Friends who use plate heat exchange units should know that the plate heat exchange units are prone to fouling for a long time. At this time, descaling is needed. So, which methods are better for cleaning the plate heat exchanger?

1. Pickling temperature: Increasing the pickling temperature is beneficial to improve the descaling effect. If the temperature is too high, it will aggravate the corrosion of the plate heat exchange unit plate by the pickling solution. Through repeated experiments, it is found that the pickling temperature is preferably controlled at 60 ° C.
2. Pickling solution concentration: According to repeated tests, the pickling solution should be prepared at a concentration of 81.0% formic acid, 17.0% water, 1.2% buffer, and 0.8% surfactant, with excellent cleaning effect.
3. Pickling method and time: The pickling method should be performed by a combination of static immersion and dynamic cycling. The pickling time is static soaking for 2h, and then dynamic cycling for 3 ~ 4h. During the pickling process, the acid pickling concentration should be sampled frequently. When the difference between the two adjacent test concentrations is less than 0.2%, the pickling reaction can be considered End.
4. Passivation treatment: After pickling, most of the scale and metal oxides on the surface of the plate heat exchange unit are dissolved and peeled off, exposing brand new metal, which is easy to corrode. Therefore, after pickling, the plate heat exchange unit plate The sheet is passivated.
In order to better protect the plates of the plate heat exchange unit when cleaning the plate heat exchange unit, we hope that everyone will operate in accordance with the above requirements when cleaning. Take appropriate protective measures after cleaning to extend the life of the plate heat exchanger unit.