Aluminate hydrate wash liquor digestion method in manufacturing process of aluminium oxide by sintering method

Abstract

The invention relates to an aluminate hydrate wash liquor digestion method in the manufacturing process of an aluminium oxide by a sintering method, which is characterized in that the method comprises the following steps: the aluminate hydrate wash liquor is evaporated and concentrated, and then enters a seed separation evaporator for evaporation, and serves as ingredients with seed separation mother liquor in the desilication process. In the method, the aluminate hydrate wash liquor in the sintering method drops out of the clinker digestion correction liquor, is directly sent to the evaporator for evaporation after being sprayed, evaporated and concentrated in a clinker kiln cooler, and is used as the seed separation liquor, thus optimizing the digestion, separation and washing techniques of the sintering method, truly realizing the technique requirement of low caustic ratio digestion, reducing the occurrence of secondary reaction of the system, being advantageous for the stability of slurry index and the high-yield and steady operation of the clinker kiln, being capable of decreasing the crude liquor ak value by 0.02 under the condition of unchanged clinker [N / R], improving the net digestion rate of the aluminium oxide by as high as 0.5%, solving the problem of the destination of aluminate hydrate wash liquor fundamentally.

Description

technical field [0001] The invention relates to a method for digesting aluminum hydroxide lotion in the production process of sintered alumina. Background technique [0002] In the process of producing alumina by sintering method, the clinker after being fired in the clinker kiln is dissolved and the red mud is separated and washed. The sodium aluminate solution produced in this process is called crude liquid in the production, and the crude liquid is further removed. Silicon is decomposed after refining, and the sodium aluminate solution is decomposed to produce aluminum hydroxide slurry, which is separated and washed, and then reaches the final process. The lotion produced during the washing process of aluminum hydroxide is the aluminum hydroxide lotion, commonly known as white washing. [0003] Aluminum hydroxide washing liquid has been used as one of the adjusting liquid components for clinker dissolution in the process of producing alumina by sintering method. Its aK v...

AI Technical Summary

Problems solved by technology

If the amount of aluminum hydroxide washing solution consumed for clinker dissolution changes significantly, it will lead to inconsistencies between the crude liquid aK and the clinker [N / R]. In the case of high crude liquid aK, red mud The secondary reaction of the separation and washing system will increase significantly, the condition of the separation tank will deteriorate, the net dissolution of alumina will be reduced, and the amount of silicon slag will increase, which will affect the stability of the raw slurry

And it is forced to adjust the raw clinker [N / R] formula in the incoming materials of the previous process, which is not conducive to the stable operation of the clinker kiln