Heat exchanger cleaning and scaling prevention measures

      Heat exchanger is a compact and efficient heat exchange equipment. It is an excellent equipment for heating, cooling, heat recovery, rapid sterilization, and other purposes. It is widely used in industrial fields such as chemical plants, power plants and petrochemical enterprises. Due to the long-term operation of heat exchanger, the difference in the purity of cooling or heating side and difference in the nature of process medium itself lead to fouling of heat exchanger is inevitable. These scales that are continuously deposited on the inner surface of heat exchanger not only affect the heat exchange efficiency, but also increase energy consumption. In severe cases, it will cause shutdown due to insufficient cooling water flow and pressure drop. Therefore, to make the heat exchanger play its heat conduction function and ensure the normal production, it needs to be cleaned regularly to remove dirt.

　　For commonly used heat exchangers, according to scaling mechanism, it can be divided into the following categories: crystallization scaling, granular scaling, chemical reaction scaling, corrosion scaling, biological scaling, and coagulation scaling. Therefore, the actual dirt on the heat exchange surface is often a mixture of various dirt. When cleaning heat exchanger, we also need to choose different cleaning methods according to the actual structural conditions.

　　The cleaning of heat exchanger is mainly divided into the tube side and shell side. The shell side is generally cleaned by hand-held high-pressure spray nozzle, or the nozzles are arranged on the device fed by mechanical arm, and the nozzles are aimed at the vertical and horizontal gaps between the tubes. The moving device cleans the dirt between the tubes longitudinally until all the dirt in the gaps between tubes is cleaned, thus completing the cleaning of shell side of heat exchanger. To clean tube side, first remove the head and tail of heat exchanger to expose all the tubes, then use a rigid spray gun or pipeline cleaning nozzle to insert the tube hole at a distance of 200-300mm, open the control valve, and let the high-pressure water flow Then, during the cleaning process, gradually advance the nozzle to the deep part of pipe until high-pressure water jet is ejected from the other end of heat exchanger. Afterwards, operator slowly withdraws the pipeline cleaning nozzle under working condition, and the dirt continues to be broken until spray nozzle is pulled back to the nozzle when it was fed in, and the dirt is also discharged from the pipeline one after another.

　　Thereafter, use the same method to clean the tubes one by one until the tube side of entire heat exchanger is cleaned. Sinpo provides you with a variety of high-pressure cleaners for heat exchangers to meet different cleaning needs.

　　In addition, we should also take some measures to prevent scaling in daily use.

　　1. Strictly control the water quality during operation. Strict water quality testing must be carried out on the water in the system and softened water in a softening tank. Only after passing the test then it be injected into pipe network.

　　2. When new system is put into operation, heat exchanger should be separated from the system, and after a period of circulation, heat exchanger should be incorporated into the system. To prevent impurities in the pipe network from entering the heat exchanger.

　　3. In the whole system, decontamination device and filter should be cleaned irregularly, and pipe network should also be kept clean to prevent heat exchanger from being blocked.