Method for promoting settling separation of Bayer red mud

Abstract

The invention relates to a method for promoting settling separation of Bayer red mud by the addition of crystal seed in the pre-desilication process to improve settling separation performance of the red mud. The method for promoting red mud separation is characterized in that during the pre-desilication working process in the Bayer alumina production, pulp after pre-desilication is added into the original pulp which hasn't undergone pre-desilication as sodium aluminosilicate hydrate crystal seed so as to promote settling separation of Bayer red mud. The method provided by the invention is used to effectively promote settlement and compression performance of red mud generated from kaolinite bauxite, simultaneously improve filtering performance of red mud and raise leaf filtration production power. The method is suitable for Bayer alumina production. In addition, domestic bauxite resources are generally characterized by high silicon, and high aluminium and the settlement performance of red mud seriflux after digestion is not good. Therefore, the method has a very good application prospect.

Description

technical field [0001] The invention relates to a method for promoting sedimentation and separation of Bayer process red mud, which relates to a method for sedimentation and separation of Bayer process red mud by adding seed crystals in a pre-desiliconization process to improve the sedimentation and separation performance of red mud. technical background [0002] At present, in industrial production, pre-desilication operation technology is adopted for kaolinite-containing hard-settled bauxite (stirring the raw ore slurry at 90--105°C for 6-12 hours, so that the silicon minerals can be transformed into sodium-silicon as completely as possible. slag) to reduce or prevent silicon slag scabbing in the high-pressure dissolution process. [0003] With the shortage of ore resources for alumina production and the decline of ore grades, high-efficiency and continuous operation of production is often restricted by the muddy process of the Bayer process sedimentation tank, and the im...

AI Technical Summary

Problems solved by technology

In the case of insufficient silicon slag seeds, it is easy to generate a large amount of fine sodium-silicon slag, resulting in poor settling speed and compression performance of the settled red mud, resulting in falsely high mud layer in the settling tank, and resulting in leaf filter and filter overfeed in the subsequent process Difficult to make stable operation of high pressure dissolution system

[0005] For this reason, it has been proposed to roast bauxite at a temperature of about 500°C, which can reduce the hydrophilicity of the red mud after dissolution and improve the sedimentation performance; The problem is not adopted in industrial production