Maka ịnweta aluminum site na bauxite na-apụtakarị ịpụ aluminom trioxide na bauxite.Maka iru ebumnuche ahụ, enwere ụzọ atọ gụnyere: usoro acid, usoro alkali, usoro ngwakọta acid-base na usoro thermal.Otú ọ dị, a naghị eji usoro acid, usoro acid-base jikọtara ọnụ na usoro ikpo ọkụ n'ọtụtụ dị na ụlọ ọrụ n'ihi nchekwa na uru akụ na ụba.A na-eji usoro alkaline eme ihe na mmepụta mmepụta ihe.

Enwere ụzọ atọ maka mmịpụta alumina trioxide site na iji usoro alkaline nke bụ usoro calcination, usoro bayer na usoro jikọtara ọnụ.Anyị ga-ewere usoro calcination dịka ọmụmaatụ.

Usoro Calcination: Ịtinye ụfọdụ calcium carbonate n'ime bauxite, ihe bụ isi ihe mejupụtara ya bụ sodium aluminate ka a na-emepụta mgbe a gbasasịrị elu okpomọkụ na kiln rotary.N'ikpeazụ, a na-enweta alumina mgbe mgbasa, kristal na-esi nri.