METHOD FOR INTEGRATED PROCESSING OF ASH FROM COAL COMBUSTION Russian patent published in 2025 - IPC C22B7/02 C22B3/08 C01F7/74 C01F17/00 C22B59/00 B09B3/00 

FIELD: performing operations.

SUBSTANCE: invention relates to complex processing of ash from coal combustion to obtain concentrate of rare and rare-earth elements, aluminium sulphate for production of coagulant, high-silica raw material for production of refractory materials and cement. Method involves removal of iron by magnetic separation, placing ash into a reaction zone, adding a sorbent to it, which provides absorption of rare elements. Obtained mixture is leached with an aqueous solution of sulphuric acid with concentration of 269 g/l at temperature of 65-70°C for 3-5 hours. Then one performs heating and holding. Sorbent is directed to production of concentrate of rare elements. Insoluble residue is filtered, mixed with concentrated sulphuric acid and heated at temperature of 300-350°C for 60-80 minutes to obtain sinter. Obtained sinter is leached with an ash leaching solution to obtain aqueous aluminium sulphate, which is used to obtain a coagulant, and a solid residue containing quartz and mullite, which is used to produce refractory materials and cement.

EFFECT: complex processing of ash from coal combustion is ensured using readily available reagent – sulphuric acid.

3 cl, 5 tbl