TIG-Welded Coiled Tube Heat Exchanger for Carbon Capture

--An Analysis of Core Technologies in TIG-Welded Coiled Tube Heat Exchangers for Carbon Capture Systems

Explore the technical advantages of TIG-welded coiled tube heat exchangers in carbon capture systems. Featuring high-strength continuous structures and superior heat transfer efficiency, these corrosion-resistant coils ensure safe, long-lasting operation in high-pressure CCUS applications.

Carbon capture, utilization, and storage (CCUS) technology is a decisive measure for achieving decarbonization in heavy industry. In the carbon capture process, the compression, cooling, and liquefaction stages of carbon dioxide place extremely high performance demands on heat exchange equipment. TIG-welded coiled tube heat exchangers, with their continuous structure and high strength, are gradually becoming the preferred heat transfer components for high-pressure carbon capture systems.

TIG welding, or tungsten inert gas welding, enables deep fusion of the tubing and high-purity connections. Material engineering test data indicates that coiled tubes formed using automated TIG welding processes can achieve mechanical strength in the weld zone that consistently reaches over 95% of the base material’s strength. When handling supercritical carbon dioxide, system operating pressures typically range from 20 to 40 MPa. The high-strength, continuous, seamless design completely eliminates the risk of flange seal leakage—a common issue in traditional segmented straight-tube heat exchangers—ensuring the safe operation of high-pressure fluids.

The helical fluid dynamics of the coils significantly enhance the system’s heat transfer efficiency. As fluid flows through the curved tube walls, centrifugal forces are generated, inducing secondary flow effects that effectively disrupt the thermal boundary layer on the tube walls. Thermodynamic engineering data shows that, under equivalent volume and operating conditions, the overall heat transfer coefficient of helical coil heat exchangers is 30% to 40% higher than that of traditional shell-and-tube heat exchangers. This highly compact design significantly reduces the equipment’s footprint, meeting the stringent space constraints of offshore platforms or high-density chemical plants.

Carbon capture operations are often accompanied by high-concentration, wet, acidic corrosive media. The material properties of the tubing directly determine the system’s safety. Strictly adhering to ASME and ASTM manufacturing standards, TIG-welded coils made from high-purity austenitic duplex steel or corrosion-resistant nickel-based alloys effectively limit the annual corrosion rate to less than 0.01 millimeters. Combined with 100% eddy current testing and high-pressure testing during manufacturing, these high-performance coils ensure absolute gas tightness throughout the carbon capture process and extend the heat exchanger’s service life to over 20 years.