The industrial production method of silicon carbide is to use high-quality quartz sand and petroleum coke in the resistance furnace. A series of products of silicon carbide are made of silicon carbide blocks. The original silicon carbide block is crushed and sieved to form silicon carbide particle size sand, which is divided into silicon carbide powder through Raymond Mill screen;
The company can provide all kinds of SiC raw block, segment sand, No. sand, fine powder and micro powder products to the market. The content of high-quality and dense silicon carbide products is more than 98.8%, the specific gravity is more than 3.2g/m3, and the bulk density is more than 1.62g/m3. The product has high toughness, high strength and high purity. Particle size sand and powder products have small impurity pollution, excellent physical and chemical indexes and superior particle shape. The products have strong competitiveness in the market.
Silicon carbide raw block is a kind of artificial diamond super hard material which is smelted by high temperature resistance furnace. It is made of quartz sand, petroleum coke (coal coke), wood chips and so on. Relying on the anthracite with the characteristics of low ash, low sulfur, low phosphorus, high calorific value, high mechanical strength, high chemical activity and high specific resistance, the ultra-low ash and low sulfur refined coal products are produced by washing and processing the coal. Using high-purity silica as raw material, the silica sand with uniform particle size and more than 99% SiO2 content was produced by washing.
Production of SiC raw block:
(1) crushing of raw materials
A hammer crusher is used to crush petroleum coke to the required particle size.
(2) batching and mixing
Batching and mixing are the process of weighing and mixing according to the specified formula. The batching platform and concrete mixer are used in the project, and the petroleum coke and quartz sand are batched and mixed according to the process requirements.
(3) preparation of silicon carbide furnace:
The preparation of electric furnace is to repair and arrange the furnace used last time, so as to put it into use again. The operation content includes cleaning the furnace bottom material, trimming the electrode, cleaning the furnace wall and repairing, removing the loading force and 1 stop, inspecting and removing other defects of the furnace.
Charging is to fill reaction material, heat preservation material and furnace core material into the furnace according to the specified charge type, position and size, and to build the furnace side wall with heat preservation and charging function.
(5) power transmission and smelting of silicon carbide:
After the smelting furnace is connected with the transformer, the power can be transmitted. At the beginning of power transmission, open fire was put into operation for 15 minutes to ignite Co, and the smelting process lasted for 170 hours.
After the furnace is shut down, the silicon carbide smelting furnace will be cooled naturally, then the furnace will be raked (the furnace wall will be unloaded and the spent materials will be raked), and the natural cooling will continue.
(7) discharge classification
The classification of silicon carbide is a process in which the crystal block and graphite are removed from the furnace and the first grade, second grade and graphite are separated. The out of furnace classification of silicon carbide adopts the method of out of furnace classification. The crystallizer is split manually, and the massive crystallizer is transported to the classification field for manual classification.