Strategies for addressing corrosion issues in heat exchangers of petroleum refining and chemical processing equipment

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Heat exchangers in petroleum refining and chemical processing equipment suffer from severe corrosion during operation. To ensure their proper functioning, it is necessary to apply anti-corrosion coatings to improve the sealing properties of these heat exchangers, optimize sealing solutions to maintain the integrity of the equipment, enhance the resistance to corrosion through sacrificial anode protection, and use protective linings to address corrosion issues in heat exchangers. 1. Applying anti-corrosion coating: Applying an anti-corrosion coating to heat exchange equipment is a form of isolation measure; it separates the surface of the heat exchanger from the external environment, allowing the coating to form a protective barrier on that surface. This prevents damage to the heat exchanger caused by the external environment, while also enhancing its anti-corrosion properties. Currently, there are mainly two types of anti-corrosion coatings used on heat exchangers in petroleum refining and chemical manufacturing processes: one is inorganic anti-corrosion coatings, and the other is metallic anti-corrosion coatings. When treating the surface of heat exchangers with inorganic anti-corrosion coatings, the spraying method is required. Throughout the entire spraying process, the workers strictly follow each step of the procedure. After the spraying is completed, high-temperature baking is applied to improve the quality of the anti-corrosion coating. When treating the surface of heat exchangers with metal anti-corrosion coatings, electroplating is required to apply the coating. Since the electroplating flame can have a negative impact on the heat exchanger during the spraying process, causing it to deform, construction workers must strictly follow the relevant standards when applying metal paint to the heat exchanger in order to achieve good spraying results and effectively reduce the effects of the electroplating flame on the heat exchanger. 2. To optimize the sealing scheme and improve the sealing performance of the heat exchanger, it is necessary to select the appropriate sealing materials for the heat exchanger. There are mainly two types of sealing materials for heat exchangers: one is metal wound gaskets, and the other is corrugated composite gaskets. The stiffness and strength of these two types of gaskets are superior to those of asbestos gaskets; they can effectively reduce the deformation rate of the gaskets and improve the sealing performance of heat exchangers. 3. Sacrificial anode protection: Electrochemical corrosion is a phenomenon that occurs during the operation of heat exchangers; to avoid this phenomenon, sacrificial anode protection must be employed. When electrochemical corrosion occurs in a heat exchanger, an electric current is generated between its anode and cathode, thereby causing certain corrosion to the metal components of the heat exchanger. The corrosion current generated by the metal at a lower potential is used as the cathodic protection current for the body being corroded at a higher potential, thereby achieving the purpose of sacrificial anode cathodic protection. 4. Corrosion inhibitor addition method: The buffer addition method involves adding a buffer to the electrolyte solution, thereby enabling this solution to act as a barrier between the cathode and the anode, and thus reducing the corrosion rate of the heat exchanger. 5. Application of protective linings: When selecting materials for oil refining and chemical processing operations, professionals in this field need to choose appropriate production materials carefully. They must conduct a comprehensive analysis of the operating conditions of heat exchangers, taking into account factors such as pressure, temperature, and the type of medium used, in order to select materials that are suitable for such industrial processes. Typically, materials used in the oil refining and chemical industries include stainless steel, polytetrafluoroethylene, and fiberglass-reinforced plastic. Metal materials have relatively high prices in the market; they possess the ability to withstand harsh operating conditions, and oil refining construction is relatively complex ； Non-metallic materials are relatively inexpensive in the market and lack the ability to withstand harsh environments.