基于双楔形扫描镜的甲烷气体光谱成像方法
Methane gas spectral imaging method based on dual wedge scanning mirrors
王夏春 1张志荣 2蔡永军 3孙鹏帅 4庞涛 4夏滑 4吴边 4郭强4
作者信息
- 1. 中国科学技术大学研究生院科学岛分院,合肥 230026;中国科学院合肥物质科学研究院安徽光学精密机械研究所,光子器件与材料安徽省重点实验室,合肥 230031
- 2. 中国科学院合肥物质科学研究院安徽光学精密机械研究所,光子器件与材料安徽省重点实验室,合肥 230031;中国科学院合肥物质科学研究院安徽光学精密机械研究所,中国科学院环境光学与技术重点实验室,合肥 230031;国防科技大学,先进激光技术安徽省实验室,合肥 230037
- 3. 国家管网集团科学技术研究总院分公司,廊坊 065000
- 4. 中国科学院合肥物质科学研究院安徽光学精密机械研究所,光子器件与材料安徽省重点实验室,合肥 230031
- 折叠
摘要
随着我国油气管道铺设数量的增加,对管道的维护工作也需予以更多的重视.目前,在油气输送站场内,主要采用人工巡检、对射式和云台式检测设备来检测天然气泄漏.但是这些方法存在响应度差、检测区域受限、泄漏点定位较慢等问题.为了满足对油气管道泄漏实时监测和快速定位的需求,本文设计了一种快速、精确控制的双楔形扫描镜系统,结合可调谐半导体激光吸收光谱技术,使得气体测量由原来的点测量转换为面测量.通过反解迭代优化算法,控制楔形镜的转角获得高效均匀的光束扫描轨迹,并将激光束的偏转方向及检测位置与对应的甲烷浓度信息相融合,构建了包含有位置信息的甲烷浓度数据,实现甲烷气体的光谱成像.实验中为了定量验证测量准确度及空间分辨率,通过标准气袋模拟甲烷泄漏分布,结果表明系统的成像浓度检测限小于 500 ppm·m(1 ppm=10-6),位置分辨率小于 6 cm.同时该方法可以依据油气站场的测量距离调节扫描步进节点,从而实现成像分辨率的可调节,该成像方法为精确定位甲烷气体泄漏提供了新的思路.
Abstract
With the increase in the number of oil and gas pipelines laid in China,more attention needs to be paid to pipeline maintenance work.At present,the main methods of detecting natural gas leaks in oil and gas transmission stations include manual inspections,opposing natural gas detection equipment,and cloud desktop natural gas detection equipment.Hand held natural gas detection equipment is used for manual inspection,which requires regular manual inspection.However,the response speed is poor and gas leaks cannot be detected in a timely manner.The opposed laser gas detection method can only detect the presence of gas on the beam path.If a larger area of leakage detection is desired,more equipment needs to be installed,resulting in a greatly increase in hardware costs.The existing cloud desktop laser gas detection method controls the deflection of the laser beam through the cloud platform to achieve leak detection at various points in the area to be tested.However,the rotation speed of the cloud platform is slow,and a complete detection cycle takes dozens of minutes,and only the presence of gas can be detected.For accurate leak location,manual on-site survey is also required to further determine the leak location.In order to meet the needs of the real-time monitoring and rapid positioning of oil and gas pipeline leaks,in this work,a fast and accurately controlled dual wedge scanning mirror system is designed,which combines tunable semiconductor laser absorption spectroscopy technology to convert the gas measurement laser beam from point measurement to surface measurement,thereby obtaining the two-dimensional distribution of gas,which is conducive to subsequent analysis and positioning of gas leakage sources.By using the inverse solution iterative optimization algorithm,the angle of the wedge mirror is controlled to obtain an efficient and uniform beam scanning trajectory.The deflection direction and detection position of the laser beam are fused with the corresponding methane concentration information,and a methane concentration data containing position information is constructed.In order to quantitatively verify the measurement accuracy and spatial resolution in the experiment,a standard air bag is used to simulate the methane leakage distribution.The results show that the minimum detection limit of the system can be lower than 5×10-4 m,and the spatial resolution can be less than 6 cm.At the same time,this method can adjust the scanning step node based on the measurement distance of the oil from gas station,thereby achieving adjustable imaging resolution.This imaging method provides a new idea for accurately positioning and detecting the methane leakage location and amount.
关键词
激光吸收光谱/甲烷气体检测/双楔形扫描镜/气体成像Key words
tunable diode laser absorption spectroscopy/methane gas detection/double wedge scanning mirror/gas imaging引用本文复制引用
基金项目
国家重点研发计划(2022YFB3207601)
国家重点研发计划(2021YFB3201904)
国家自然科学基金(11874364)
国家自然科学基金(41877311)
国家自然科学基金(42005107)
中国科学院合肥研究院"火花"基金(YZJJ2022QN02)
安徽省教育厅优秀青年科学基金(2022AH020098)
出版年
2024
国家科技期刊平台
NSTL
万方数据