Thread Content
Application of Titanium Nanopolymer Coatings in the Corrosion Protection of Petrochemical Equipment – Wang Wei (Daqing Petrochemical Company, CNPC, Daqing, Heilongjiang 163711) 1. Introduction According to available domestic and international data, corrosion losses account for around 4% of the total national GDP, which is a considerable amount. Moreover, over 80% of the annual costs associated with overhauls, upgrades, and repairs in the petrochemical industry are spent on equipment, pipelines, and metal (non-metal) structures that become unusable due to corrosion; the losses caused by corrosion are quite substantial. To address equipment corrosion that occurs during petrochemical production, especially in environments with harsh corrosion conditions, conventional special anti-corrosion materials are not effective enough to solve the problem. However, in recent years, the highly corrosion-resistant anti-corrosion coating \"Titanium Nanopolymer Coating\" (abbreviated as Titanium Nano Coating) has been used as a protective coating. It addressed the internal corrosion of exhaust fan equipment in acid water tanks, hydrocarbon tanks, oil storage tanks, spherical tanks, and heating furnaces, thereby extending the service life of these devices. 2. Application effects of titanium nano-coating: (1) On acidic water tanks: It resolved the stress corrosion problem in these tanks. The solution to this problem is at the leading level in the petrochemical industry. ⑵Heat exchanger tubes: Titanium nanotube bundles have been used in the oil and gas coolers of petroleum refining units, and after more than 10 years of use, they have achieved good results as well as significant economic benefits. It is currently the leading material in China for corrosion and scaling prevention in heat exchanger tube bundle coatings. The following are the observations regarding the use of titanium nanotube bundles: ① Titanium nanotube bundles have good corrosion resistance and excellent resistance to rust and scale. ② It has good thermal conductivity; it possesses both heat absorption and heat conduction capabilities, with a thermal conductivity rate within the range of metals. Titanium nanotube bundles exhibit better heat transfer performance and higher thermal efficiency compared to non-corrosion-resistant bundles and 7910-coated bundles, making them energy-saving heat exchange bundles. ③ Titanium nanotube bundles are easy to maintain and repair, reducing the workload of maintenance workers as well as the costs associated with repairs. ④ It solves the problem of oil and vapor corrosion resistance in epoxy amine-based coatings and similar products. ⑤The application of the anti-corrosion coating to titanium nanotube bundles involves curing at room temperature, which eliminates the need for high-temperature curing in the existing coating processes for such bundles in China and reduces construction costs. ⑶Oil storage tanks: Titanium nanopolymer coatings are used, providing a surface finish that is the best among the anti-corrosion materials currently in use in China. In particular, it solves the problem of high temperatures (75°C) for media such as naphtha and residue tanks, for which conventional anti-corrosion coatings do not provide adequate heat resistance. Longer service life. ⑷Heating furnace air preheater: Corrosion and protection of the heat exchanger tubes in the air preheater. Anti-corrosion coatings placed in the flue gas address the problem associated with conventional special anti-corrosion coatings, which either lack resistance to temperature changes or fail to provide adequate corrosion protection. A new method has been found to prevent corrosion of the heat pipes in the preheater of a furnace flue. ⑸ GGH heat exchange tubes: They solve the corrosion problem of GGH heat exchange tubes in flue gas heat exchangers in thermal power plants; it remains to be seen whether other anti-corrosion materials can address this issue effectively. ⑹Unit induced draft fan casing: solves the problems of heat pipe flue gas and dew point corrosion caused by flue gas. It effectively demonstrates that this coating is not only corrosion-resistant but can also be used in high-temperature environments. ⑺On hydrogen and hydrocarbon storage tanks for pressure vessels: it effectively addresses corrosion in oil and gas containing various substances such as H2S and HCl, at temperatures around 60°C and under certain pressures. A new method has been found for the corrosion prevention of light hydrocarbon tanks. Solved the problem of low-temperature, wet hydrogen sulfide pressure corrosion cracking in the weld seams and heat-affected zones on the inner walls of natural gas and gas sphere tanks. ⑻Buried sewage pipes: address the issues of corrosion and protection on the inner walls of the pipes, offering strong resistance to penetration and high corrosion resistance ； It has good anti-scaling properties, good temperature resistance, good water resistance, good wear resistance, and good cavitation resistance. Therefore, the use of titanium nanopolymer coatings on petrochemical equipment can effectively solve the problem of equipment corrosion. It can be used as a drag-reducing coating for large pipelines. Several years of application have shown that this coating can play a greater role in preventing corrosion in oil refining equipment. 3. Characteristics of titanium nanopolymer coatings: The use of titanium nanocoatings on petrochemical equipment has addressed the issue of corrosion on the inner walls of such equipment. Its main component, the titanium nano-coating, involves ultra-fining titanium to the nanoscale, thereby **increasing its surface activity. At the same time, the double bonds in the organic compounds are broken to form free bonds, and these combine with each other through chemical adsorption and chemical bonding to produce titanium nanopolymer coatings. The material has the following characteristics: (1) Due to the incorporation of titanium metal into its structure, it possesses excellent corrosion resistance and can withstand corrosion under various harsh environmental conditions. ⑵It features stable performance, resistance to natural aging, UV resistance, as well as resistance to electrochemical and cathodic corrosion; its service life is 2 to 5 times longer than that of traditional anti-corrosion coatings. ⑶The polymer itself is conductive and resistant to stray currents; it has the special ability to shield against electromagnetic, radar, and sonar waves, and is used for **camouflage**. ⑷It has excellent thermal conductivity, outperforms other anti-corrosion coatings, and is the preferred choice for use as a thermal conductive coating. ⑸Seawater corrosion test: Seawater has almost no corrosive effect on titanium nanocoatings, making them suitable for use in marine engineering protection. Therefore, the aforementioned outstanding features of titanium nanocoatings further emphasize the material’s ① strong resistance to penetration ； ②High corrosion resistance ； ③Good anti-scaling properties ； ④Good heat resistance ； ⑤Good water resistance ； ⑹It has good thermal conductivity. It can be applied in anti-corrosion fields such as petrochemical industry, marine vessels, and hydraulic engineering, offering the best cost-performance ratio for anti-corrosion protection. Titanium nano-coatings have been widely applied in various manufacturing and protection fields such as petrochemical industry, aerospace, offshore engineering, ships and containers, high-end equipment, and military industries.