System and method for preparing vanadium battery high-purity electrolyte

A system and method for preparing a vanadium battery high-purity electrolyte, using vanadium oxytrichloride as a raw material; preparing low-valence vanadium oxide having an average vanadium valence of 3.5 by means of liquid phase hydrolysis and fluidised reduction, adding clean water and sulphuric acid dissolution, and further using ultraviolet activation to obtain an electrolyte that can be directly used for a new all-vanadium redox flow battery stack; the sensible heat and latent heat of the high-temperature exhaust gas are recovered by means of reduction fluidised bed high temperature exhaust combustion of pre-heated powder vanadium material and the sensible heat of the reduction product is recovered by means of heat transfer of the reduction product and fluidised nitrogen; implementing accurate regulation and control of the state of the reduction product by arranging internal components in a reduction fluidised bed (3) and using ultraviolet to activate the vanadium ions improves electrolyte activity; the present system and method have the advantages of a short procedure, efficiency and cleanliness, and stable product quality, and can be used in large-scale industrial production.