Liquid separant for oriented silicon steel as well as preparation and spraying system and use method of liquid separant

The invention relates to a liquid separant for oriented silicon steel as well as a preparation and spraying system and a use method of the liquid separant. Firstly, pure water is added into a pure water preprocessor and heated; then the heated pure water is pumped into a separant preparation tank, then the separant solution is obtained through feeding, stirring and heating through a feeding opening, and finally the prepared separant solution is pumped to a spraying device to be aligned with the edge of the steel belt for spraying operation. The formula of the separant solution comprises 10%-20% of a compound B, 2%-7% of soluble chlorides such as MnCl2, 2%-5% of soluble sulfate such as CuSO4 and the like, and the balance of water. According to the method, B generated by slow decomposition of boric acid and sodium borate penetrates into a steel base to form a BN inhibitor with N in steel, Cl and SO4 < 2-> in chloride and sulfate erode the steel base, and SO4 < 2-> in the sulfate permeates into the steel bas