Method for melting green silicon carbide from smokeless ultra low-ash pure coal and green silicon carbide prepared therefrom

Abstract

The invention provides a novel method for preparing green silicon carbide and the green silicon carbide prepared therefrom. The method first employs smokeless ultra low-ash pure coal to melt green silicon carbide; a main carbon raw material of petrol coke used in a prior art is substituted, so as to substantially reduce production costs of green silicon carbide and control difficulty of a melting process and enhance product quality; besides, the ultra low-ash pure coal has stable physical and chemical indexes and resource, and can satisfy long-term production.

Description

technical field [0001] The invention relates to the field of crystal preparation. More specifically, the present invention relates to a new method for preparing green silicon carbide and the green silicon carbide prepared thereby. Background technique [0002] Silicon carbide is a strong covalent bond compound material formed by the combination of carbon atoms and silicon atoms. The special structure makes silicon carbide have hardness and grinding performance comparable to diamond, and also has high temperature resistance, strong acid and alkali resistance, and corrosion resistance. , oxidation resistance and other properties, widely used in all walks of life. [0003] Silicon carbide includes black silicon carbide and green silicon carbide. Its hardness is between corundum and diamond, its mechanical strength is higher than that of corundum, and it is brittle and sharp. Among them: black silicon carbide is made of quartz sand, petroleum coke and high-quality silica as th...

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Problems solved by technology

Petroleum coke is extracted from petroleum. With the increasingly tight supply of petroleum and the improvement of refining technology, petroleum coke is used as a by-product of petroleum, resulting in limited supply. The price of petroleum coke is rising year by year. Now the petroleum coke market The price is about 3,000 yuan / ton, causing the raw material cost of green silicon carbide to continue to rise, and the production cost of green silicon carbide to rise

And because the quality of petroleum coke is extremely unstable (petroleum coke has many coking methods and complex processes, and is affected by factors such as the difference in the main product of the coking plant and human operation, petroleum coke is a by-product, and the physical and chemical indicators are not the main control indicators of the coking plant. , so the fixed carbon, ash, volatile matter, sulfur and other quality indicators of each batch of imported petroleum coke in the silicon carbide plant are quite different), which makes the smelting efficiency and product quality of green silicon carbide not guaranteed, resulting in quality reduction, etc. At the same time, it makes the control of the smelting process more difficult, and the smelting process must be adjusted frequently, which in turn causes the green silicon carbide smelting process to be extremely unstable, and it is very likely that the furnace will be sprayed, and it may also cause unstable furnace conditions and electrode damage.

In the end, the normal progress of the smelting work cannot be guaranteed

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