The zinc sulfate evaporator has strict requirements for material selection, mainly due to the corrosive nature of zinc sulfate waste liquid, so the selected material must have anti-corrosion properties. The following are the specific requirements for selecting materials for zinc sulfate evaporators:

      1. Heating Tube

      Material selection: The heating tube should be made of graphite material. Graphite material has excellent corrosion resistance and high temperature resistance, which can maintain stability during the evaporation process of zinc sulfate and is not easily affected by corrosion, thus ensuring the long-term stable operation of the evaporator.

      2、 Separators and Crystal Growth Chambers

      Material selection: The separator and crystal growth chamber should be made of carbon steel enamel. Carbon steel enamel is made by coating a layer of enamel glaze on the surface of carbon steel and firing it at high temperature. This material not only has the strength of carbon steel, but also the corrosion resistance and smoothness of enamel, which can effectively prevent the corrosion of equipment by zinc sulfate waste liquid and facilitate the growth and separation of crystals.

    III. Condenser

      Material selection: The condenser cooler should use graphite modified polypropylene absorber. Graphite modified polypropylene is a composite material that combines the advantages of graphite and polypropylene, possessing both the corrosion resistance and thermal conductivity of graphite, as well as the formability and chemical resistance of polypropylene. This material can exhibit excellent performance in the condensation cooling process of zinc sulfate evaporators, ensuring evaporation efficiency while extending the service life of equipment.

      Fourth, Other Considerations

      Temperature control: The solubility of zinc sulfate varies with temperature, so it is necessary to control the discharge temperature reasonably when designing the evaporator to avoid a large amount of water being carried away by the crystals. At the same time, it is necessary to consider the increase in boiling point of zinc sulfate in order to select suitable compressors and evaporation processes.

      System stability: The design of the evaporator should ensure the stability of the system operation, avoiding problems such as blockage of the heating chamber tubes that may affect the evaporation rate or cause the system to malfunction.

      Equipment lifespan: In order to extend the service life of the equipment, higher-level anti-corrosion materials such as TA2 material, composite titanium plate, and 2205 duplex steel can also be considered for key components such as heat exchangers.

      In summary, the material selection requirements for zinc sulfate evaporators are strict, and materials with excellent corrosion resistance and high temperature resistance must be selected to ensure the long-term stable operation and efficient evaporation of the evaporator.