Application And Maintenance Of High And Low Temperature Dry Coolers in Gas Systems

In actual operation, the differences in high and low temperature conditions lead to a significant differentiation in the types of faults faced by dry coolers, but the core problems are concentrated in three categories: heat transfer efficiency attenuation, system leakage corrosion, and auxiliary component failures. Under high temperature conditions, heavy hydrocarbons, tar, and other organic compounds in gas are prone to cracking at high temperatures, forming stubborn oil deposits on the inner walls of heat exchange tubes. At the same time, dust and oil stains accumulate on the surface of fins, resulting in a significant increase in thermal resistance and a decrease of more than 30% in heat transfer efficiency. When the temperature difference between gas inlet and outlet exceeds 7 ℃ or the outlet temperature cannot meet the design requirements, it indicates that the heat transfer efficiency has seriously declined; In addition, high temperature environments can accelerate the electrochemical corrosion of corrosive media, and stress concentration areas such as welded joints and tube plate edges are prone to pitting and intergranular corrosion, ultimately leading to perforation and leakage of the tube body. Under low temperature conditions, water vapor in gas condenses and combines with impurities to form wet scale, which adheres to the pipe wall and hinders heat transfer. When the environmental humidity is high, the surface of the fins is prone to frost and ice, completely blocking heat transfer on the air side; At the same time, the acidic components in condensed water and gas form an acidic solution, causing corrosion under the scale. Low temperatures in winter can also increase the brittleness of metal materials, and the thermal stress generated by frequent starting and stopping can easily cause weld cracking. In terms of auxiliary systems, high temperature conditions can easily lead to overload and burnout of fan motors, aging of variable frequency controller components, while low temperature conditions may cause excessive vibration due to blade frosting and imbalance, or failure of anti freezing protection devices can cause pipe bundle freezing and cracking. These faults will directly affect the normal operation of the dry cooler.

In addition, standardized operation is an important prerequisite for reducing faults. Avoid frequent starting and stopping of equipment under high temperature conditions. Preheat for 30 minutes before starting and keep the fan running for 15 minutes after stopping to prevent residual gas in the pipe from decomposing at high temperatures; Strictly control the cooling rate under low temperature conditions, not exceeding 10 ℃ per hour, to avoid component damage caused by thermal stress. At the same time, establish a complete equipment file to record the types of faults, handling plans, replacement parts, and other information for each maintenance, optimize maintenance cycles based on operational data, and shorten maintenance intervals appropriately during high load operation. Through scientific working condition adaptation, precise fault diagnosis, and standardized maintenance, high and low temperature dry coolers can continuously play a stable heat exchange role in gas systems, effectively reducing downtime caused by faults, extending equipment service life, and providing solid guarantees for the safe and efficient operation of gas treatment systems.