METHOD OF DECOMPOSING ALUMINATE SOLUTIONS WHEN PROCESSING NEPHELINE RAW MATERIAL Russian patent published in 2016 - IPC C01F7/14 C22B3/04 

FIELD: chemistry.

SUBSTANCE: invention relates to chemistry and nonferrous metallurgy and can be used in processing of low-quality aluminium-containing material, including nephelines, by sintering. Disclosed method involves dividing solution after first desiliconisation step into a soda-alkaline and a soda branche, wherein solution in soda-alkaline branch is subjected to decomposition and carbonisation, and in soda branch solution after deep desiliconisation is subjected to carbonisation. According to invention, decomposition of aluminate solution in soda-alkaline and soda branches is performed by decomposition, followed by carbonisation of solutions of gases containing CO₂, providing low concentration of caustic alkali in solution at a rate of 10 g/l·h until achieving concentration of carbonate alkali and degree of decomposition of aluminate solution.

EFFECT: technical result is increase of average particle diameter of production of aluminium hydroxide and reduced output of a fraction smaller than 45 mcm during complex processing of nepheline concentrate, as well as formation of mechanically stable structure of deposit, preventing increased milling of particles of alumina in calcination process.

1 cl, 1 dwg, 12 ex