便携式气相色谱仪的开发与应用研究

发布时间：2018-05-10 16:56

  本文选题：便携式气相色谱仪 + COMSOL　； 参考：《哈尔滨工业大学》2015年硕士论文

【摘要】：气相色谱仪是分析领域最重要的通用仪器之一,是分离和检测样品的重要工具。然而,传统气相色谱仪因其体积较大、重量较重、分析时间较长等不利因素存在,限制了其在现场分析检测中的应用。与传统的实验室气相色谱仪相比,便携式气相色谱仪因其分析速度较快、体积较小、重量较轻等优势在现场快速分析检测领域拥有着广阔的市场需求。然而,由于国内技术基础比较薄弱、科研储配人才较少、相关研究起步较晚等一系列原因,导致国内的便携式气相色谱仪市场一直被安捷伦等国外的分析仪器生产商所垄断。为打破国外的技术垄断,开发出拥有自主知识产权的便携式气相色谱仪,本文进行了便携式气相色谱仪的开发和应用研究,研制出了一种体积小、重量轻、分析速度快的便携式气相色谱分析仪器,以应对各种条件下现场快速分析检测的需求。首先,本文利用COMSOL Multiphysics数值仿真软件对气化室的气流场和氢火焰离子化检测器的静电场进行了建模仿真。在模拟结果的指导下,对气化室和氢火焰离子化检测器的几何模型进行了优化设计,使得气化室中的死体积区域大幅缩减,氢火焰离子化检测器的带电离子收集效率大幅提升。然后,基于PID控制原理进行了温度控制模块和气路控制模块的设计。采用实验室开发的恒流源测温电路和小功率加热电路配合基于Lab VIEW软件编写的PID温度控制程序完成了温度控制模块的设计,温控精度可达0.1℃。而后采用商品化的电子压力控制器配合基于Lab VIEW软件编写的PID压力控制程序实现了对压力和流量的精确控制。最后,在各个模块研究的基础上进行了便携式气相色谱仪装置的整体搭建,并对搭建好的便携式气相色谱仪装置进行了性能测试。初步测试结果显示,自制便携式气相色谱仪检出限为1.861×10-8 g/s,定性重复性为2.152%,定量重复性为10.401%,在100 mg/L-2000 mg/L的浓度范围内表现出了良好的线性关系,其相关系数达到了0.9966。而后,应用自制的便携式气相色谱仪结合膜萃取技术建立了海水中甲苯的快速检测方法。检测结果表明,通过膜萃取样品预处理方法的运用,使得海水中甲苯可检测的浓度值达到了1 mg/L,间接地提高了自制便携式气相色谱仪装置对海水中甲苯的检测范围。
[Abstract]:Gas chromatograph is one of the most important universal instruments in the field of analysis. It is an important tool for the separation and detection of samples. However, because of its large volume, heavy weight and long analysis time, the traditional gas chromatograph has limited its application in field analysis and detection. Compared with the traditional laboratory gas chromatograph, the portable gas chromatograph has a broad market demand in the field of rapid analysis and detection because of its advantages of faster analysis speed, smaller volume and lighter weight. However, the domestic market of portable gas chromatograph has been monopolized by the manufacturers of analytical instruments, such as Agilent and other foreign manufacturers, due to a series of reasons, such as weak technical foundation, less talents in scientific research storage and matching, and the late start of related research. In order to break the technology monopoly of foreign countries and develop a portable gas chromatograph with independent intellectual property rights, the development and application of the portable gas chromatograph have been carried out in this paper. A kind of portable gas chromatograph has been developed, which is small in volume and light in weight. The portable gas chromatographic analysis instrument with high speed is used to meet the demand of field analysis and detection under various conditions. Firstly, the numerical simulation software COMSOL Multiphysics is used to model the gas flow field in the gasification chamber and the electrostatic field in the hydrogen flame ionization detector. Under the guidance of the simulation results, the geometric models of the gasification chamber and the hydrogen flame ionization detector are optimized. The dead volume region in the gasification chamber is greatly reduced, and the charged ion collection efficiency of the hydrogen flame ionization detector is greatly improved. Then, temperature control module and gas path control module are designed based on PID control principle. The temperature control module is designed by using the constant current source temperature measuring circuit developed in the laboratory and the low power heating circuit and the PID temperature control program based on Lab VIEW software. The temperature control precision can reach 0.1 鈩，

本文编号：1870113