Bauxite desulphurization method and device

[0033] Example 1

[0034] Taking a high-sulfur bauxite ore under coal in a certain area of ​​Henan Province as the test ore sample, the chemical composition of the ore is shown in Table 1.

[0035] Table 1 High-sulfur bauxite mine under coal in a certain area in Henan

[0036] ingredient Al 2 O 3 SiO 2 Fe 2 O 3 TiO 2 K 2 O Na 2 O CaO MgO S C Discretionary content/% 63.46 12.35 2.64 2.96 1.10 0.025 0.81 0.25 1.21 1.80 13.40

[0037] The test process consists of a section of rapid chemical desulfurization underflow in parallel with two of the equipments for bioleaching desulfurization.

[0038] Process parameters: rapid chemical desulfurization grinding fineness of 78%-200 mesh, natural pulp pH value, chemical desulfurization agent dosage 400g/t, desulfurization temperature is normal temperature; chemical desulfurization underflow enters the second stage mill through the discharge port to the grinding The fineness is 92% -200 mesh. After entering the stirring channel, inoculate Thiobacillus ferrooxidans, adjust the pH of the slurry to 2.5, and use a pump to deliver to two parallel devices for bioleaching desulfurization.

[0039] Test equipment:

[0040] Device for rapid chemical desulfurization: the inner diameter of the tank body is 1.5m, the tank body material is steel, the inner wall is coated with an acid-proof layer, the total height of the tank body is 4.1m, the height ratio of the column and the cone is 1.5:1, overflow The connection line between the highest point and the lowest point of the bottom of the tank is 10° to the horizontal plane. The inlet is fed from the side of the tank body. The slurry nozzle has an inner diameter of 18mm and the number of nozzles is 3, evenly distributed on the circumference. Gas distributor It is distributed in a ring-net shape and is 30mm higher than the inside of the cone. The gas distributor ring-net pipe has air inlet holes every 50mm. The single tank has rapid chemical desulfurization. The inlet pressure is 0.15MPa and the inflation pressure is 0.3MPa.

[0041] Two devices for biological leaching and desulfurization: the inner diameter of the tank body is 4.5m, the tank body material is steel, the inner wall is coated with an acid-proof layer, the total height of the tank body is 7.5m, and the height ratio of the column to the cone is 3:1. The connection line between the highest point and the lowest point of the bottom of the overflow tank is 10° to the horizontal. The inlet is fed from the side of the tank body. The slurry nozzle has an inner diameter of 16mm and the number of nozzles is 6, evenly distributed on the circumference. The distributor is distributed in a ring net shape 50mm higher than the inside of the cone. The gas distributor ring net pipe has air inlet holes every 100mm, the inlet pressure is 0.10MPa, and the inflation pressure is 0.15MPa. After biological leaching desulfurization, the bauxite is filtered and washed to become low-sulfur bauxite. A part of the filtrate is returned as the leaching bacterial seed liquid, and the other part is mixed with the washing liquid after the sulfate radical is extracted and neutralized into neutral water. Neutral water is returned for ore grinding, chemical desulfurization and washing of ore after biological leaching.

[0042] The 1.5m inner diameter single tank is continuously operated for rapid chemical desulfurization, and the 4.5m inner diameter bioleaching desulfurization device corresponding to the underflow is switched every 24 hours to ensure that the single tank bioleaching time is 24h. Continuous operation for 168h, the average process index is shown in Table 2.

[0043] Table 2 Desulfurization test results of high-sulfur bauxite in a coal mine in Henan

[0044] Product Yield/% S grade/% Raw ore 100.00 1.21 Fast chemical desulfurization underflow 96.51 0.46 Low-sulfur aluminum concentrate 96.02 0.25

[0045] Example 2

[0046] Taking a high-sulfur bauxite ore in Zunyi as the test ore sample, the chemical composition of the ore is shown in Table 3.

[0047] Table 3 High-sulfur bauxite mine in Zunyi

[0048] ingredient Al 2 O 3 SiO 2 Fe 2 O 3 TiO 2 K 2 O Na 2 O CaO MgO S Discretionary content/% 65.61 7.97 6.19 2.88 1.22 0.04 0.13 0.14 1.63 13.79

[0049] The test process consists of a section of rapid chemical desulfurization underflow in parallel with four of the equipments for bioleaching desulfurization.

[0050] Process parameters: rapid chemical desulfurization grinding with a fineness of 65%-200 mesh, natural pulp pH value, chemical desulfurization agent dosage 300g/t, desulfurization temperature at room temperature; chemical desulfurization underflow enters the second-stage mill through the discharge port to the grinding The fineness is 90% -200 mesh. After entering the stirring channel, inoculate Thiobacillus ferrooxidans, adjust the pH value of the slurry to 2.0, and use a pump to transfer to the 4 parallel devices for biological leaching and desulfurization.

[0051] Test equipment:

[0052] Device for rapid chemical desulfurization: the internal diameter of the tank body is 0.5m, the tank body material is plexiglass, the total height of the tank body is 1.5m, the height ratio of the column and the cone is 2:1, and the bottom of the overflow tank is the highest point The line with the lowest point is 15° to the horizontal plane. The feed inlet is fed from the side of the tank body. The slurry nozzle has an inner diameter of 12mm and the number of nozzles is 3, evenly distributed on the circumference. The gas distributor is distributed in a ring network. 15mm higher than the inside of the cone, the gas distributor ring network pipe has air inlet holes every 30mm, single tank rapid chemical desulfurization, the inlet pressure is 0.10MPa, and the inflation pressure is 0.2MPa.

[0053] Four devices for biological leaching desulfurization: the internal diameter of the tank body is 1.5m, the tank body material is steel, the inner wall is coated with an acid-proof layer, the total height of the tank body is 4.1m, and the height ratio of the column and cone is 1.5:1. The connection line between the highest point and the lowest point of the bottom of the overflow tank is 10° to the horizontal plane. The inlet is fed from the side of the tank body. The slurry nozzle has an inner diameter of 18mm and the number of nozzles is 3, evenly distributed on the circumference. The distributor is distributed in a ring net shape 30mm higher than the inside of the cone. The gas distributor ring net pipe has air inlet holes every 50mm. The inlet pressure is 0.08MPa and the inflation pressure is 0.10MPa. After biological leaching desulfurization, the bauxite is filtered and washed to become low-sulfur bauxite. A part of the filtrate is returned as the leaching bacterial seed liquid, and the other part is mixed with the washing liquid after the sulfate radical is extracted and neutralized into neutral water. Neutral water is returned for ore grinding, chemical desulfurization and washing of ore after biological leaching.

[0054] The 0.5m inner diameter single tank is continuously operated for rapid chemical desulfurization, and the 1.5m inner diameter bioleaching desulfurization device corresponding to the underflow is switched every 24 hours to ensure that the single tank bioleaching time is 48h. Continuous operation for 168h, the average process index is shown in Table 4.

[0055] Table 4 Desulfurization test results of a high-sulfur bauxite mine in Zunyi

[0056] Product Yield/% S grade/% Raw ore 100.00 1.63 Fast chemical desulfurization underflow 97.26 0.35 Low-sulfur aluminum concentrate 96.89 0.21