China's current production of hydrofluoric acid or fluorite - based sulfuric acid route, fluorosilicic acid feed line development is still the starting stage.

Process Description: wet calcium fluoride into the rotary oven drying (if purchased dry Calcium fluoride, this step can be omitted. ), Calcium fluoride fed by transport means, storage tank, metered into the pre-reactor; the reactor is from nicotinic acid are metered into the pre-reactor, the chemical reaction, generating hydrofluoric acid gas, unreacted subsequent CaF2 + H2SO4 into the inner indirectly heated rotary kiln reaction was continued to fully complete the reaction.

The crude hydrofluoric acid  produced by the reaction is attracted to pre-wash scrubber with sulfuric acid to remove dust, moisture, desulfurization isolated high-melting impurities such as H2SO4 and HSO3F; then into the condenser, the hydrogen fluoride gas is liquefied through cooling crude liquid hydrogen fluoride. Sulfuric acid washed into niacin reactor.

The crude hydrogen fluoride liquid into the distillation column and degassing tower to further remove SO2-, SiF4-, H2SO4, H2O and inert gas, purified to obtain purified liquid hydrogen fluoride, hydrogen fluoride analysis after passing into the tank, it can be sold as a product.

A condenser and a fine slip column non-condensable gas contained in the residual hydrofluoric acid  is absorbed in H2SO4 sulfuric acid washing vessel into the process cycle.