The iron and steel industry is facing a strong demand to improve the quality and variety of steel, and the sulfur content in steel affects this result. Sulfur has a bad influence on the properties of steel; Sulfur reduces the plasticity and toughness of steel and affects the surface quality and internal integrity of steel. Therefore, the days when the minimum sulfur content in steel was required to be .35% are gone forever. At present, the average sulfur content in steel is required to be within the range of ≤.15% for most applications. In some steels, such as pipeline steel, the sulfur limit even reaches the level of .2-.5%. However, the traditional production process of blast furnace-oxygen top-blown converter is helpless for sulfur to meet the above requirements. From October, 1998 to January, 1999, the research group conducted an industrial test of desulfurization of 3t molten iron with magnesium base outside the furnace in Tianjin Steel Plant. The * * * treated 51t molten iron and consumed 25kg magnesium, which reduced the sulfur content of molten iron in cupola from about .75% to below .25%. The 24 yuan /t-iron cost of magnesium-based hot metal desulfurization process outside the furnace is good, creating a small tonnage (<: 3t), shallow solution tank (<: 1.4m) is the first example of desulphurization of magnesium-based hot metal outside the furnace. Magnesium-based desulfurizer has the advantages of low temperature of molten iron, high desulfurization efficiency and low consumption. The treatment time of molten iron is 5-1min and the temperature drop is within 2℃. Magnesium-based desulfurizer has the advantages of low temperature of molten iron, high desulfurization efficiency and low consumption. The treatment time of molten iron is 5-1min, and the temperature drop is within 2℃. Magnesium-based desulfurizer is mainly added by blowing, and nitrogen is used as carrier gas, which is easy to operate. The injection system is designed and assembled by University of Science and Technology Beijing. The injection system includes a quantitative feeding device, an ejector, a gas distribution bag, a control instrument, a conveying pipeline and a spray gun. In addition, other methods of adding magnesium to treat molten iron were carried out in the laboratory, and the methods of desulfurization of molten iron outside cupola, induction furnace and small blast furnace were basically mastered, which made the desulfurization of magnesium-based molten iron furnace in China catch up with the advanced level in the world. At the same time, it fills the blank of pretreatment of molten iron in shallow molten pool with magnesium-based desulfurization, and is in a leading position. On November 2, 1999, the technology applied to the State Patent Office for a patent (99122343x). This technology has been taken as the key promotion project of the scientific research department and development corporation of the school. On March 16th, 1999, the World Metal Herald made a public report.
characteristics of hot metal desulfurizer and application of magnesium-based desulfurizer in baotou steel co
common desulfurizers during hot metal pretreatment and application.