The plate heat exchanger has the characteristics of light weight, small floor space, low investment, high heat exchange efficiency, flexible assembly, easy to remove scale, and its role in heating work.Due to the small flow cross section of the plate heat exchanger, clogging is likely to occur after scaling. The heat exchange efficiency of the plate heat exchanger is reduced, which affects the safety of the equipment and the normal heat consumption of the user. Therefore, the cleaning of the plate heat exchanger can not be ignored.Procedure for cleaning the scale of the plate heat exchanger:
(1) Punching: Before the plate heat exchanger is pickled, the heat exchanger is firstly flushed so that there are no impurities such as mud and scale inside the heat exchanger, which can improve the pickling effect and reduce the acid consumption of pickling.
(2) Pour the cleaning solution into the cleaning equipment and then inject it into the heat exchanger.
(3) Pickling: The plate heat exchanger filled with the acid solution is statically immersed for 2 hours, continuously and dynamically cycled for 3-4 hours, and the positive and negative alternate cleaning is performed every half hour.After the acid washing is finished, if the pH of the acid solution is greater than 2, the acid solution can be reused. Otherwise, the acid washing solution should be diluted and neutralized and drained.
(4) Alkali washing: After the acid washing is finished, NaOH, Na3P04, and demineralized water are prepared in a certain ratio.The heat exchanger is alkali-washed by means of dynamic circulation to achieve acid-base neutralization, so that the heat exchanger plates no longer corrode.
(5) Washing: After the alkali washing is finished, the heat exchanger is repeatedly washed with clean softened water for half an hour.Rinse the residue in the plate heat exchanger thoroughly.
(6) Recording: During the cleaning process, the time of each step should be strictly recorded to check the cleaning effect.
After the end of the cleaning plate heat exchanger, the heat exchanger should be subjected to a pressure test, and it can be used only after passing the test..