Plate heat exchanger maintenance-analysis on the cause of fouling heat exchanger_
923 Plate Heat Exchanger Maintenance-Analysis of the causes of fouling heat exchangers, the water cycle system often has faults such as fouling, erosion and biological slime, and the heating system is in the process of daily operation. During the maintenance of the plate heat exchanger, it was found that the normal operation of the system was seriously affected, the operating cost was increased, the normal service life of the heating equipment was shortened, and the equipment was scrapped in advance. These faults are mainly caused by the following reasons: 1. The heating system generally uses untreated tap water containing a large amount of scale-forming ions such as Ca2+Mg2+. These scale-forming ions are easily removed when the water temperature rises or evaporation is concentrated. The water is saturated and deposited on the metal surface of the boiler, heat exchanger and pipe network to form scale. 2. After the silt and various bacteria, algae and microorganisms in the feed water enter the water system, because the temperature is suitable for the growth and reproduction of microorganisms, a large amount of microbial sludge is produced in the system, which adheres to the radiator tube and mixes with the scale to form biological fouling . 3. Dissolved oxygen and salt in the water will cause oxygen and chemical corrosion to the metal material of the heating system. Because the heating system is composed of a variety of materials in water containing a large amount of electrolyte salts, galvanic couples and corrosion batteries are formed between different metals, thereby causing electrochemical corrosion to the system metals. Scaling and biological sludge can also cause under-scaling and microbial corrosion of metals. The hazards of scaling and erosion to the heating system 1. The energy consumption is greatly increased. The heat transfer efficiency of boilers and heat exchangers is reduced, the area of u200bu200bcirculation water is reduced, and the resistance to flow is increased, which leads to a substantial increase in energy consumption and heating costs. 2. The working efficiency of the system decreases, which affects the heat exchange efficiency of the heating system after scaling. The temperature of the hot water outlet decreases, the return water temperature increases, and the temperature difference between the inlet and outlet water decreases. As a result, the heating efficiency in winter decreases and the house temperature is low. 3. Shorten the service life of the equipment and increase the cost of equipment maintenance. Scaling and muddy faults affect the normal operation of the system. Periodic cleaning and inspection are required, which greatly increases the cost of equipment inspection and cleaning. This cost is much higher than the normal maintenance cost of the system. Due to corrosion, the metal materials of the heating water system are damaged. This damage will shorten the service life of heat exchangers, boilers and other equipment and pipelines, causing heating water pipelines and terminal equipment to rupture and leak, directly damage the room decoration materials, and increase The cost of maintenance and decoration will lead to early scrapping of boilers and heat exchangers in severe cases.