Application of titanium rod in chlor-alkali industry

- Jul 25, 2018 -

Application of titanium rod in chlor-alkali industry

Chlor-alkali industry is China's raw material industry, its products are basic chemical raw materials, widely used in textile, paper, pesticide, medicine, building materials, metallurgy and other industries. Chlor-alkali is one of the key development projects in the chemical industry, and it is also a large-scale domestic use of titanium. The chlor-alkali industry is a highly corrosive industry. The process media and products in the production process, such as saturated brine, wet chlorine, caustic soda, hydrochloric acid and sulfuric acid, are extremely corrosive. Therefore, it must be carefully selected in the chlor-alkali production project. The structural materials of the device, otherwise there will be run, run, drip, leak and other phenomena in the production, which seriously affect the normal production and product quality. In recent years, with the rapid development of China's chlor-alkali industry and the emergence of new equipment and new processes, the application range of titanium in the chlor-alkali industry has gradually expanded, widely used in the manufacture of metal anode electrolyzers, ion-exchange membrane electrolyzers, and wet oxygen. Cooler, refined brine preheater, dechlorination tower, chlorine gas scrubber, etc. The parts of these equipment used to be non-metallic materials. Due to the unsatisfactory mechanical properties, thermal stability and processing properties of non-metallic materials, the equipment is cumbersome, energy-consuming, short-lived, and poor in quality.

Titanium rods have excellent corrosion resistance and mechanical properties and are widely used in many sectors. Especially in chemical applications, titanium can be used as a corrosion-resistant material instead of stainless steel, which is of great significance in extending the life of the equipment, reducing costs, preventing pollution and increasing productivity. In recent years, the range of titanium used in chemical industry in China has been expanding, and the amount of titanium has increased year by year. Titanium has become one of the main anti-corrosion materials in chemical equipment. As a corrosion-resistant structural material used in chemical plants, titanium has become an ideal material in chemical equipment.

The chlor-alkali industry is an important basic raw material industry, and its production and development have a great impact on the national economy. This is because the corrosion resistance of titanium to chloride ions is superior to that of commonly used stainless steels and other non-ferrous metals. At present, titanium is widely used in the chlor-alkali industry to manufacture metal anode titanium electrolysis cells, ion membrane electrolyzers, wet chlorine coolers, refined brine preheaters, dechlorination towers, chlorine gas cooling scrubbers, and the like. In the past, the main components of these equipments used non-metallic materials (such as graphite, polyvinyl chloride, etc.). Due to the poor mechanical properties, thermal stability and processing performance of non-metallic materials, the equipment was cumbersome, energy-intensive and short-lived. And affect product quality and pollute the environment. Therefore, since the 1970s, China has successively replaced the graphite electric trough with metal anode electric tank and ion membrane electric trough, and replaced the graphite cooler with titanium wet chlorine cooler, and achieved good results.

For example: the application of titanium wet chlorine cooler. Salt electrolysis production of caustic soda is to produce a large amount of high temperature wet chlorine gas, the temperature is generally 75 ~ 95 ° C, need to be cooled and dried before use. The production of chlorine gas from salt electrolysis in China has previously affected the production and quality of chlorine gas due to unreasonable cooling process or corrosion problems of cooling equipment, and it has also seriously polluted the environment. The titanium cooler, which is resistant to high temperature wet chlorine gas, is put into production, which changes the production appearance of chlorine in the chlor-alkali industry. Titanium is extremely resistant to corrosion in high temperature wet chlorine atmosphere. The corrosion rate of titanium in chlorinated water at normal temperature is 0.000565mm/a; in chlorine water at 80 °C, the corrosion rate of titanium is 0.00431mm/a; in 95% In wet chlorine gas, the corrosion rate of titanium at room temperature is 0.00096 mm/a. Many chlor-alkali applications often use titanium wet chlorine gas coolers, some of which have been in use for almost 20 years and are still intact.