graphite electrode rp500
Selection of raw materials for different graphite electrode rp500 and graphite products
For different types of carbon graphite products, there are special use requirements and quality indicators according to their different uses. When considering what raw materials should be used to produce a certain variety of graphite electrode rp500 and graphite products, we should first study how to meet these special use requirements and quality indicators. For example, in the production of graphitized products, petroleum coke and pitch coke, which are easily graphitized, must be used as raw materials; when producing anode paste for aluminum electrolysis, because the ash content of the anode paste has a direct impact on the quality of aluminum, it is necessary to use petroleum with low ash content. Coke and pitch coke are raw materials. Similarly, pre-baked anodes used in place of anode paste must also use petroleum coke and pitch coke as raw materials. There are no strict regulations on ash content, and other products that do not need to be graphitized can use anthracite and metallurgical coke as the main raw materials. If necessary, you can add low-minimum ash raw materials to reduce ash and improve electrical conductivity.
(1) Selection of raw materials for conductive electrodes used in electric metallurgical processes such as electric furnace steelmaking. Conductive electrodes used in electric metallurgical processes such as electric furnace steelmaking must have good electrical conductivity, appropriate mechanical strength, good resistance to rapid cooling and heating at high temperatures, corrosion resistance, and relatively low impurity content. At present, there are four ways to select raw materials for the production of carbon or graphite conductive electrodes.
① All low-ash raw materials such as petroleum coke and pitch coke are used to produce high-quality graphite electrode rp500. However, the production of graphite electrode rp500 requires more equipment, long process flow, and technically more complicated. The production of 1t graphitized electrode consumes 6000~.h.
②Use high-quality anthracite or metallurgical coke as raw materials to produce carbon electrodes. The production of carbon electrodes does not require graphitization equipment, and the other production processes are the same as the production of graphite electrode rp500. The conductivity of the carbon electrode is much worse than that of the graphite electrode rp500. The resistivity is generally 2 to 3 times larger than that of the graphite electrode rp500. The ash content varies depending on the quality of the raw material, generally about 10%. But after special selection, the ash content of anthracite can be reduced to less than 5%. Using this selected anthracite to make products, such as further graphitization, can reduce the ash content of the product to about 1.0%. Carbon electrodes can be used to smelt products such as ordinary electric furnace steel and ferroalloys.
③Use natural graphite as raw material to produce natural graphite electrode rp500. Natural graphite must be carefully selected to reduce its ash content before it can be used. The resistivity of the natural graphite electrode rp500 is about twice that of the graphitized electrode. However, the mechanical strength is relatively low, and it is easy to break during use. In areas with abundant natural graphite production, natural graphite electrode rp500 can be produced for smelting ordinary electric furnace steel in small electric furnaces in this area. When using natural graphite to produce conductive electrodes, the equipment and processes used are easier to solve and master.
④The cutting chips or waste products during the processing of graphitized electrodes are crushed and ground to produce regenerated electrodes (or called graphitized broken electrodes). This product has a low ash content (about 1%), and its conductivity is worse than that of graphitized electrodes. The resistivity is about 1.5 times the resistivity of graphitized electrodes, but the use effect is better than that of the natural graphite electrode rp500. . Although the production of recycled graphite electrode rp500 is technically easy to master and the equipment is relatively easy to solve, the source of raw materials for graphitization and crushing is limited, so this approach is not the direction of development.
(2) The choice of the original family for the electrolytic salt industry conductive anode. The conductive anode used in the electrolytic salt industry must have good conductivity, compact structure and high mechanical strength, and it is not easy to be corroded and oxidized by the electrolyte. Therefore, petroleum coke and pitch coke are currently used to produce graphitized anodes. After selection, anthracite with very low ash content can also be used to produce graphitized cathodes, but its resistivity is relatively large, and the ash content is also larger. Such anodes have a relatively short service life in the electrolytic cell.
(3) Selection of raw materials for carbon refractory materials for various metallurgical furnaces. The carbon refractory materials used in various metallurgical furnaces, such as the bottom carbon block and the side carbon block used in the carbon block and aluminum electrolytic cell for ironmaking blast furnaces, require high mechanical strength and corrosion resistance, as well as a low coefficient of thermal expansion. , The bottom carbon block used in aluminum electrolysis cell is also required to have better conductivity, but the ash content is generally not strict, so high-quality anthracite and metallurgical coke can be used as raw materials. In order to improve the conductive parts and thermal conductivity of the carbon block, some graphitized crushed or graphitized metallurgical coke can be appropriately added to the batch.
(4) Electrode paste. Electrode paste is a conductive material (continuous self-baking electrode) used in submerged electric furnaces for smelting ferroalloys or producing chemical products such as calcium carbide and yellow phosphorus. It has a relatively low current density and a slightly higher ash content, which has little effect on product quality, and has a wide range of raw materials.
Therefore, in the production of electrode paste, high-quality anthracite coal and metallurgical coke are generally used, while raw crushing of various products and other production return materials are often added. Metallurgical coke or metallurgical coke plus natural graphite can also be used to produce electrode paste, but this kind of electrode paste consumes a lot in use. Many large-scale calcium carbide furnaces and ferroalloy furnaces have enclosed electric furnaces in order to improve operating conditions and recover combustible gas. The electrode paste used in this enclosed electric furnace requires a faster sintering speed, better conductivity and lower ash content. Therefore, when manufacturing the electrode paste used in this enclosed electric furnace, a certain amount of raw materials such as petroleum coke, graphitized crushed or graphitized metallurgical coke should be added, and a binder with a slightly lower softening point (about 50°C) should be used. As a manufacturer of graphite electrode rp500, our company mainly produces ordinary power graphite electrode rp500, high power graphite electrode rp500, ultra-high power graphite electrode rp500 and graphite products.