1. Standard Paste
The electrode pastes of THD-4 and THD-5 in the national standard GB10130-88 are used in open calcium carbide furnaces. This electrode paste uses ordinary calcined anthracite and metallurgical coke as the main raw materials, and uses medium temperature pitch as the binder to have higher ash content. , The resistivity is large, the sintering speed is slow, but the price is low.
2. Airtight paste
In the national standard GB10130-88, THD-2 and THD-3 electrode pastes are used in closed submerged arc furnaces. This kind of furnace surface can be closed to recover gas and improve working conditions. The electrode pastes are required to have good sintering properties. The airtight paste generally uses ordinary calcined anthracite, artificial graphite crushed, and petroleum coke as the main raw material. At the same time, a certain amount of coal tar is added to the coal tar to reduce the softening point of the binder. It has the characteristics of electrical conductivity, good thermal conductivity, low ash content, fast sintering speed, and high price.
3. Special paste:
In recent years, my country’s submerged arc furnaces are developing towards large-scale confinement. During the “Seventh Five-Year Plan” and “Eighth Five-Year Plan” period, the Ministry of Chemical Industry introduced 10-12 large-scale confined thermal furnaces from Norway, Japan, and West Germany. Compared with traditional furnaces, such large-scale closed submerged arc furnaces have the advantages of low energy consumption, good working conditions, stable product quality, reduced production costs, and less environmental pollution. A broken electrode accident will cost more than 100,000 yuan, so there are strict technical requirements for the electrode paste used.