Method for treating seed precipitated aluminum hydroxide size

Abstract

The invention provides a method for treating seed precipitated aluminum hydroxide size. The method comprises the following steps: pumping seed precipitated aluminum hydroxide size into a hydrocyclone by utilizing a submersible variable-speed pump in the process of producing alumina by a Bayer process; performing stage treatment on the seed precipitated aluminum hydroxide size by utilizing the hydrocyclone to obtain overflow aluminum hydroxide size and underflow aluminum hydroxide size; introducing the underflow aluminum size into a size tank for temporary storage; introducing the underflow aluminum hydroxide in the size tank into a flat-plate type filter for filtering and washing treatment to obtain mother liquor, flat-plate washing liquor and aluminum hydroxide; and roasting the aluminum hydroxide to obtain aluminum oxide, wherein the flat-plate washing liquor is returned to the submersible variable-speed pump and / or returned and mixed with the underflow aluminum hydroxide size. By adopting the method, the classification effect can be effectively improved, the product quality can be improved, vapor consumption and electricity consumption of Bayer process produced aluminum oxide can be reduced, and cost can be reduced.

Description

technical field [0001] The invention relates to the field of producing alumina by the Bayer process, in particular, the invention relates to a method for processing seed decomposed aluminum hydroxide slurry. Background technique [0002] For the production of alumina by the Bayer process, the classification effect of the finished product classifier is affected by the solid content of the feed, the concentration of the feed, the viscosity of the feed, and the temperature of the feed, resulting in a poor classification effect of the finished product, and a large number of fine particles are sent to the flat plate Filtration to reduce the grade of product alumina; the traditional process reduces the feed solid content and slurry viscosity of aluminum hydroxide slurry by adding the mother liquor (the mother liquor obtained after the seed decomposes aluminum hydroxide) to the submerged pump inlet. At the same time, add the mother liquor to the underflow box of the finished produc...

AI Technical Summary

Problems solved by technology

[0002] For the Bayer process of alumina production, the classification effect of the finished product classifier is affected by the comprehensive influence of feed solid content, feed concentration, feed viscosity, and feed temperature, resulting in poor classification effect of the finished product, and a large number of fine particles are sent to the flat plate Filtration to reduce the grade of product alumina; the traditional process reduces the feed solid content and slurry viscosity of aluminum hydroxide slurry by adding the mother liquor (the mother liquor obtained after the seed decomposes aluminum hydroxide) to the submerged pump inlet. At the same time, add the mother liquor to the underflow box of the finished classifier to reduce the solid content and viscosity of the flat slurry

However, the effect of this method is not ideal and needs to be further improved.

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