In flue gas ducts with high dust concentrations or hot air circulation systems, ash accumulation on heat exchanger fins gradually weakens heat transfer capability, and O&M personnel often need to balance cleaning methods, maintenance cycles, and equipment service life. The HXL-680 tube-fin heat exchanger provides a customizable ash accumulation control solution for such operating conditions.
Mechanical rapping cleaning is relatively suitable for dry dust conditions, but long-term use may cause fatigue at the fin root, especially at the welded joint between the fin and the base tube. Online compressed air blowing has little impact on the production process and can be used as a routine maintenance measure; it is recommended to set the blowing cycle based on the on-site dust characteristics. For high-temperature dust-laden conditions, the fin pitch can be designed at 8~12 mm to reduce ash bridging; the base tube can use heat-resistant alloy steel, with a design task temperature of up to 850°C, meeting the hot air circulation requirements of heater supporting systems.
The design pressure, design temperature, and connection specifications of the HXL-680 tube-fin heat exchanger can be customized according to project requirements and should be clearly marked on the nameplate. The finned tube arrangement, fin pitch, and base tube material can be adjusted according to flue gas composition, dust concentration, and allowable pressure drop. The heat transfer area is determined through verification based on heat load and temperature difference, with no preset fixed value.
When the equipment is positioned, the fins should be protected from extrusion deformation, and the connection direction should be consistent with the pipeline routing. In the initial operation period, it is recommended to check ash accumulation once a week and adjust the blowing frequency according to pressure difference changes. During shutdown maintenance, the inspection door should be opened only after the equipment temperature has dropped to near ambient temperature, to avoid uneven contraction at the connection between the fins and the tube sheet caused by rapid cooling. If a mechanical rapping device is used, the rapping frequency and amplitude need to be checked regularly to prevent fatigue cracking at the fin root.
This type of heat exchanger is suitable for scenarios such as dust-laden flue gas waste heat recovery, hot air circulation heating, and drying systems. During selection, parameters such as flue gas flow rate, inlet and outlet temperatures, dust concentration, and allowable pressure drop need to be provided to determine the fin pitch and cleaning method. For high-dust conditions, priority should be given to online compressed air blowing combined with an adjustable fin pitch design; for dry dust and occasions where frequent shutdowns are not allowed in production, a combined mechanical rapping and blowing scheme can be evaluated.
