While producing caustic soda by electrolytic salt, a great deal of hot wet chlorine gas is produced, which can not be used until cooled and dried. There are two methods for cooling hot and humid chlorine: direct water spray and indirect cooling by tube cooler.
Direct cooling not only produces a large amount of chlorine-containing water but also pollutes the environment seriously. Moreover, the loss of chlorine gas is large, the consumption of sulfuric acid is high and the working conditions in the workshop are poor. An indirect cooler is made of graphite cooler, glass tube cooler, ceramic cooler, plastic cooler, etc. However, there are many problems such as poor corrosion resistance, easy cracking, and easy aging, while stainless steel indirect cooler can only be used for 8-10 days and requires shutdown repair. The test results show that titanium is extremely resistant to corrosion under high temperatures and humid chlorine with an annual corrosion volume of 0.0025mm. The use of titanium coolers in the production of the Chlor-alkali industry can shorten the process of cooling and drying, reduce the loss of chlorine, reduce environmental pollution and create conditions for the stable operation of compressed gas and high drying.
Titanium chlorine cooler has been used since 1963 in Russia. Its heat exchange area is 140 M. Titanium pipes with diameters of 300-600 mm and lengths of more than 500 m are also used to transport humid chlorine. The wet chlorine coolers used in the Chlor-alkali industry in Russia are almost titanium. Allied Chemical Company, USA, uses titanium instead of graphite to make it cooler in the production of the Chlor-alkali industry. The original graphite tube is scrapped for 2-3 years. A 78m titanium cooler is used to complete the cooling capacity, while the graphite cooler needs 140 M.
The first titanium cooler in China was manufactured in 1965 by the Jinxi Chemical Machinery Plant with a small heat transfer area of 16.8m. Since 1973, titanium tube coolers have been used successively in Chlor-alkali plants in Shanghai, Tianjin, Beijing, Liaoning, and Guangdong provinces and cities with good results. There are hundreds of titanium tube coolers in China.
