Energy-saving-type metallurgical waste acid recycling processing method and device

The invention discloses an energy-saving-type metallurgical waste acid recycling processing method and a device. The energy-saving-type metallurgical waste acid recycling processing method comprises following steps: metallurgical waste acid is subjected to precipitation, low temperature acid water separation, crystallization, and solid-liquid separation successively, precipitated ferrous sulfate crystals are collected, and high concentration sulfuric acid obtained via processing is collected and stored in a sulfuric acid storage tank for production recycling. According to the energy-saving-type metallurgical waste acid recycling processing method, a low temperature evaporation and cooling bi-directional parallel physical method is adopted so separate sulfates and sulfuric acid in waste acid, no chemical agent is added in waste acid processing process, water evaporation in waste acid is reduced, supersaturation and crystallization of ferrous sulfate in waste acid are realized, the precipitated ferrous sulfate