GAO Jin-tao
,
LI Shi-qi
,
ZHANG Yan-ting
,
ZHANG Yan-ling
,
CHEN Pei-yu
,
SHEN Ping
钢铁研究学报(英文版)
The process of “re-resourcing of converter slag” was put forward based on the analysis of the existing steel slag treatment process. The converter slag obtained from Jinan steel plant was studied. After grinding, the slag contained 33% of iron particles, 5484% of magnetic part (wTFe=20%), and 4184% of non-magnetic part, which could be used for making cement directly. At a temperature below 1000 ℃, the non-magnetic Fe2O3 in the slag could be efficiently reduced to magnetic iron by pure H2 and CO. The slag after precise reduction had high degree of dispersion and did not get sintered, which provided an optimum condition for the separation of iron and impurities. To separate the slag and enrich the iron after reduction, the laboratory-scale device of magnetic separation was designed and made. The process of slag re-resourcing, which included magnetic sorting, precise reduction, magnetic separation, and removal of free calcium oxide (f-CaO), was proposed to obtain iron-rich magnetic materials and cement adulterant materials. Through this process, 33 kg iron particles, 150 kg iron-rich material and 700 kg cement could be obtained in each ton slag. Besides, this process to recycle converter slag had a lower energy and material consumption and no pollutant emission.
关键词:
converter slag
,
resource recycling
,
precise reduction
,
cement
WU Long
,
PEI Fen
,
CHEN Yu
,
LI Shi-qi
钢铁研究学报(英文版)
Abstract: CaO-Al2O3-SiO2-CaF2-MgO was selected as the slag system for desulfurization in LF process. The reaction between steel and slag during desulfurization has been simulated by using Factsage software to study the influence of component on the sulfur distribution ratio. In order to research the influence of CaO content, aluminum powder content and its granularity on desulfurization, laboratory experiments have been carried out in a 200 kg inductive furnace. Results showed that the optimal composition of deep desulfurizer is wCaO=64% and aluminium powder 10% with a granularity of 30 μm. Industrial trials showed that the main composition range of final slag in LF process is wCaO=530%-570%, wAl2O3=234%-251%, wSiO2=81%-100%, and wCaF2=32%-47%. The sulfur mass percent in steel is lower than 00008% with a desulfurization rate above 89%. According to the result of industrial production, this desulfurizer could meet the production requirement for ultra-low sulfur steel, of which sulfur mass percent is under 00015%.
关键词:
Key words: refining slag
,
deep-desulfurization
,
sulfur distribution ratio
,
desulfurization rate