Portable Gas Pre-conditioning System Design And Use In Combination With Non-dispersive Infrared Analyzer

In recent years,regulations for the prevention and control of air pollution in China have become stricter.The main problem of controlling air pollution is focused on the management and control of flue gas emission in thermal power plants and industrial boilers.Monitoring the emission of stationary pollution source is the key point of environmental governance.Applicability and comparison tests have become important tasks in environment monitoring stations(EMS)for judging the data effectiveness of flue gas.This research study shows that SO2 loss makes Non-Dispersive Infrared(NDIR)analyzer reading inaccurate.This is caused by the dehumidification theory of the condensing cooler.Therefore,an innovative portable gas pre-conditioning system which utilizes a special dry technology called “Nafion dehumidification” was designed.The working principle of Nafion tubing is balancing the water vapor pressure based on the moisture gradient between tubing inside and outside.It can prevent SO2 loss and make NDIR analyzer measurements more accurate and fast.Here is a summary of the main points of the article:(1)After study of drying theory model and characters of Nafion tubing,the design scheme of the portable gas pre-conditioning system based on the Nafion dry technology was proposed,with an introduction to the design structure.(2)According to the system performance requirements,designed a control circuit and selected STM32 processor as main control chip were outlined.The working principle and circuit design of each module are introduced in detail.It mainly includes sensor circuit,Bluetooth circuit,power circuit,memory circuit and display control circuit.(3)Program design of portable gas pre-conditioning system is the primary control program development and acquisition program development.Develop touch screen program used the DGUS platform and variable directly to drive display,achieving functional interaction with STM32 chip.(4)Performance of the portable gas pre-conditioning system is verified under different humidity in laboratory,and then is combined with NDIR analyzer for verifying the system SO2 loss rate.During the on-site comparison testing,compared with CEMS system to verify the system accuracy and reliability.Results show that performance of portable gas pre-conditioning systems which used Nafion dry technology is better than the traditional condensing cooler.Work with NDIR analyzer to measure the SO2 concentration is more accurate,achieved the design target.