Why is the scale on the steam generator? How is the scale formed?
If the water quality is hardness, after the water is heated and evaporated, the impurities that cannot be evaporated remain in the steam generator, and gradually become saturated.
The main components of scale are calcium carbonate, magnesium carbonate, calcium sulfate, magnesium sulfate, calcium chloride, magnesium chloride, etc. These substances are originally soluble in water. During the operation of the steam generator, their physical and chemical properties change. For example, the temperature rises, which reduces the solubility of these substances. It is easy to crystallize on the heated surface to form water slag; After evaporation, the salts in the water are gradually concentrated, and chemical transformation occurs at the same time to form scale.
What is the harm of scale to the steam generator?
1. reduce steam generator thermal efficiency
The thermal conductivity of scale is generally only a few tenths of that of metal, which will have a great impact on the thermal efficiency and evaporation capacity of the steam generator.
2.Waste fuel
Because the thermal conductivity of scale is tens to hundreds of times smaller than that of steel. Therefore, when the boiler is scaled, the heat transfer performance is deteriorated, the heat released by the fuel combustion cannot be effectively transferred to the water, and a large amount of heat is taken away by the flue gas, resulting in an increase in the exhaust gas temperature and the exhaust gas. The heat loss increases and the thermal efficiency decreases. In this case, in order to ensure the parameters of the boiler, it is necessary to add more fuel to increase the temperature of the furnace and the temperature of the flue gas, thus causing waste of fuel.
3.Affect the safe operation and reduce the service life of the steam generator
The scale on the surface of the heating pipe is uneven in thickness and thickness, and local overheating is more serious, which will cause deformation, bulging, cracks, and even blasting of the pipe wall at the scaled part, which seriously affects production safety. Seriously affect the safe operation and service life of the steam generator. Metal corrosion is carried to the steam liner by water, and after being heated, scale will form again. This vicious cycle will quickly damage the steam generator components.
Factory suggestion:
Steam generators must be equipped with water treatment equipment.
