How can high-sulfur iron ore increase value?

In the process of steel smelting, sulfur will make the steel brittle and cause the steel to break. Therefore, during high-temperature forging and steel rolling, the sulfur content in it is required not to exceed 0.05%. This requires that the iron concentrate used in iron and steel smelting should not contain too much sulfur.

Therefore, for the separation of high-sulfur iron ore, desulfurization of iron concentrate is a key issue, and it is also one of the key factors to increase value. To this end, we have adopted the method of magnetic separation + flotation to desulfurize high-sulfur iron ore to increase the economic value of the ore.

Step 1: The high-sulfur iron ore is crushed until the ore particle size is below 2mm, and then enters the ball mill for grinding. The ore grinding fineness is controlled at 200 mesh, and the raw ore is added with water to form a slurry state.

Step 2: Carry out primary separation of the ore pulp, adopt low-intensity magnetic separation, and the magnetic field strength is 119~151kA/m, and obtain magnetite coarse concentrate and tailings.

Step 3: Carry out secondary grinding on the magnetite coarse concentrate, the degree of dissociation of the ore is further improved, and the fineness of the raw ore is further reduced.

Step 4: Perform low-intensity magnetic separation on the pulp after the secondary grinding to obtain magnetite concentrate and tailings, and the sulfur content in the iron concentrate is reduced to below 0.2%.

Step 5: Concentrate the tailings in the second and fourth steps and then carry out flotation. The flotation method is primary roughing + primary sweeping + secondary concentration. The collectors are mercapto-carboxylates and four alkali yellows or ethyl xanthate, and the amount of collector is 30-450g/t to obtain iron concentrate and tailings.

Step 6: Perform strong magnetic separation on the tailings, the number of strong magnetic separations is 2 to 3 times, and the magnetic field strength of the magnetic separation is 1.0 to 1.5T to obtain hematite concentrate and tailings.

Step 7: The tailings are dehydrated with a linear vibrating screen. After the solid concentration on the screen is greater than or equal to 85%, the solids are transported to the stockyard as building materials, and the slurry under the screen is used as real tailings to enter the mine tailings pond.