Calcium carbide is made from a mixture of lime and coke at
above ***0C. It is made in an electric arc furnace.The pure
material is colorless, however pieces of technical grade calcium
carbide are grey or brown and consist of only ****5% of
CaC2. A very high temperature is required for
reaction. The carbide produce is then crushed to smaller
lumps typically around ****0 mm size. The content of CaC2 content
is measured by measuring the amount of acetylene gas produced
on hydrolysis. Typical standards are **5L/kg and **0L/kg.
Impurities in the carbide produced are phosphides and
sulphides.Its main use industrically is in the production of
acetylene and calcium cyanamide.In China, acetylene derived from
calcium carbide remains a raw material for chemical industry,
in particular for the production of polyvinyl chloride. Locally
produced acetylene is more economical than using imported oil.
Production of calcium carbide in our factory had a dramatic
increase during last 5 years.