Ferrosilicon and Metallurgical Grade Silicon

Manufacture of metallurgical grade silicon by reduction of quartzite with coke in an electric-arc furnace 

Tabie 3.4-1. Specifications of quanz for the manufacture of metaliurgical grade silicon. 

Sulfur-, phosphorus- and arsenic- contents are undesirable, since they form poisonous flue gases. High Al203-contents lead to the formation of sticky slags, which can contaminate the end product. 

In the production of ferrosilicon the Moeller iron in the charge is added in the form of turnings or shredded iron. For silicon-contents above 45%, a shaft electric furnace is used with a power of 8 to 40 MW, whose substructure is lined with carbon bricks. The undesirable formation of SiC is avoided by rotating or oscillating the furnace. It operates 

Manufacture of ferrosilicon by addition of iron as iron turnings or shredded iron 

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