Method for treating filter cakes of leaf filter

Abstract

The invention provides a method for treating the filter cakes of a leaf filter. At present, the flow of treating the filter cakes of the leaf filter of a Bayer process alumina refinery directly leads the filter cakes and the adherent liquid obtained by the extract backflush and automatic mud-discharging technique unloading the leaf filter to the primary red mud washing and sedimentation tank. The method affects the red mud sedimentation and separation effect of the primary washing and sedimentation tank, and increases the adherent alkali of discharge red mud. The method first leads the the filter cakes and the adherent liquid obtained by the extract backflush and automatic mud-discharging technique unloading the leaf filter to a post-dilution tank, and then carries out subsequent treatment. The invention can help to improve the sedimentation proformance of the red mud washing and sedimentation tank and reduce the loss of the adherent liquid when the red mud is washed for the last time.

Description

technical field [0001] The invention relates to the improvement of the alumina production process, in particular to a method for treating filter cake of a leaf filter. Background technique [0002] At present, the filter cake treatment process of the leaf filter of the Bayer process alumina plant (see figure 1 ) is to unload the filter cake of the leaf filter using semen recoil and automatic mud unloading technology, then pass the mixture of filter cake and attached liquid into the filter cake tank, and then use the filter cake pump to pump the mixture of filter cake and attached liquid into the mixing tank of a red mud washing and settling tank, and the ore pulp mixed in the mixing tank flows into the red mud washing and settling tank by itself for washing and sedimentation. Since the filter cake unloading of the vertical leaf filter adopts the recoil and automatic mud unloading technology of the filtered semen (caustic alkali concentration: 165g / l), this part of the high-...

AI Technical Summary

Problems solved by technology

Since the filter cake unloading of the vertical leaf filter adopts the recoil and automatic mud unloading technology of the filtered semen (caustic alkali concentration: 165g / l), this part of the high-concentration slurry enters the first red mud washing and settling tank, which is bound to Increased Na in the overflow of a red mud washing settling tank 2 The concentration of O also affects the sedimentation and separation effect of red mud in the primary washing sedimentation tank

The red mud settling performance of the first red mud washing settling tank is deteriorated, and the subsequent second, third, and fourth red mud washings are also negatively affected, resulting in a high loss of attached liquid in the last red mud washing

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