The utility model belongs to the technical field of single nickel salt evaporation equipment, concretely relates to a device for nickel sulfate solution evaporates in succession, including condense water preheater, the leading pre -heater of steam and flash tank, the leading pre -heater of steam is connected with solution feeding pump line, leading pre -heater of steam and primary heater tube coupling, primary heater and secondary heater tube coupling are equipped with the forced circulation pump on the pipeline between primary heater and the secondary heater, secondary heater and flash tank tube coupling, flash tank and vapor compressor tube coupling, vapor compressor respectively with primary heater and secondary heater tube coupling, the utility model discloses a repeated compression of flash steam is used, replaces most live steam, and live steam only is used for, and the system is first to be driven, supply calorific loss and supply and import and export the required heat content of the material difference in temperature to reduce the live steam consumption by a wide margin, reach energy -conserving purpose.