction. And the π-π interaction is the leading force for the aggregation of asphaltene molecules. The presence of heteroatom might be the major reason for the asphaltene polymerization. Benzene and nitrobenzene have a prominent inhibiting or disassociating effect on the asphaltene aggregation, and they can be chosen as inhibiting and scavenging agents.

关 键 词：沥青质聚沉 分子力学 分子动力学 相互作用能 

分 类 号：TE311[石油与天然气工程—油气田开发工程]