Multi-stage evaporation purification kettle for phosphorous acid crystals

The utility model relates to the technical field of purification kettles, in particular to a multistage evaporation purification kettle for phosphorous acid crystals, which is characterized in that materials are discharged into a purification device through a storage device, the purification device heats and purifies the materials, and the purified materials are discharged into a storage hopper. The interior of a sleeve is heated through a plurality of sets of first heating plates, materials in a storage hopper are stirred and dried through slow rotation of a smashing device, after the materials are dried, caked materials are crushed through high-speed rotation of the smashing device, then the storage hopper is moved downwards to the position below the sleeve through stretching of a hydraulic cylinder, and the materials in the storage hopper are crushed through high-speed rotation of the smashing device. Workers can take out the materials, so that the labor amount of the workers is reduced, and the practicabi