Method for comprehensively recovering carbon, lithium, aluminum and fluorine from aluminum electrolysis carbon residues

The invention provides a method for comprehensively recovering carbon, lithium, aluminum and fluorine from aluminum electrolysis carbon residues, and belongs to the technical field of comprehensive utilization of resources. The method comprises the steps that firstly, carbon is recycled through flotation, then decarburized tailings and a reconstruction agent are mixed, obtained ore phase reconstruction ore pulp and sulfuric acid are mixed, stirring leaching and solid-liquid separation are carried out, and leachate and a filter cake are obtained; after the filter cake and water are mixed and separated, washing liquid and leaching residues are obtained; adding potassium sulfate into the leachate, and reacting to obtain aluminum potassium sulfate crystals and aluminum-removed liquid; and adding lime into the aluminum-removed solution, separating, adding trisodium phosphate into the obtained purified solution, separating to obtain a lithium phosphate crude product, and further washing to obtain a lithium phosphat