Scale formation and measures in plate heat exchangers

Due to the refrigerant fluid (chilled water) receiving heat from the mission fluid (cooling water), the cooling water of the plate heat exchanger is undergoing heat exchange. By raising its temperature, CO2 is precipitated under the influence of the temperature of CaHCO32 and MgHCO32, which were originally dissolved in water, to form slightly soluble CaCO3 and MgCO3. As the melting degree of CaCO3 and MgCO3 decreases with the increase of temperature, they crystallize and precipitate from the water. When these crystals continuously deposit on the surface of the heat exchanger, they form very hard scale.
The increase in energy consumption and the significant risk of scale formation is to reduce the heat transfer efficiency of the exchanger. In addition, when scale appears on the mission fluid (cooling water) side, it can cause insufficient cooling water flow and a decrease in pressure, and in severe cases, lead to production shutdown.
The efficiency of heat exchange weakens when the thickness of scale reaches 1.6mm, resulting in high heat loss. When the thickness of scale in the condenser tube is 0.3mm. This well-known scale has a significant impact on the thermal conductivity of plate heat exchangers. In order to ensure the abnormal performance of the heat exchanger, regular cleaning and complete cleaning of scale are necessary. Individual use of EPDM gaskets is an important component and function of plate heat exchangers, and the vulnerable component is the sealing gasket of the plate heat exchanger. Acid resistant, alkali resistant, and salt resistant. Reality has confirmed that aMDEA solution with added defoamers will experience swelling of the adhesive pad. Based on the current operating situation, the operating life of the rubber gasket is approximately 12 years. Accurate control has a direct impact on the operating life of the plate heat exchanger. Therefore, during the operation of the heat exchanger, improper operations such as water hammer that may affect its performance should be avoided, and appropriate filters should be added to the medium.
If not in use, for backup equipment. The bolts should be tightened to the specified size to ensure the operating life of the gasket and heat exchanger plate, and then clamped according to the requirements during operation.
When the signal hole detects the medium flowing out, it should be analyzed when the equipment is running continuously. If the bolts are loose or elongated due to heat exchange, caution should be taken when clamping them, as the main reason why plate heat exchangers have a high heat transfer coefficient is that their plate corrugations can cause turbulence in the fluid at lower flow rates. Non employees may cause irreparable damage during clamping. When the plate heat exchanger is in the operating state, it is recommended not to clamp it. If aging of the sealing gasket is found, it should be replaced.