Under normal circumstances, the plate to plate heat exchanger should be cleaned according to the scaling situation.It must be cleaned when the heat transfer effect cannot meet the process design requirements,. From the point of view of energy saving and consumption reduction, if the heat transfer surface of the plate heat exchanger is attached with 0.2 to 2 mm of scale, the heat transfer efficiency will be reduced by 10 to 40%, and the 0.3 mm scale will reduce the heat transfer efficiency of the heat exchanger by 90%.Then How to clean plate to plate heat exchanger?
(1)Chemical cleaning method
In this method, a chemical solution is circulated through the heat exchanger to dissolve and discharge the dirt on the surface of the sheet. This method does not require disassembling the heat exchanger, which simplifies the cleaning process and reduces the labor level of cleaning. Since the corrugation of the plate can promote the turbulent flow of the cleaning liquid and facilitate the dissolution of the scale layer, the chemical cleaning method is an ideal method.
(2)Mechanical (physical) cleaning method
In this method, the plate is manually washed with a brush to achieve the purpose of removing dirt on the surface of the plate. Although this method is relatively straightforward, it is not easy to clean the harder and thicker scale layer.
(3) Comprehensive cleaning method
In the case where the dirt layer is relatively hard and thick, it is difficult to clean by simply using one of the above methods. The comprehensive method is to first soften the scale layer by chemical cleaning, and then remove the scale layer by mechanical (physical) cleaning method to keep the plate clean.