Chemical cleaning method for heat exchanger cleaning

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Chemical cleaning methods for heat exchanger cleaning: These methods involve adding scale removers, acids, enzymes, etc. to the fluid in order to reduce the adhesion of dirt to the heat exchange surface, thereby allowing it to be removed from that surface. The chemical cleaning methods currently in use include: the circulation method: using a pump to force the cleaning solution to circulate for cleaning purposes. Impregnation method: Fill the equipment with the cleaning solution and let it stand for a certain period of time. Surge method: Fill the device with cleaning solution, then periodically remove a portion of the solution from the bottom and pour it back into the device to achieve thorough mixing and cleaning. Before cleaning the equipment, the following preparations should be made: understand and inspect the type, model, geometric shape, and dimensions of the equipment to be cleaned; determine the material of the equipment as well as the areas that need to be cleaned. Based on the actual conditions, decide on the type of cleaning agent, as well as the concentration and amount of cleaning solution required. Arrange for a suitable source of water for cleaning, a heat source for heating the cleaning solution, and measures for handling and disposing of wastewater. Conduct a survey of the dirt present on the equipment. Compared to mechanical cleaning, the advantages of chemical cleaning are as follows: it is not necessary to disassemble the equipment, allowing cleaning to be carried out in areas that cannot be reached by mechanical cleaning. Chemical cleaning ensures uniform cleaning; even the smallest gaps can be cleaned, without any residual particles that could serve as a basis for new deposits of dirt. It also helps to prevent damage to the metal surface, as sharp edges resulting from mechanical cleaning can promote corrosion and lead to the formation of dirt in those areas. Rust prevention and passivation treatments can be applied after cleaning to prevent rusting. Chemical cleaning can be carried out on-site, with less physical effort required compared to mechanical cleaning. To save labor and costs associated with shutdown cleaning, extend operation cycles, and reduce maintenance expenses, various online mechanical and chemical cleaning systems have been developed. Online chemical cleaning has been developed over the past few decades based on conventional chemical cleaning; its main difference from conventional chemical cleaning is that the equipment does not need to stop operating. Initially, this method was only applicable to the removal of fouling on the cooling water side in condensers and coolers; it is now also successfully used in heat exchangers for hydrocarbon processing.