基于微流控的重油结焦前体物可视化定量表征新方法

The problem of coking restricts the operation cycle, energy consumption level, and operation safety of refining units in the process of heavy oil processing. The coking precursor is the "seed" of coke in the industrial equipments. The shape characteristics of the "seed", such as particle size, are the key factors that influence the sedimentary coking performance. Due to the quantitative characterization method of coking precursor is lack, this project will develop a new visual method for the quantitative characterization of coking precursor. (1) A microfluidic analysis system will be developed. The flow characteristics in the microfluidic chip will be studied by experiment, theoretical analysis and numerical simulation. (2) A digital processing method for the microscopic image will be established to calculate the particle concentration. Furthermore, the effect of overlapping and adhesion on the test results will be solved by the optimization of system parameters and image cut algorithm. (3) The accuracy, repeatability and reproducibility of this method will be tested with a standard matter. The uncertainty analysis will also be carried out. This research project will provide a new research method for the quantitative understanding the shape characteristics of coking precursor and coking mechanism.

重质油加工过程中的结焦问题是制约炼油装置运行周期、能耗水平和操作安全的重要瓶颈。结焦前体物是引起设备结焦的“种子”，其外形特征是影响其沉积结焦性能的重要因素。鉴于重油结焦前体物外形特征缺乏定量化的表征方法，本项目将建立一种可视化的重油结焦前体物定量表征新方法。（1）组建微流控分析系统，采用实验研究、理论分析与数值模拟相结合的方法，重点研究微流控芯片内流动特性。（2）建立数字显微图像处理方法，实现颗粒浓度参数计算，通过优化系统参数和图像切割算法，解决重叠和粘连对测试结果影响。（3）以标准物质为样本，检验测试结果的准确性、重复性和再现性，并进行不确定度分析。项目研究成果将为定量化认识重油结焦前体物外形特征，深入认识结焦机理，提供新的研究方法。

重油加工过程中的结焦问题是制约炼油装置运行周期、能耗水平和操作安全的重要瓶颈。结焦前驱物是引起设备表面结焦的“种子”，“种子”的粒度分布、粒形等外形特征是影响其沉积结焦性能的关键因素。本项目基于可控液膜显微图像处理技术，开发了一种可视化的重油结焦前驱物定量表征新方法，实现了结焦前驱物总体收率与外形参数（粒度分布、粒形等）的快速定量表征。采用随机抽样统计理论确定图像最小样本数，解决了单张显微图像代表性差的问题。该方法具有分析过程简单、样品用量少、重复性好、检测精度高等优点，可适用于低透光率油品的颗粒物检测，并能同时油品中甲苯不溶物收率、粒度分布和形状因数等信息，并具有良好的重复性和可靠性，平行实验相对标准差结果显示，其检测精度可达到0.1%。项目研究成果为定量化认识重油结焦前驱物外形特征，深入研究结焦机理，提供了新的研究方法。该方法已应用于减压深拔原料浅度热缩合反应特性评价，并可推广应用于催化油浆、焦化蜡油、废润滑油等油品中的颗粒物检测。