Causes and hazards of scaling in plate heat exchangers

  During the use of the plate heat exchanger, due to improper operation of the water treatment equipment, the water quality control is not strict, and Causes and hazards of scaling in plate heat exchangersthe circulating water that does not meet the water quality standard is injected into the heat exchanger.Calcium and magnesium carbonate in water decomposes into calcium carbonate and magnesium hydroxide precipitates upon exposure to heat.Some of these deposits are bonded to the heated surface of the heat exchanger to form a hard scale.The other part is suspended in circulating water and deposited on the heated surface with a lower flow rate to form secondary scale.Since the thermal conductivity of scale is extremely poor (the thermal conductivity is only 1130-1150 of the thermal conductivity of the steel), the heat transfer of the plate heat exchanger is deteriorated.The heat transfer efficiency is greatly reduced, resulting in a serious waste of heat energy, thereby affecting the heating effect and causing serious negative effects on the heating unit.According to the data, the thermal efficiency is reduced by about 8% for every 1 mm of scale increase. The presence of scale can block the plate heat exchanger passage, increasing the resistance of the system, affecting the safety of the equipment and the normal operation of the thermal system.