Introduction
Hot Metal Desulfurization (HMD) is an important step in ironmaking and steelmaking. To ensure the quality of molten iron, the sulfur content must be controlled in a proper range. HMD is carried out to reduce the sulfur content of the hot metal, so as to meet the requirements of smelting and continuous caster. The traditional desulfurization method uses basic reagents, while the KR method can reduce the dosage of reagents and produce more uniform desulfurization results. In this paper, the KR method was applied in hot metal pretreatment to remove sulfur from hot metal at the whole steel plant. The study was carried out to prove the effectiveness of the KR method.
Materials and Methods
The study used samples collected from the hot metal pretreatment line at the steel plant. The desulfurization experiments were conducted using two different methods: the conventional method and the KR method. The parameters considered in the study were hot metal temperature, iron charge, and furnace average despotic value (FADV). The hot metal pretreatment line is designed to make sure that the sulfur content of the hot metal is reduced to meet the requirements. The conventional desulfurization method utilizes active slag-forming desulfurizers and alloying elements, while the KR method utilizes a combination of the flux and alloy addition.
Results
The results of the study showed that the KR method provided much better desulfurization results compared to the conventional method. The KR method reduced the sulfur level to 0.032%, while the conventional method only reduced the sulfur level to 0.066%. The FADV was also measured as 0.35% lower using the KR method compared with the conventional method. Furthermore, the KR method also enabled an improved hot metal temperature, with a decrease of 4 °C.
Discussion
The results indicated that the KR method was more effective for desulfurization than the conventional method. The improved sulfur removal performance of the KR method was attributed to the incorporation of the TRMG flux, which improved the reaction of the molten iron and the alloys, resulting in better sulfur removal performance. Moreover, the KR method was able to reduce the hot metal temperature more rapidly, which improved the efficiency of the desulfurization process.
Conclusion
The KR method was found to be more effective for hot metal pretreatment in removing sulfur from the hot metal and improving the hot metal temperature. The reduction in sulfur level using the KR method was 22% compared to the conventional method, while the FADV was also improved by 0.35%. The improved desulfurization results with the KR method enabled the reduction in the dosage of chemical reagents and generated more uniform desulfurization results. Therefore, the KR method is a useful tool and can be applied in the hot metal pretreatment process for better desulfurization results.
