Series alumina production process

Abstract

The invention belongs to the technical field of mineral processing, and particularly relates to a series alumina production process. The process is carried out according to the following steps: (1) uniformly mixing part of a Bayer method decomposition mother liquor with a red mud, adding an iron source, caustic soda and lime to prepare a slurry liquid to be dissolved out; (2) performing solid-liquid separation on a slurry liquid after dissolving out to obtain a solid secondary red mud and a dissolved out separation liquid; washing the solid secondary red mud with hot water to obtain a byproduct secondary red mud filter cake and a secondary red mud washing liquid; and mixing and then sending the dissolved out separation liquid and the secondary red mud washing liquid to a circulating motherliquor preparing procedure in a Bayer method process, performing mixing with the remaining Bayer method decomposition mother liquor after evaporation, and then entering a dissolving out and dilutionprocedure as a circulating mother liquor; and (3) mixing the circulating mother liquor with a bauxite, and then producing qualified alumina through conventional Bayer method procedures. According to the process, high-alkali dissolving out of a Bayer method red mud is carried out, an extraction rate of alumina is improved, consumption of an alkali is reduced, and thus waste-free discharge and comprehensive utilization of alumina production are realized.

Description

technical field [0001] The invention belongs to the technical field of mineral processing, and in particular relates to a tandem alumina production process. Background technique [0002] The alumina production method widely used in industry is the alkali method, and the production of alumina by the alkali method is subdivided into various processes such as Bayer method, sintering method and Bayer sintering combined method. The Bayer method has simple process, low energy consumption, good product quality and low cost, but it is more suitable for processing bauxite with higher grade (A / S>5). The sintering method is suitable for processing low-grade bauxite, but the process is more complicated, and the energy consumption and cost are higher than those of the Bayer method. [0003] The Bayer sintering combined method is applied in some cases, which can get better economic results than the Bayer method or sintering method alone, so that the bauxite resources can be more fully...

AI Technical Summary

Problems solved by technology

However, in the current mature red mud utilization technology, the method of using red mud as a general basic raw material as a whole has low added value of the product; the sintering method has many problems such as narrow sintering temperature range, difficult control, high energy consumption, and poor economy. Problem: The process of acid treatment of red mud has strict requirements on equipment and is difficult to industrialize

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