Research On The Laser Detection Of Water Content In Natural Gas And The Influence Of High Temperature Radiation

With the global energy shortage and the increasing awareness of environmental protection,natural gas as an efficient clean energy is widely used in daily life and industrial production.Natural gas needs to be purified before centralized transportation,and the pipeline has residual water due to improper purification and other operation reasons.On the one hand,water vapor will affect the calorific value and quality of natural gas;on the other hand,it will cause ice blockage and corrosion of pipeline,and even lead to pipeline leakage and explosion,which poses a great threat to workers and production safety.Therefore,it is necessary to monitor the water vapor of natural gas in the transmission pipeline in real time to ensure the safe operation of natural gas gathering and transmission pipeline.Based on the research framework of spectroscopy absorption principle and radiation transmission basic theory,this paper analyzes the spectral absorption principle and spectral absorption characteristics of water bearing natural gas in pipeline transportation.Based on the TDLAS technology,the relevant technical problems of water vapor concentration laser detection are studied.At the same time,the structure of stray radiation suppression is designed and simulated.The main research contents are as follows:(1)Based on the absorption principle of spectroscopy and Beer-Lambert law,We derive the inversion model of gas concentration,determine the central absorption wavelength and absorption spectral line of water vapor,analyze the influence mechanism of temperature on the absorption spectral line strength of water vapor,and establish the correlation model of temperature-concentration coupling variable water vapor spectral absorption.(2)Using Trace Pro optical simulation software,we analyzed the transmission characteristics of water vapor laser in different concentration pipeline transportation.Based on TDLAS technology,we built an experimental platform for water vapor laser detection in high temperature environment,and proposed a concentration inversion correction method for water vapor concentration laser detection in temperature dynamic environment.(3)We analyzed the influence of ambient temperature and high temperature on the transmission optical path of laser detection of water vapor of natural gas.Based on the stray radiation produced by the high temperature environment,we designed a combined stray radiation suppression structure of the shield,the baffle ring and the extinction thread,and compared it with the conventional detection optical path.The results show that the stray radiation suppression structure can effectively improve the recognition ability of the optical path system to the target signal.Based on the research background of the laser detection of the water content in the pipeline natural gas,the laser detection experiment in the high temperature environment is carried out based on the TDLAS technology,and designed a stray radiation suppression structure to improve the receiving efficiency of the detector,which provides a reference for the future development of on-line detection technology of water vapor in natural gas.