In chemical production, chemical equipment corrosion is a major problem. A huge amount of steel (1797, 10.00, 0.56%) is wasted every year due to corrosion. In my country, the main cause of equipment damage in the chemical industry is also due to corrosion. Therefore, the service life of many equipment is only 1-2 years, and the shortest is only 1-2 months. Titanium has excellent properties in terms of corrosion resistance, wear resistance and erosion resistance. Although titanium equipment has a high one-time investment, its service life is several times, dozens of times that of carbon steel, stainless steel and cast iron equipment. Due to its outstanding advantages such as low density, high strength and good corrosion resistance, titanium material has successfully solved the serious corrosion problem of equipment in chemical production and has been favored, bringing a leap to the chemical industry anticorrosion technology.
The chemical system is the first and largest industrial sector using titanium in China's civil industry. In the past 10 years, the amount of titanium used in my country's chemical industry is equivalent to the sum of the titanium production in 2009 and 2010.
Application of titanium in chemical industry
At present, the main application fields of titanium in the chemical industry are:
1. Chlor-alkali industry
The earliest and largest user of titanium in chemical industry is the chlor-alkali industry. These include the production of chlorine gas, oxychloride, pesticides, drifting powders, etc. In the production of chlorine, titanium equipment and pipes account for almost a quarter of its total mass'. Such as metal anode electrolyzers, ion membrane electrolyzers and anolyte pumps, tubular wet chlorine coolers, chlorine wastewater dechlorination towers, chlorine cooling scrubbers, refined brine preheaters, pumps and valves for vacuum dechlorination, etc. .
2. Soda ash industry
In the production of soda ash, titanium materials are mainly used in the crystallization external cooler, the ammonia condenser at the top of the distillation column, the ammonium chloride mother liquor heater, the plate heat exchanger, the umbrella plate heat exchanger, the cooling pipe of the carbonization tower, and the carbon dioxide turbine compressor. Rotor impeller, lye pump, etc.
3. Vacuum salt industry
Titanium ammonia evaporator, titanium preheater, titanium precooler, titanium flange, titanium tube sheet, titanium pump casing and titanium elbow.
4. Petrochemical fiber
At present, petrochemical fiber enterprises such as polyester, nylon and vinylon, which are imported from abroad or domestically designed and manufactured by themselves, have used some titanium equipment. The application of titanium equipment has played a positive role in the development of chemical fiber production in my country, especially for safe, stable and continuous production, to improve product quality, to prevent premature corrosion and failure of stainless steel, to improve equipment service life, to reduce downtime and maintenance, and to improve comprehensive economic benefits. made a significant contribution.
5. Fine chemical industry
The industrial raw material of propylene oxide plant is a strong corrosive medium. The two main raw materials used in PO production are liquid chlorine and propylene. These strong corrosive media lay the foundation for corrosion of PO production equipment and pipelines. Production under this process conditions, such as carbon steel, Al, Cu, Ni, stainless steel, etc. No metal can resist corrosion, only titanium is an ideal corrosion-resistant metal material.
6. Inorganic salt industry
Inorganic salts mainly include chlorate and potassium salts. Domestic sodium chlorate production has developed rapidly in the past two years, with a total production capacity exceeding 1 million tons, and another about 500,000 tons in expansion or preliminary work. Titanium chlorate equipment mainly includes electrolytic cells, titanium anodes, reaction generators, evaporators, etc. About 15t of titanium materials are required for every 10,000 t of sodium chlorate.
Potash products include potassium chloride, potassium sulfate, potassium nitrate, potassium carbonate, etc. At present, the total production capacity of potassium nitrate and potassium carbonate in China is about 600,000 tons. Evaporators, preheat tanks and coolers in the production of potassium nitrate and potassium carbonate require titanium equipment.
7. Other industries
Titanium dioxide Titanium is used in thin film concentrators, calcining kiln feed pipes, centrifuge distribution plates, etc.
Urea Titanium material is used for lining of urea synthesis tower, ammonia stripper, heater of general decomposition tower, inlet of methylamine pump, liquid discharge valve and spring, high pressure mixer, etc.
Dyestuff Titanium is used in coil heat exchangers, absorption towers, purification tower nozzles, fans, water ring vacuum pumps, filters, etc.
Titanium nitrate is used in nitric acid evaporators, nitrogen oxide tail gas preheaters, nitric acid vapor preheaters, gas scrubbers, rapid coolers, condensers, turbo blowers, pumps, valves, pipes, etc.
