| CPC C01G 49/009 (2013.01) [C01B 25/26 (2013.01); H01M 4/58 (2013.01); H01M 10/052 (2013.01); C01P 2004/64 (2013.01); C01P 2006/40 (2013.01)] | 8 Claims |
|
1. A preparation method of a manganese iron phosphate precursor, characterized in that the manganese iron phosphate precursor is prepared based on a high-temperature calcination device, wherein the high-temperature calcination device comprises a first dissolution tank, a second dissolution tank, a mixing tank, a Venturi processor, a pump, a valve, and a vertical high-temperature roasting furnace, wherein the high-temperature roasting furnace comprises a sprayer located at the top, at least one set of heaters, and at least one particle size regulator, wherein the heaters are arranged in the middle and at the bottom of the outer surface of the high-temperature roasting furnace, wherein the particle size regulator is arranged inside the high-temperature roasting furnace corresponding to the position of the heaters, wherein the particle size regulator is configured to make the sprayed droplets move in reverse to adjust the suspension time of the droplets to control the particle size of the manganese iron phosphate precursor, wherein an outlet of the first dissolution tank and an outlet of the second dissolution tank are connected to a first inlet of the mixing tank, wherein an outlet at the bottom of the mixing tank is connected to a first inlet on a side wall of the Venturi processor, wherein an outlet at the bottom of the Venturi processor is connected to an inlet of the pump, wherein an outlet of the pump is connected to an inlet at the top of the high-temperature roasting furnace and a second inlet on the side wall of the Venturi processor, respectively, wherein a first outlet near the top of the high-temperature roasting furnace is connected to a third inlet at the top of the Venturi processor;
wherein any of the particle size regulators comprises a spiral gas pipe, wherein a plurality of jet holes are arranged on one side of the spiral gas pipe close to the sprayer, and the diameters of the jet holes in each semicircle of the spiral gas pipe increase successively from the inside to the outside along the spiral gas pipe, and the jet holes of the spiral gas pipe are distributed at preset angles in a clockwise or counterclockwise direction, or the jet holes of adjacent loops of the spiral gas pipe are arranged in a staggered manner;
wherein the preparation method comprises:
S11. reacting the manganese source with hydrochloric acid in the first dissolution tank to generate a manganese-containing solution;
S12. reacting the iron source, phosphorus source, and hydrochloric acid in the second dissolution tank to generate an iron phosphate solution;
S2. uniformly mixing the manganese-containing solution, the iron phosphate solution, and dispersant in the mixing tank to obtain a mixed solution;
S3. transporting the mixed solution through the pump from the mixing tank to the Venturi processor for preheating;
S4. transporting the preheated and concentrated mixed solution through the pump to the inlet of the high-temperature calcination furnace;
S5. spraying and roasting the mixed solution in the high-temperature calcination furnace in the atmosphere of the carrier gas, forming a powdered manganese iron phosphate precursor with at least two preset particle sizes through the sprayer and the particle size regulator;
S6. water washing and grinding, demagnetizing, and drying the manganese iron phosphate precursor with at least two preset particle sizes to obtain the manganese iron phosphate precursor with at least two preset particle sizes.
|