Heat transfer and corrosion resistance of thin-walled coil-welded titanium tubes for seawater desalination

With the continuous development of the seawater desalination industry, the evaporation heat transfer tube, which is one of the core components of thermal desalination devices, has also attracted the attention of scientific researchers and technicians. Traditional stainless steel, copper alloy, aluminum alloy, and other materials cannot fully meet the requirements of seawater application environment for material corrosion resistance, mechanical properties, and lightweight, while industrial pure titanium TA2 has excellent corrosion resistance, good plastic toughness and high It is an ideal material for making heat exchange elements of thermal seawater desalination devices. At present, in the large-scale thermal seawater desalination plants constructed in my country, rolled seamless titanium tubes have been applied to a certain extent, but the large-scale promotion of titanium heat transfer tubes is still greatly limited. The high price of seamed titanium pipes leads to high material investment costs.

Many scholars at home and abroad have been committed to the design and development of thin-walled Grade 2 Pure Titanium Tube and the research on corrosion resistance. The application history in the field of horizontal tube falling film seawater desalination technology is short, and the experimental data on the heat transfer coefficient and corrosion resistance of titanium tube falling film evaporators are insufficient, so it is difficult to guide the design of seawater desalination system. In addition, the wall thickness of titanium welded pipes used in seawater desalination projects is currently 0.5mm, which is difficult to meet the control requirements of seawater desalination projects on material costs. , reduce the amount of titanium used in equipment. Based on this, TA2 industrial pure titanium ϕ22mm×0.4mm thin-walled coiled titanium tube was prepared by tungsten argon arc welding (TIG) process, and the application experiment of low-temperature multi-effect distillation seawater desalination was carried out to test its corrosion resistance. performance and heat transfer performance, verify the quality of welded joints, obtain experimental data, and provide technical support for the large-scale production of 0.4mm thin-walled coiled titanium tubes and their popularization and application in seawater desalination projects.