Method for comprehensively recovering scandium and titanium by leaching red mud with titanium white waste acid

The invention relates to a method for comprehensively recovering scandium and titanium by leaching red mud with titanium white waste acid, which comprises the following steps: at ordinary pressure, dipping red mud with titanium white waste acid having a liquid-to-solid ratio of 4.0-6.0, performing secondary acid dipping on the leached slag, dealkalizing the secondary acid dipping slag, further performing strong magnetic separation to obtain iron-containing ores and tailings, and performing secondary strong magnetic separation on the iron-containing ores to obtain iron concentrated ores and middlings; extracting the leaching solution, performing back extraction, dissolving in acid to perform hydrolysis, performing secondary extraction, removing impurities, performing secondary back extraction, dissolving in hydrochloric acid, adding oxalic acid to precipitate, and calcining to obtain a scandium oxide product; dissolving the back extraction slag in sulfuric acid, and performing hydrolysis under the conditions o