The Engineering Design And Implementation Of Smoke Concentration On-Line Monitoring System Based On Weighing Method

Existing smoke concentration monitoring method mainly includes both offline and on-line monitoring.Off-line monitoring using the way of manual weighing.But on-line monitoring represented by optical method,is belong to the indirect weighing method,it do not have the characteristics of the smoke quantity traceability.It has influence on environmental protection department to having effective supervision.Therefore,laboratory authorized by shanxi academy of environmental sciences,and design a set of smoke concentration on-line monitoring system based on weighing method,and realize the online and accurate monitoring of ultra-low emissions of smoke concentration in thermal power plants.According to the on-line supervision requirements of the environmental monitoring,and combine the requirements of our country's solid particles concentration measurement in the standard,The thesis is researched from four aspects.(1)The whole design scheme of Smoke concentration of on-line monitoring system.According to the engineering design method of the automatic control,complete the design of system process flow,the design of mechanical structure,the selecte of instrument,the connect of electrical,and establish the general control scheme of the system.(2)Development and design of on-line smoke weighing device.According to the analysis of system requirements,complete the development of on-line smoke weighing device of electromechanical integration,complete design of the embedded circuit by STM32 digital processing core,realize the automatic operation of a series of flexible functions.such as access,transmission,sampling,discarding,weighing,etc.It significantly improves the accuracy of the smoke concentration monitoring and work efficiency.(3)Analysis of the signal processing and control algorithm of the related smoke concentration monitoring.Introduces the calculation method of the smoke concentration in the system,analyzes the signal processing methods of the smoke and dust concentration,such as the weight of smoke,the sampling volume and the oxygen content of the flue gas,etc.And designs the fuzzy algorithm of constant velocity sampling,It Effectively eliminate the measurement error caused by sampling velocity.(4)Software design of smoke concentration on-line monitoring system.Through the cooperation of PLC and STM32,Complete the automatic operation of the device and the real time collection of data.And complete the development of WinCC host computer,realize functions of the real-time display of monitoring data,the manual single step control of the system,the preservation of the data,etc.This smoke concentration on-line monitoring system do the field experiment at Shanxi Ruiguang thermoelectric power plant.After repeated adjustment design scheme,This system basically meet the requirements of smoke monitoring.In the field of environmental monitoring,It solves the needs of automatic weighing method of smoke concentration measurement,effective monitoring for the environmental protection department of coal-fired power plants of smoke concentration and realize the smoke quantity traceability provides basis,has certain practical value.