Production Process Of Graphite Electrode

The calcining equipment mainly includes pot calciner, rotary kiln and electric calciner. Calcination quality control indicators are that the true density of petroleum coke is not less than 2.07g/cm3, the resistivity is not greater than 550μΩ.m, the true density of needle coke is not less than 2.12g/cm3, and the resistivity is not greater than 500μΩ.m. Crushing and batching of raw materials

Before batching, the bulk calcined petroleum coke and needle coke must be crushed, pulverized and sieved.

Secondary crushing is usually to further crush the material of about 50mm to the particle size material of 0.5-20mm required for batching through jaw crusher, hammer crusher, roller crusher and other crushing equipment.

Grinding is the process of grinding carbonaceous raw materials to powdery small particles with a particle size of 0.15mm or 0.075mm or less by hanging stick ring roller mill (Raymond mill), ball mill and other equipment.

Screening is the process of dividing the crushed material with a wide size range into several particle sizes with a narrow size range through a series of sieves with uniform openings. The current electrode production usually requires 4-5 particle sizes and particle sizes. 1-2 powder grades.

Batching is a production process in which aggregates, powders and binders of various particle sizes are calculated, weighed and focused according to the formula requirements. The scientific suitability of the formula and the stability of the batching operation are one of the most important factors affecting the product quality index and performance.

The formulation needs to determine five aspects: ① select the type of raw material; ② determine the proportion of different types of raw materials; ③ determine the particle size composition of solid raw materials; ④ determine the amount of binder; ⑤ determine the type and amount of additives.

Kneading: The process of kneading quantitative carbonaceous granules and powders of various particle sizes and quantitative binders at a certain temperature to form a plastic paste is called kneading.

Kneading process: dry mixing (20-35min) wet mixing (40-55min)

The function of kneading: ①When dry mixing, the various raw materials are mixed evenly, and at the same time, the solid carbonaceous materials of different particle sizes are evenly mixed and filled to improve the compactness of the mixture; ②After adding coal tar pitch, the dry material and asphalt are mixed evenly , liquid asphalt evenly coats and infiltrates the surface of the particles to form a layer of asphalt bonding layer, which bonds all materials together, and then forms a homogeneous plastic paste, which is conducive to molding; ③Part of the coal tar pitch is soaked into the carbonaceous material Internal voids further increase the density and cohesiveness of the paste.

Molding: The molding of carbon materials refers to the process in which the kneaded carbon paste is plastically deformed under the external force applied by the molding equipment, and finally forms a green body (or raw product) with a certain shape, size, density and strength. process.