Red mud dealkalization method realized through phase state control

The invention relates to a red mud dealkalization method realized through phase state control. The method comprises the following steps: pretreatment: drying raw material red mud; mixing and dissolving: dissolving the dried and crushed red mud; freezing crystallization: cooling crystallization; overall freezing: completely freezing the mixture; melting and washing: melting the frozen material; collecting the eluting agent; repeatedly leaching; deionizing and leaching; machining is completed; the method disclosed by the invention has the beneficial effects that the granularity of the red mud is extremely fine, so that the dosage of an eluting agent is large and the eluting agent is not easy to fully react with the red mud by adopting a conventional eluting method; a freeze-thaw cycle method is adopted, so that the eluting agent can be effectively and fully contacted with the red mud, and structural alkali in the red mud is destroyed and changed into free alkali, so that the purpose of dealkalization is achieve