A method for adjusting carbon-alkali material balance in alumina production process

Abstract

The invention relates to a method for recycling carbon and alkali systematically during production of aluminum oxide, in particular to a method for adjusting balance of carbon-alkali materials in a production technology of the aluminum oxide. The method is characterized by sequentially including the steps that 1, CO2 gas is injected into sintering method carbonated mother liquor, in this way, caustic alkali in the sintering method carbonated mother liquor completely reacts with CO2, CO2 gas is injected into a solution, and then the aluminum oxide is sufficiently separated out; 2, slurry which the CO2 gas is injected into is filtered one time, filtrate stands and is cooled, and remaining aluminum oxide in the filtrate and other metal ions are further separated out and precipitate; secondary filtering is carried out, the pH value of secondary filtrate is determined, and chemical components of the solution are analyzed; 4, sodium hydroxide or solid sodium hydroxide is added into the secondary filtrate to obtain the pH value of the solution through blending so that requirements for alkaline water used for ore dressing can be met; 5, after the pH value is qualified through blending, the secondary filtrate is delivered to a floatation process of an ore dressing Bayer method.

Description

technical field [0001] A method for adjusting the material balance of carbon and alkali in an alumina production process relates to a method for recycling carbon and alkali in a system in the alumina production process. Background technique [0002] The carbon alkali in the sintering production system mainly comes from the carbon separation mother liquor. At present, the circulation route is that a part of the clinker is dissolved, and a part is returned to the ingredients after evaporation. The carbonation decomposition process will produce a large amount of carbon separation mother liquor. Usually, the above two methods cannot effectively solve the problem of carbon mother recycling, which directly restricts the improvement of the carbonation decomposition capacity of the sintering method. [0003] In the beneficiation Bayer process system, the presence of a large amount of carbon and alkali is not conducive to production, especially it will reduce the decomposition rate ...

AI Technical Summary

Problems solved by technology

The carbonation decomposition process will produce a large amount of carbon mother liquor. Usually, the above two methods cannot effectively solve the problem of carbon mother recycling, which directly restricts the improvement of the carbonation decomposition production capacity of the sintering method.

[0003] In the Bayer process system of beneficiation, a large amount of carbon soda is not conducive to production, especially it will reduce the decomposition rate of seeds. Therefore, in the evaporation and salt removal process, the carbon soda and a small amount of other sodium salts in the process will leave the system in the form of salt discharge filter cake. This part of carbon soda has not yet found an effective way to recycle it