This article Xingnong Machinery will analyze for you the reasons for the corrosion of the cylinder of lime rotary kiln equipment. ●Lime rotary kiln equipment cylinder corrosion is the main reason for cylinder replacement in lime plants. Many pre-decomposed lime rotary kilns have cylinder corrosion problems, which are generally discovered during equipment overhaul, kiln shutdown maintenance, and replacement of kiln lining refractory bricks. The flake corrosion products removed from the inner wall of the cylinder have a multi-layered structure close to each other. One side of the cylinder is reddish brown and black, and each layer has bright crystal dots scattered or distributed in sheets.
The lime rotary kiln barrel is corroded and usually peels off in flakes. The rust flakes are loose and brittle. Measured by an ultrasonic thickness gauge, it can be found that the barrel has been thinned to varying degrees, and some will appear on the inner surface of the barrel. Circular uneven grooves appear. For example, grooves are often found on the inside of the cylinder at the large gear in the front section of the lime rotary kiln. The most serious area of cylinder corrosion is the cylinder near the large cone in the transition zone of the lime rotary kiln. The annual corrosion rate is as high as ~
●Analysis of the causes of lime rotary kiln cylinder corrosion
Analysis of corrosion flakes found that, The main components of the rust layer are iron oxides and small amounts of chlorides and sulfides. Therefore, the corrosive substances on the inner wall of the kiln barrel are oxygen, sulfur and chloride.
High-temperature oxidation causes corrosion of the inner wall of the cylinder
The cylinder of lime rotary kiln is generally made of ordinary steel, and ordinary steel is not resistant to high-temperature oxidation. At ~℃, visible protective corrosion is produced. oxide film. However, the structure of this oxide film is loose and it is difficult to prevent the metal cylinder from being further oxidized, especially when the temperature is higher. For example, the annual oxidation rate of steel at ℃ is as high as ℃. The temperature of the cylinder in the transition zone of the lime rotary kiln is usually ~℃, or even higher temperatures, therefore, oxidation corrosion on the inner surface of the cylinder is inevitable.
High-temperature sulfidation corrosion is different from high-temperature oxidation corrosion. This kind of corrosion can occur under the metal surface, and the subcutaneous corrosion products contain unoxidized metal. The hot corrosion temperature should be ~℃, but in media containing strong corrosion, high-temperature vulcanization may occur at around °C, causing the inner wall to be corroded.
High-temperature chlorination causes corrosion of the inner wall of the cylinder
According to reports, in high-temperature environments, chlorine and chlorides have a particularly strong corrosive effect on steel. Under chlorination conditions, a lower boiling point (℃) will be formed. It is volatile, thus aggravating the corrosion of the lime rotary kiln barrel.
It should be pointed out that during the process of calcining lime clinker in a lime rotary kiln, the atmosphere in the kiln is very complex. Various factors that cause cylinder corrosion exist almost at the same time and work together to make the cylinder of the lime rotary kiln unbearable. Corroded by the burden.
Henan Xingnong Machinery is a professional manufacturer of lime rotary kiln equipment. It provides a wide range of high-quality and high-yield lime rotary kiln equipment as well as related coolers, preheaters and other kiln equipment, and undertakes the design and construction services of various large-scale lime rotary kilns.
Gongyi Xingnong Machinery Manufacturing Co., Ltd. is a leading manufacturer and supplier of mineral processing equipment in China. We specialize in the production and operation of high-quality mineral processing equipment, crushing equipment, rotary kiln equipment and dryer equipment. The main products of mineral processing equipment include ball mill, energy-saving ball mill, cone ball mill, overflow ball mill, grid ball mill, cement ball mill, baseball mill, crusher, jaw crusher, compound crusher, impact crusher, new crusher, dryer Dryers, new dryers, slime dryers, fly ash dryers, lignite dryers, desulfurization gypsum dryers, Mongolian coal dryers, ore washers, spiral washers, classifiers, Flotation machine, magnetic separator, etc. Rotary kiln equipment includes carbon rotary kiln, ceramsite sand rotary kiln, limonite rotary kiln, hematite rotary kiln, kaolin rotary kiln, cement rotary kiln, and reduced iron rotary kiln. These products are widely used in mining, metallurgy, electric power, highways, railways, water conservancy, building materials and other fields.
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Xingnong brings you an analysis of the causes of lime rotary kiln cylinder corrosion