Calcium carbide is  one of the basic raw material of organic synthesis industry.It is also an important raw material of acetylene industry.
(1)The reaction of Calcium Carbide with water, producing acetylene and calcium hydroxide.[CaC2 + 2 H2O → C2H2 + Ca(OH)2].
    This reaction was the basis of the industrial manufacture of acetylene, and is the major industrial use of Calcium Carbide.
    eg.synthetize rubber,synthetic resin,acetone,ketene and carbon blace.Meanwhile oxygen-acetylene flame is widely used in metal welding and cutting.
(2)Heating powdered Calcium Carbide and nitrogen to producing calcium cyanamide,which can react with sodium chloride producing black cyanide. black cyanide is used in gold mining and non-ferrous metal industry.
(3)Steelmaking: as a powerful deoxidizer at ladle treatment facilities.
(4)Calcium carbide is used in carbide lamps, in which water drips on the carbide and the acetylene formed is ignited. 
(5)In the ripening of fruit, Calcium Carbide is sometimes used as source of acetylene gas, which is a ripening agent similar to ethylene.