Design And Realization Of Water Quality Detector Used In Circulating Cooling Water System

The water quality hardening of circulating cooling water will make cooling system suffer scaling and plugging,causing damage to equipment and significant economic losses.The parameters of circulating water such as electrical conductivity and p H value directly affect the scaling speed of the circulation system,which are also the important indexes to evaluate the energy-saving and environmental-protection performance of water resources in the system.No matter whether from the perspective of ensuring the stable operation of circulating cooling water system or from the perspective of saving scarce water resources in the country,the high-precision and automatic water quality detector is of great research value.To improve the precision and stability of water quality detector,developed a CORTEX-M3-based circulating water quality detection device.The applications of comparative measurement method and Kalman filtering in detector were explored to eliminate system error and improve the detection precision and stability.The main findings and achievements of this paper are as follows:(1)By studying the research status of water quality detection at home and abroad and combining with the development of water quality detector and the actual needs of enterprises and national standards,the detection scheme for water quality parameters of circulating cooling water was established.(2)For main detection parameters such as conductivity and pH value,it started from their sensor structures and detection principles,the influence factors and characteristics of electrical conductivity and pH value in the process of detection were analyzed in detail,and the solutions were put forward.(3)For the main error sources in the circuit detection,comparative measurement method and the Kalman filtering method were introduced for the first time to be applied in parameter detection,thus improving the detection precision.(4)Based on the detection scheme for water quality parameters of circulating cooling water,the design of the hardware device for water quality detection of circulating cooling water was completed,and the circuit design method with increased detection parameter precision was analyzed.Meanwhile,the system initialization,acquisition and calculation,self-recovery,communication and other software programs were further completed to fully realize the function of the instrument.(5)The precision and repeatability experiment of the detection device were conducted,the precision,stability and reliability of the instrument were verified.Through the comparative analysis with XR-620 CTD+ water quality instrument and PHS-25-type pH detector,it was proved that the water quality monitoring device of circulating cooling water based on comparative measurement method and Kalman filtering processing method was effective.The water quality detector developed in this paper is able to achieve the automatic,high-precision and stable detection goals in the circulating cooling water system.At the same time,it is the first time to explore the application of comparative measurement method and Kalman filtering in water quality detector with good experimental results.The research on the water quality detector not only provides the data reference for the scaling and water-saving of circulating cooling water,but also lays a foundation for scale inhibition control.