The Bayer process uses high-grade bauxite ore, which is mixed with alkaline solution, lime milk, and mother liquor in proportion and ground into slurry. Sodium aluminate is then directly leached under corresponding temperature and pressure conditions after pre-desilication, followed by red mud separation, seeding decomposition, and calcination of aluminum hydroxide to produce finished alumina. For high-grade ores with an aluminum-to-silicon ratio greater than 7, the Bayer process is the preferred production method.