According to the mechanism of sulfur removal easily through oxidation, the process of smelting oxidation desulfurization of copper slags is studied, which supplies a new thinking for obtaining the molten iron of lower...According to the mechanism of sulfur removal easily through oxidation, the process of smelting oxidation desulfurization of copper slags is studied, which supplies a new thinking for obtaining the molten iron of lower sulfur content by smelting reduction of copper slags. Special attention is given to the effects of the holding temperature, the holding time and CaF2, CaO addition amounts on the desulfurization rate of copper slags. The results indicate that the rate of copper slags smelting oxidation desulfurization depends on the matte mass transfer rate through the slag phase. After the oxidation treatment, sulfur of copper slags can be removed as SO2 efficiently. Amount of Ca2＋ of copper slags affects the desulfurization rate greatly, and the slag desulfurization rate is reduced by adding a certain amount of CaF2 and CaO. Compared with CaF2, CaO is negative to slags sulfur removal with equal Ca2＋ addition. Under the air flow of 0.3 U/min, the sulfur content of copper slags can be reduced to 0. 004 67% in the condition of the holding time of 3 min and the holding temperature of 1 500 ℃. The sulfur content of molten iron is reduced to 0. 000 8 % in the smelting reduction of treated slags, and the problem of high sulfur content of molten iron obtained by smelting reduction with copper slag has been successively solved.展开更多
The characteristics And mechanism of the reduction and smelting-separation process of the copper slag were studied by investigating the variation ：rule of metallization ratio, yield as well as carbon content of iron ...The characteristics And mechanism of the reduction and smelting-separation process of the copper slag were studied by investigating the variation ：rule of metallization ratio, yield as well as carbon content of iron nuggets. The formation of molten slag is necessary for slag-iron separation, And iron is in half-molten state during smelting-separa- tion process, the carbon content of which is about 1.25 %. Carburization occurs through direct contact between car- bon and iron in essence, no matter in solid or molten state. The carburization rate is slow below 1 200 ℃ , which is inhibited by the existence of slag. Residual FeO in molten slag tends to form fayalite with SiOz in the copper slag, which is the root cause for the low mehing temperature of copper slag. The addition of CaO improves the reducibility of the copper slag, but Al2 O3 addition has no obvious effect. The melting temperature of slag affects the carburiza- tion extent in solid state, while the content of FeO in molten slag affects that in molten state, both of which co-de termine the carbon content in iron nuggets.展开更多
基金Sponsored by National Natural Science Foundation of China ( 50906035 , 51204082 )
文摘According to the mechanism of sulfur removal easily through oxidation, the process of smelting oxidation desulfurization of copper slags is studied, which supplies a new thinking for obtaining the molten iron of lower sulfur content by smelting reduction of copper slags. Special attention is given to the effects of the holding temperature, the holding time and CaF2, CaO addition amounts on the desulfurization rate of copper slags. The results indicate that the rate of copper slags smelting oxidation desulfurization depends on the matte mass transfer rate through the slag phase. After the oxidation treatment, sulfur of copper slags can be removed as SO2 efficiently. Amount of Ca2＋ of copper slags affects the desulfurization rate greatly, and the slag desulfurization rate is reduced by adding a certain amount of CaF2 and CaO. Compared with CaF2, CaO is negative to slags sulfur removal with equal Ca2＋ addition. Under the air flow of 0.3 U/min, the sulfur content of copper slags can be reduced to 0. 004 67% in the condition of the holding time of 3 min and the holding temperature of 1 500 ℃. The sulfur content of molten iron is reduced to 0. 000 8 % in the smelting reduction of treated slags, and the problem of high sulfur content of molten iron obtained by smelting reduction with copper slag has been successively solved.
基金Sponsored by National Science and Technology Support Program for 11th Five-year Plan of China(2009BAB45B05)
文摘The characteristics And mechanism of the reduction and smelting-separation process of the copper slag were studied by investigating the variation ：rule of metallization ratio, yield as well as carbon content of iron nuggets. The formation of molten slag is necessary for slag-iron separation, And iron is in half-molten state during smelting-separa- tion process, the carbon content of which is about 1.25 %. Carburization occurs through direct contact between car- bon and iron in essence, no matter in solid or molten state. The carburization rate is slow below 1 200 ℃ , which is inhibited by the existence of slag. Residual FeO in molten slag tends to form fayalite with SiOz in the copper slag, which is the root cause for the low mehing temperature of copper slag. The addition of CaO improves the reducibility of the copper slag, but Al2 O3 addition has no obvious effect. The melting temperature of slag affects the carburiza- tion extent in solid state, while the content of FeO in molten slag affects that in molten state, both of which co-de termine the carbon content in iron nuggets.
