Air separation units are the core "power heart" of the coal chemical and salt chemical industries, and the interstage heat exchangers of the supporting centrifugal compressors directly determine the energy consumption, operational stability, and service life of the entire unit. As a leading enterprise in China's industrial heat exchanger sector, Defon Heat Exchanger has been deeply engaged in the industry for over 30 years, continuously providing localized high‑efficiency heat exchange solutions for large‑scale air separation and chemical compression applications.
Defon's connection to the air‑separation compressor industry can be traced back to its early efforts in overcoming "bottleneck" technologies such as charge‑air coolers for marine diesel engines. As that technology matured and achieved localization, Defon redirected its R&D momentum toward air‑separation compressor heat exchangers, leveraging its continuous breakthroughs in enhanced heat transfer to gradually break the long‑standing market monopoly of foreign brands.
Building on more than 30 years of research and experience in enhanced heat transfer, Defon has independently developed a surface‑contact low‑thermal‑resistance technology for its new‑generation heat exchanger assemblies. The Defon centrifugal compressor heat exchanger series is centered on two independently developed core products: housed fin‑tube heat exchangers and built‑in fin‑tube heat exchangers. The former combines the pressure‑bearing reliability of traditional shell‑and‑tube heat exchangers with the compactness and efficiency of fin‑tube designs; the latter adopts a standardized modular design that can be directly integrated into the compressor casing, enabling skid‑mounted integration with the compressor unit.
Fin‑Tube Heat Exchangers:
A Technological Breakthrough in Efficiency, Compactness, and Low Resistance
Defon's fin‑tube heat exchangers deliver outstanding technical performance:
Compared with traditional shell‑and‑tube heat exchangers, they offer a heat transfer efficiency improvement of over 30%, with a more compact structure that significantly saves installation space. Through optimized flow‑field and structural design, pressure drop can be as low as 3 kPa, effectively reducing flow loss and lowering unit energy consumption.
In terms of reliability and durability, Defon's fin‑tube heat exchangers also excel: thermal compensation design prevents cracking risks caused by temperature differentials; reliable sealing structures and high‑quality materials ensure impact resistance and leakage protection; and the integrated explosion‑proof and vibration‑damping design, combined with reinforced tube‑bundle supports, gives the product excellent seismic and fatigue resistance.
Customized heat exchanger core bundles and anti‑corrosion coatings can extend equipment service life and ensure long‑term stable system operation.
In addition, the integrated gas‑liquid separation unit design eliminates the need for additional separation equipment, further simplifying system layout.
Wide Range of Applications:
Pressure range: 0‑8 MPa; temperature below 200°C;
Oxygen production capacity: 1,000 to 125,000 Nm³/h;
Tube‑side/shell‑side media: water and (air, CO₂, nitrogen, gas mixtures, etc.);
Heat exchanger tube materials include: BFe10‑1‑1, BFe30‑1‑1, T2, S30403/S31603, S22053, etc.; tube diameters: 10mm‑25mm;
Fins: available in coated or uncoated aluminum fins/steel fins;
Fully meeting the corrosion‑resistance and heat‑exchange requirements of various operating conditions.
Defon's fin‑tube heat exchangers have been validated in multiple major national projects, including the supply of 2 heat exchangers for the Hualu Hengsheng (Jingzhou) 100,000 Nm³/h air separation project and 7 heat exchangers for the Yingcheng Xindu 85,000 Nm³/h air separation project. These projects, which meet the high safety requirements of continuous chemical production, fully demonstrate the reliability and efficiency of Defon's products.
Beyond Air Separation
Defon's heat exchanger product line covers a wide range of heat‑exchange equipment across multiple industries and operating conditions. In addition to air‑separation/centrifugal compressor heat exchange equipment, the company also provides customized heat exchange solutions for new energy, metallurgy, electric power engineering, marine, and other fields.
Technological innovation has always been the core driving force behind Defon's sustained growth. We remain committed to independent R&D and continue to deepen our work in the underlying technologies of enhanced heat transfer. Leveraging our thermal simulation‑based digital R&D platform, we continuously tackle and break through various challenging operating conditions — including high temperature, high pressure, strong corrosion, and ultra‑long‑cycle operation — iteratively launching localized heat‑exchange equipment with comprehensive upgrades in energy efficiency, stability, and compactness. Going forward, we will continue to iterate and strengthen our core enhanced heat‑transfer technologies, delivering reliable, localized, green, and efficient heat‑exchange equipment to power the low‑carbon transformation of various industries.
