Method for preparing anhydrous aluminum fluoride through integrated purification and evaporation

The invention discloses a method for preparing anhydrous aluminum fluoride through integrated purification and evaporation. The method comprises the following steps: introducing crude hydrogen fluoride gas into a condenser for condensation to obtain hydrogen fluoride liquid and waste gas; and then transferring the hydrogen fluoride liquid into a rectifying tower, rectifying and evaporating the liquid into a fluidized bed, and reacting with aluminium hydroxide to obtain anhydrous aluminum fluoride, wherein the temperature of the outlet at the top of a rectifying tower is 20-22 DEG C. Accordingto the method, through system integration, a purification system and an evaporation system are integrated into one production system, so that coexistence of hydrogen fluoride in the system in different phase states is realized, continuous and stable production is ensured, and the whole production process is smoother; a hydrogen fluoride storage system is canceled, so that the storage amount of hydrogen fluoride in the who