Spectroscopic imaging of deposition of asphaltenes from crude oil under flow
Spectroscopic imaging of deposition of asphaltenes from crude oil under flow
复制标题
流动下原油中沥青质沉积的光谱成像
DOI：
10.1016/j.petrol.2019.106205
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发表时间：
2019
影响因子：
--
通讯作者：
O. Martyanov
中科院分区：
文献类型：
--
作者：
A. Shalygin;I. Kozhevnikov;S. Kazarian;O. Martyanov
我们展示了，第一次，应用FTIR光谱成像方法原位监测石油沥青质的沉淀过程中，诱导下使用微流控装置流动的正庚烷。研究了沥青质在苯中的质量分数为5%的溶液中，正庚烷流动诱导沥青质的聚集，随后沉淀并形成沉积物。FTIR光谱方法与阵列检测器使我们能够评估的化学成分的空间分布和它们的量在系统中，并显示聚集体形成的过程与几微米的空间分辨率。该化学成像技术表明，庚烷的流动导致的非平衡状态时，局部含量的絮凝剂达到所需的阈值量的沥青质聚集。庚烷向苯中扩散的相对缓慢的过程诱导沥青质聚集，随后它们沉淀和压实。庚烷流动下沥青质的快速聚集过程导致形成牢固地固定在表面上的存款，而庚烷向苯中扩散过程中形成的沉淀物可以容易地从通道中带走。沉积物的FTIR光谱图像显示了在微流体通道中庚烷流动方向上沉淀的沥青质的空间不均匀性，这反映在它们的不同化学组成和不同官能团（CH 2-CH 3、C双键O、S双键O）的存在上。特别地，发现不同类型和不同CH 2/CH 3比的沥青质逐渐开始在正庚烷流动的方向上沉淀。所获得的数据表明絮凝剂的局部浓度以及沥青质聚集的系统的局部特征和流动状态中的整体沉淀过程的重要性。
We demonstrate, for the first time, the application of FTIR spectroscopic imaging approach in situ to monitor the precipitation process of oil asphaltenes, induced by n-heptane under flow using microfluidic devices. The aggregation of asphaltenes induced by n-heptane flow with subsequent precipitation and formation of the deposits was studied for solution containing 5 wt % of asphaltenes in benzene. The FTIR spectroscopic approach with an array detector allowed us to assess the spatial distribution of the chemical components and their amounts in the system and display the process of aggregates formation with a spatial resolution of few micrometres. This chemical imaging technique shows that the flow of heptane results in non-equilibrium condition when the local content of the flocculants reaches the threshold amount needed for the asphaltenes aggregation. The relatively slow process of heptane diffusion into the benzene induces the asphaltenes aggregation followed by their precipitation and compaction. Fast asphaltene aggregation process under heptane flow leads to the formation of the deposit firmly fixed to the surface, while the precipitates formed during the diffusion process of heptane into the benzene can be easily taken from the channel. The FTIR spectroscopic imaging of the deposits formed revealed the spatial inhomogeneity of the precipitated asphaltenes in the direction of the heptane flow in microfluidic channel which is reflected in their different chemical composition and the presence of different functional groups (CH2–CH3, Cdouble bondO, Sdouble bondO). In particular, it was found that asphaltenes of different types and different CH2/CH3ratios gradually start to precipitate in the direction of n-heptane flow. The data obtained demonstrate the importance of local concentration of flocculants as well as local characteristics of the system for asphaltenes aggregation, and overall precipitation process in flow regime.
影响因子：
5.3
作者：
Feng H. Tay;S. Kazarian
通讯作者：
Feng H. Tay;S. Kazarian
影响因子：
4.5
作者：
Chmelik, Christian;Liebau, Michael;Kaerger, Joerg
通讯作者：
Kaerger, Joerg