The quality requirements of active lime

With the development of steelmaking technology, the production of active lime and the quality of iron and steel have also made great progress. The quality of Shanxi active lime used in slagging in the smelting process has also been higher. The activity of lime is to neutralize the quicklime. It is expressed by the number of milliliters of 4mol/L acid consumed by Ca(OH)2 produced during digestion.

Generally, the average activity of lime exceeds 300ml/4N-HCl, which can significantly shorten the initial slagging time of the steel-making converter, reduce the consumption of lime per ton of steel, and is extremely beneficial to the early removal of P. It is called active lime.

Application of active lime in hot metal pretreatment

In order to improve the quality of molten steel and adapt to the development of various types of steel, the lower the sulfur of the molten iron, the better. For this reason, the molten iron pretreatment desulfurization process is indispensable. Large domestic steel mills have matched hot metal pretreatment and desulfurization stations accordingly. The working principle is: Nitrogen is used as the power carrier gas, and the liquid lime (prepared from active lime) is used as the carrier to stably and uniformly transport the metal magnesium powder to the molten iron. The magnesium powder reacts with the sulfur in the molten iron to form magnesium sulfide, which is removed by slag removal . Of course, liquid lime also plays a part of desulfurization, but the final desulfurization effect of molten iron is determined by the injected magnesium powder. The role of fluid lime: as a carrier; it can control the volatilization rate of magnesium and prevent the volatilization of magnesium; participate in desulfurization, and the comprehensive desulfurization rate is greater than 60%; under the same desulfurization conditions, calcium oxide-magnesium-based desulfurization agent is better than calcium oxide-magnesium-based desulfurization The agent reduces the amount of slag by about 15%, reduces the iron loss and reduces the process investment. Therefore, calcium oxide-magnesium-based desulfurizers have been more commonly used.

Active lime

Application of active lime manufacturers in iron ore powder sintering

Production experiments show that adding active lime to sintering can strengthen the sintering process and is one of the effective measures to increase the output of sintered ore. Mainly manifested in: as the activity of adding active lime increases, the sintering speed increases, and the sintering output increases; the granulation effect of the mixture is obviously improved (the average particle size of the mixture increases); the mixture heats up faster, and the highest material temperature Increase; in the case of a certain sintering basicity, the dosage of other fluxes can be reduced, and the sinter grade can be significantly improved.

Influence of negative pressure in active lime kiln.

The moving speed of active lime material in the kiln.

Under the same heat exchange conditions, if the moving speed of active lime in the rotary kiln is too large, the time required to preheat the material will be longer, and the distance in the rotary kiln will be longer. In this case, the edge length of the active lime kiln pre-heating zone will occur, and the position of the calcining zone will move forward or become shorter.

If the negative pressure in the active lime price kiln is too large, the temperature at the end of the kiln will increase, so that the heat exchange intensity of the material at the end of the kiln will be greater, and the active lime material will heat up faster. When the preheating zone becomes shorter, the length of the active lime kiln firing zone will also increase, causing the position to shift back.