Welcome to official website of Liaoning Tongda Heat Exchanger Equipment Manufacturing Co., Ltd!
  • Consultation hotline:024-75166966
location: 首页>English>News information>Company news

Influence of scaling on spiral plate heat exchanger and its treatment

Aug 12,2022 Number of readings: Column:Company news

There are many kinds of heat exchangers, but no matter which type of heat exchanger, after running for a period of time, a layer of white scale will adhere to the inner and outer walls of the heat exchanger. The main reason for the formation of scale is that water contains calcium and magnesium salts with low solubility. These salts have common characteristics, and their solubility decreases with the increase of water temperature, and they become unbearable salts.


Influence of heat exchanger scaling on equipment:


First, the scale attached to the heat transfer surface is difficult to remove, which increases the maintenance cost, not only consumes manpower and material resources, but also damages the heating surface and reduces the service life of the heat exchanger.


Second, after the scale is produced, it will reduce the circulation cross-section inside and outside the heat transfer surface and increase the circulation resistance of circulating water inside and outside the heat transfer surface. In severe cases, the circulation cross-section is very small or even completely blocked, which will make the heat exchanger unable to operate normally.


Third, the scale has a poor thermal conductivity, which is 30 ~ 50 times smaller than that of steel. The presence of scale will make the heat transfer on the heating surface worse, so that the heat transfer surface cannot reach the ideal temperature drop. According to the relevant information, after the experiment, the efficiency of heat exchanger will be reduced by about 10% when the scale with thickness of 1mm is produced.


Treatment method of heat exchanger scaling:


1. Softening by dosing. Softening treatment with chemicals has the characteristics of simple method, high efficiency, good economy and no need for special water-making equipment. It is a practical anti-scaling water treatment method. According to the different dosing methods, there are two types: calibrator treatment and anti-scaling treatment.


2. Ion bar anti-scaling water treatment. Ion bar anti-scaling water treatment is a new and advanced water treatment equipment. The application in hot water circulation system, central air conditioning system and circulating cooling water system has achieved satisfactory anti-scaling effect, and it is a promising new water treatment equipment, especially in heat exchanger, and the effect will be more remarkable.


3. Magnetization anti-scaling treatment. The principle of magnetization anti-scaling treatment is to utilize the polarity of water molecules, that is, water molecules are covalently combined. When the water flow passes through a high-intensity magnetic field, under the action of the multimolecular association in the water and the ionic magnetic field, the original association composed of single scattered multi-ions is broken up into single or short-bonded associations, which vertically cut the magnetic field lines of the external magnetic field at a certain speed to generate induced current. Therefore, when each ion establishes a new magnetic field in the same direction as the external magnetic field, the adjacent polar ion molecules will compress and attract each other in an orderly manner, which will lead to the change of crystallization conditions. The formed crystals are very loose, poor in compressive and tensile strength, and fragile, and their adhesive force and adhesion are weak, so they are not easy to adhere to the heated surface to form scale.