Hello everyone! Today, we are going to talk about the hazards of impurities in water on plate heat exchanger I believe that many people are no strangers to heat exchangers, but do you know what hazards of impurities in water on heat exchangers? Here let me take you to find out.
First of all, we need to understand the role of the heat exchanger. Heat exchanger is an indispensable part of the air conditioning, heating and other equipment, it is through the transfer of heat, to achieve the exchange of heat and cold. And plate heat exchanger is widely used in various occasions because of its high efficiency and compactness. However, the presence of impurities in the water makes plate heat exchangers face many challenges.
Water impurities in the "three sins"
1. Calcium salts: Calcium salts are the main components that cause heat exchanger scaling. Scale not only reduces the efficiency of heat exchange, but also may lead to equipment damage. Especially CaSO4, it is a hard, crystalline fine scale, easy to form loose slag on the surface of the heat exchanger, affecting the operation of the equipment.
2. magnesium salt: magnesium salt is thermally decomposed in water, generating Mg(OH)2 precipitation and forming slag scale. In addition, MgCl2 and MgSO4 dissolved in water will also cause acidic corrosion of the metal wall. 3.
3. Sodium salt: Although NaCl does not generate scale, but it will accelerate the corrosion of metal wall; Na2SO4 content is too high, it will form salt after evaporator, which affects the safe operation; NaHCO3 decomposes under the action of temperature and pressure, which leads to the damage of metal grain.
In addition, the hazards of dissolved oxygen gas should not be ignored. Oxygen is the main cause of heat exchanger corrosion, it makes the metal surface Fe (OH) 3 precipitation, accelerate the corrosion process.
Impurities present in a colloidal state
1. Iron compounds: Iron scale affects the heat exchange effect and makes the water yellow.
2. microorganisms: microorganisms multiply in large numbers in the cooling circulating water and tend to block the plate channels, leading to metal corrosion.
3. sludge: dust in the air and suspended matter in the supplementary water will be deposited in the heat exchanger, affecting the operation of the equipment.
4. Sticky scale: microbial secretions and water sediment, corrosion products, fungal and algal debris bonding, attached to the heat exchanger wall, causing corrosion.
