The key technologies of "shredding and crushing + low-temperature electrolyte drying + organic pyrolysis + separation + multi-high value metal roasting", such as multi-stage composite treatment, precise control of temperature field and flow field, continuous automatic operation of equipment and collaborative treatment of multi-pollutants in reaction process, have been developed. A combined process system with the core of "low temperature drying of electrolyte, pyrolysis of organic matter and roasting of high value metal" is established, which can realize the process purpose of "waste power battery → complete separation of black powder, copper and aluminum, and priority extraction of lithium by roasting of black powder".