光纤气体传感器及其安全工程应用中的关键技术研究

发布时间：2018-04-21 14:20

本文选题：TDLAS + 光纤甲烷传感器　；参考：《山东大学》2016年博士论文

【摘要】：能源是人类生存和发展的重要物质基础,关系着国计民生和国家安全。在能源的开采利用过程中,生产安全成为经济发展中的一项重要课题。近年来,国家对安全生产给予了极大的重视,安全生产事故总量呈下降趋势,但是重特大事故频发且危害严重。在我国煤炭领域,瓦斯和自然发火是煤矿安全生产中的两种主要灾害。针对瓦斯灾害,瓦斯监测监控系统是监测预警的主要手段。当前煤矿监测监控系统的主要问题在于所用的催化燃烧式传感器存在可靠性差,频繁校准,寿命短、量程小等问题；传统红外传感器存在易受背景气体干扰,在高粉尘、高湿度环境无法正常使用,烯烃类气体交叉干扰严重、功耗大等难题；这些传感器已不能适应矿山安全的需求。煤矿自然发火的预测预警主要采取气体指标分析预报办法。传统自然发火所用的痕量气体检测设备主要是色谱分析系统,存在着设备复杂、操作复杂、分析速度慢、不能实现在线监测等问题,限制了其应用范围。随着技术进步,改进的束管系统采用红外分析仪来代替部分色谱分析仪,加快了检测速度,存在的缺陷是测量气体种类少,无法实现存在较大交叉干扰的烯烃类痕量气体检测。因此现有检测技术的缺陷限制了火灾预测预报技术的发展。基于激光光谱技术的光纤气体检测技术具有高分辨率、高选择性、多组分以及低功耗等优点,成为工业有害气体检测的有效工具,能有效解决煤矿安全领域气体检测存在的问题,为煤矿灾害的预测预报提供可靠的数据保障。本论文来源于煤矿安全的实际需求。结合矿山安全的发展现状尤其煤矿安全对气体检测技术的需求,提出用可调谐激光光谱技术来解决煤矿瓦斯和火灾等主要灾害急需的气体传感产品的需求问题。通过调研分析,从仪器整体设计的主要矛盾出发,讨论了光纤气体传感系统中存在的激光器波长漂移导致测量误差的问题,痕量气体检测中光学噪声的干扰问题,以及多组份检测中存在的交叉干扰问题等；提出了一种基于预置零点背景气体的痕量气体检测方法和基于多变量的交叉干扰去除方法；研制了低光学噪声的探测器和光纤耦合长光程气室；开发了光纤甲烷传感器和光纤多组份气体传感器；对传感器性能进行了全面的测试分析;并系统的在煤矿安全领域多个场合的进行了现场试验研究。结果表明研制的光纤气体传感器具有良好的性能,满足煤矿安全领域的应用需求。文章主要研究了以下几个方面的内容：1.通过调研分析,确定了课题研究方向。对激光光谱技术的基础理论知识进行深入研究,通过光谱吸收技术一般理论以及激光吸收光谱的理论分析,为传感器的研制提供了理论依据。2.研制基于激光吸收光谱技术的光纤甲烷传感器。采用直接吸收光谱技术,针对当前光纤甲烷传感器存在的易受光强扰动和激光器漂移造成的稳定性差和测量误差大难题,提出基于参考光路与参考气室的自校准方案,有效消除了激光波长漂移的影响。提出了一种基于最小二乘法的气体校准方法,通过阻尼最小二乘法提高了大量程范围的测量精度。对研制的传感器进行了详细的性能和可靠性测试。3.分析了激光吸收光谱中对微量气体分析中存在的问题,针对光器件中存在的光学噪声,研制了低噪声光电探测器；基于赫里奥特池原理研制了一种光纤耦合的长光程检测气室。对不同的噪声处理算法进行了研究,采用傅里叶变换滤波算法较大抑制了光学干涉噪声,采用卡尔曼滤波算法进行测量结果的噪声滤除,提高了测量稳定性。4. 由于不同光学元件造成的背景波动,限制了系统的探测限的提升。为了进一步提高系统检测限,提出了一种基于预置零点的背景优化痕量气体检测方法,结合最小二乘拟合算法实现了ppm级一氧化碳气体的准确、稳定探测。5.根据多种气体检测的需求,提出了基于波分复用的激光器阵列的多气体检测技术方案。针对不同气体之间测交叉干扰难题,结合多组分检测,提出了基于气体浓度和光谱的多变量分析方法,实现了交叉干扰的有效去除。6.针对煤矿安全的需求,研究了一氧化碳、乙烯、乙炔等痕量气体的检测,进行了系统的测试,实现了气体浓度的高灵敏度高精度检测。7.结合现场需求,开展了光纤气体传感器在煤矿安全领域的应用研究,验证了传感器应用于现场测量的可行性。通过本课题的研究,主要做了以下几个方面的创新性工作：1.研制了一种光纤甲烷传感器。针对当前激光甲烷传感器存在的易受光强扰动和激光器输出波长漂移造成的稳定性差和测量误差大难题,提出基于参考光路与参考气室的自校准方案,有效消除了激光波长的影响。开展了针对光纤甲烷传感器的可靠性试验,为传感器未来的实际应用打下良好的基础。2.分析了光器件中存在的光学干涉噪声,研制了一种低噪声光电探测器,解决了探测器光学噪声引起的检测背景漂移难题。3.基于赫里奥特长光程池原理,研制了一种光纤耦合的长光程检测气室。气室可以做为了独立元件使用,也可以通过光纤进行级联形成更长光程的气室,方便了痕量气体检测技术的研究。4. 提出了一种基于预置零点的背景优化气体检测方案。采用参考气室与传感气室的级联实现了传感信号背景的增强,有效消除了噪声造成的背景波动,结合最小二乘拟合和卡尔曼滤波算法最终实现了ppm级一氧化碳气体的准确稳定探测。5.基于波分复用方式实现了多激光器阵列的多组分气体检测技术,结合多变量分析方法,有效减小气体交叉干扰对检测结果的影响。研制了光纤多组分气体检测仪。
[Abstract]:Energy is an important material basis for the survival and development of human beings, which is related to the national economy and the people's livelihood and national security. In the process of exploitation and utilization of energy, production safety has become an important subject in the economic development. In recent years, the state has paid great attention to the safety production, and the total amount of safety production accidents is declining, but the important event is so frequent. In the field of coal, gas and natural fire are the two main disasters in the safety production of coal mine. In view of the gas disaster, the gas monitoring and monitoring system is the main means of monitoring and early warning. The main problem of the current coal mine monitoring and control system is the poor reliability and frequent calibration of the catalytic combustion sensor used. The traditional infrared sensors are easy to be disturbed by the background gas, can not be used normally in the high dust, high humidity environment, the cross interference of the olefin gas is serious, and the power consumption is big. These sensors are unable to meet the needs of the mine safety. The prediction and early warning of the spontaneous combustion of coal mine mainly adopts the gas index points. The trace gas detection equipment used in traditional natural fire is mainly the chromatographic analysis system, which has complicated equipment, complicated operation, slow analysis speed, can not realize on-line monitoring and so on. It restricts its application range. With the progress of technology, the improved beam tube system adopts infrared analyzer instead of partial chromatograph analyzer. The detection speed has been speeded up, and the defect is that there are few kinds of gas and can not realize trace gas detection with large cross interference. Therefore, the defects of the existing detection technology restrict the development of fire prediction and prediction technology. The optical fiber gas detection technology based on laser spectroscopy has high resolution, high selectivity and multi component. With the advantages of low power consumption and so on, it has become an effective tool for the detection of industrial harmful gas. It can effectively solve the existing problems of gas detection in the field of coal mine safety and provide reliable data guarantee for the prediction and prediction of coal mine disasters. This paper is derived from the actual demand of coal mine safety. The demand of the technology of tunable laser spectroscopy is proposed to solve the demand problem of gas sensing products which are urgently needed in coal mine gas and fire disaster. The problem of measurement error caused by laser wavelength drift in the optical fiber gas sensing system is discussed by the main contradiction of the overall design of the instrument. The interference of optical noise in trace gas detection, as well as the cross interference in multicomponent detection, etc., a trace gas detection method based on the preset zero background gas and the cross interference removal method based on multi variable is proposed, and a low optical noise detector and a optical fiber coupled long range gas chamber are developed. The fiber optic methane sensor and optical fiber multi component gas sensor were sent, and the performance of the sensor was tested and analyzed. The field test was carried out on several occasions in the field of coal mine safety. The results show that the developed fiber gas sensor has good performance and meets the application demand in the field of coal mine safety. The main contents are as follows: 1. through investigation and analysis, the research direction of the subject is determined. The basic theoretical knowledge of laser spectroscopy is deeply studied. Through the general theory of spectral absorption technology and the theoretical analysis of the laser absorption spectrum, the theoretical basis of the research of the sensor is provided by.2.. Direct absorption spectroscopy is used to solve the problem of poor stability and measurement error caused by light intensity disturbance and laser drift in current fiber optic methane sensor. A self calibration case based on reference light path and reference gas chamber is proposed, which effectively eliminates the influence of laser wavelength drift. A gas calibration method based on least square method is developed, and the measurement accuracy of a large range of range is improved by the damped least square method. A detailed performance and reliability test for the developed sensor is carried out to analyze the problems in the analysis of the trace gas in the laser absorption spectrum and the optical noise in the optical device,.3.. A low noise photodetector is developed, and a fiber coupled long path detection gas chamber is developed based on the principle of the herb pool. The different noise processing algorithms are studied. The Fourier transform filtering algorithm is used to suppress the optical interference noise, and the Calman filter algorithm is used to filter the noise of the measurement results. In order to further improve the detection limit of the system, a background optimization trace gas detection method based on the preset zero point is proposed in order to further improve the detection limit of the system. In order to further improve the detection limit of the system, a method based on the least square fitting algorithm is proposed to achieve the accuracy of the carbon monoxide gas of the ppm level and the stable detection of.5, in order to further improve the detection limit of the system. According to the demand of multi gas detection, a multi gas detection scheme for laser array based on wavelength division multiplexing is proposed. In view of the cross interference problem between different gases and multi component detection, a multivariable analysis method based on gas concentration and spectrum is proposed, which realizes the effective removal of.6. against coal mine safety. The detection of trace gases such as carbon monoxide, ethylene, acetylene and other trace gases was studied. The high sensitivity and high precision detection of.7. combined with the field requirement was realized. The application of optical fiber gas sensor in the field of coal mine safety was carried out, and the feasibility of the sensor used in the field measurement was verified. The research of the problem is made in the following aspects: 1. developing a fiber optic methane sensor. Aiming at the difficulty of the stability and measurement error caused by the light intensity disturbance and the laser output wavelength drift in the current laser methane sensor, a self calibration scheme based on the reference light path and the reference gas chamber is proposed. The effect of laser wavelength is eliminated effectively. The reliability test for optical fiber methane sensor is carried out. The optical interference noise in the optical device is analyzed for the practical application of the sensor in the future. A low noise photodetector is developed, which solves the difficulty of detecting background drift caused by the optical noise of the detector. Problem.3. based on the principle of the long light path pool, a fiber coupled long path detection gas chamber is developed. The gas chamber can be used for independent components and can be cascaded through fiber to form a gas chamber with longer light range. The study of trace gas detection technology is convenient..4. proposed a background optimized gas examination based on the preset zero point. Using the cascade of reference gas chamber and sensing chamber to enhance the background of the sensing signal, the background fluctuation caused by noise is eliminated effectively. The accurate and stable detection of PPM carbon monoxide gas is realized by the least square fitting and Calman filter algorithm, and the multi laser array is realized based on the wavelength division multiplexing mode of.5.. Multi component gas detection technology, combined with multivariable analysis method, effectively reduces the influence of gas cross interference on the detection results. A multi component gas detector is developed.

【学位授予单位】：山东大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：TP212

【相似文献】