原油乳化液低场核磁共振测量参数优化与T_2谱特征分析  

Parameter Optimization and T_2 Spectral Analysis for Measuring Crude Oil-water Emulsions by Low Field NMR

作　　者：刘杰 王殿生 崔汪明 LIU Jie;WANG Diansheng;CUI Wangming(Key Laboratory of New Energy Physies ＆ Materials Science in Universities of Shandong College of Seienee, China University of Petroleum, Qingdao 266580, Shandong, Chin)

机构地区：[1]中国石油大学(华东)理学院山东省高校新能源物理与材料科学重点实验室,山东青岛266580

出　　处：《实验室研究与探索》2018年第4期26-31,86,共7页Research and Exploration In Laboratory

基　　金：国家自然科学基金面上项目(51574268);大学生创新训练计划项目(201710425077)

摘　　要：为优化低场核磁共振CPMG自旋回波法检测原油乳化液的测量参数,用原油和蒸馏水配制了含水20.0%的原油乳化液,依次改变各影响参数,测量了相应的T2谱。通过分析T2谱各峰的横向弛豫时间和峰面积随各参数的变化,总结出不同含水原油乳化液的最佳核磁共振测量参数为:重复采样次数取100,重复采样等待时间取8 s,半回波时间取300μs,原油乳化液含水体积分数为C时,回波个数Echo Cnt=11 000+10 000C。在最佳参数下测量了含水20.0%、30.0%、40.0%和50.0%油包水型原油乳化液T2谱,分析了T2谱的基本特征和3个峰的形成机理。A variety of T2 spectra of crude oil-water emulsions with water content 20% prepared in the laboratory are tested in order to optimize the parameters for measuring crude oil-water emulsion by method of the Carr-PurcellMeiboom-Gill（ CPMG） spin echo using low field nuclear magnetic resonance（ NMR）,and the changes of transverse relaxation time and peak area of these T2 spectra are analyzed with various parameters. The results show that optimal parameters for NMR measurement of crude oil-water emulsion with different water content are as follows： NS = 100,TR= 8 000 ms,τ = 300 μs,Echo Cnt = 11 000 ＋ 10 000 C. NMR T2 spectras of W/O emulsions with water content of20%,30%,40% and 50% are respectively measured under the optimal parameters,then characteristics and formation mechanism of the T2 spectras are explained. This study lays foundation for determination of crude oil-water emulsions by low field NMR.

关 键 词：原油 乳化液 核磁共振 参数优化 

分 类 号：TE622.14[石油与天然气工程—油气加工工程]