Method for firing calcium oxide from carbide slag

The invention discloses a method for firing calcium oxide from carbide slag. The method comprises the following steps of: preheating the carbide slag with a water content of less than or equal to 2 percent by using preheating unit, decomposing the carbide slag in a decomposing furnace to obtain calcium oxide, cooling the calcium oxide by using a cooling unit, and feeding the calcium oxide into a storage tank for later use, wherein hot air obtained after heat exchange of hot flue gas generated by a hot blast stove is adopted as a heat source, the hot flue gas at 800-850 DEG C provided by the hot blast stove is subjected to heat exchange through a non-metal heat exchanger, then the temperature is reduced to 180-200 DEG C, the flue gas is discharged into the atmosphere after being subjected to desulfurization, denitration and dust collection, and the hot air is heated to 600-650 DEG C and enters the decomposing furnace to serve as a carbide slag decomposing heat source. According to the invention, the hot air is