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As is well known, fluoroplastic heat exchangers, thanks to their toughness and the properties of their hoses, **reduce the negative effects caused by vibrations. On the contrary, appropriate vibrations help to remove dirt from these heat exchangers, which facilitates their long-term use and reduces the need for maintenance over time; thus, they offer significant advantages over metal heat exchangers. However, even minor scaling requires regular maintenance of the equipment. Due to the different working media and operating conditions of fluoroplastic heat exchangers during operation, the types of scaling that occur in these heat exchangers also vary. Below is a brief summary of the basic principles and process requirements for scale removal. I. The importance of descaling fluoroplastic heat exchangers: For ordinary fluoroplastic heat exchangers, such as shell-and-tube or frame-type ones, as well as those used in reaction vessels, dirt does not tend to accumulate easily due to the certain flow rate of the liquid within them, coupled with the unique properties of the fluoroplastic tube bundles. However, in cases where the operation time is particularly long, both the tube side and the shell side will develop mild scaling to varying degrees, resulting in a decrease in heat transfer efficiency. Therefore, cleaning and descaling of heat exchangers is an essential task. II. Basic principles of descaling fluoroplastic heat exchangers 1. Dissolution: Acidic solutions can easily react with contaminants such as calcium, magnesium, and carbonates to form soluble compounds, thereby dissolving the scale. 2. Stripping effect: Acidic solutions can dissolve the oxides on the metal surface, breaking the bonds with scale. Thereby removing the dirt attached to the surface of the fluoroplastic heat exchanger tube bundle and causing it to fall off. 3. Gas generation effect: When the acidic solution reacts with dirt such as calcium, magnesium, and carbonates, a large amount of carbon dioxide is produced. Carbon dioxide gas during the leakage process. It exerts a certain driving force on the insoluble or slowly dissolving scale layers, causing the scale to fall off the heated surfaces of the heat exchanger. 4. Dissolution effect: For scale composed of a mixture of silicates and sulfates, as the oxides of calcium, magnesium, carbonates, and iron dissolve in acidic solutions, the remaining scale becomes loose and can be easily washed away by the flowing acidic solution. III. Process requirements for descaling fluoroplastic heat exchangers 1. Acid cleaning temperature: Raising the acid cleaning temperature helps to improve the descaling effect. However, if the temperature is too high, it will exacerbate the corrosion of the heat exchanger plates by the acid solution. Through repeated tests, it has been found that a temperature range of 60–E is appropriate for acid cleaning. 2. Acid pickling solution concentration: Based on repeated tests, the acid pickling solution should be prepared with 81.0% formic acid, 17.0% water, 1.2% buffer, and 0.8% surfactant, which yields an excellent cleaning effect. 3. Pickling method and time: The pickling method should combine static immersion with dynamic circulation. The pickling time consists of 2 hours of static soaking followed by 3–4 hours of dynamic cycling. During the pickling process, samples should be taken regularly to test the pickling concentration; when the difference between two consecutive measurements is below 0.2%, it can be considered that the pickling reaction has been completed. 4. Passivation treatment: After acid cleaning, most of the scale and metal oxides on the surface of the plate heat exchanger are dissolved and removed, exposing the fresh metal surface. This exposed metal is highly susceptible to corrosion; therefore, passivation treatment is applied to the heat exchanger plates after acid cleaning. This article focuses on the removal of scale; generally, cleaning is a very important aspect of the subsequent maintenance of fluoroplastic heat exchanger equipment.