In order to further understand the debismuthizing mechanism with calcium and magnesium, the influence of adding amount of calcium on the bismuth removal from lead was examined. A part of the debismuthizing dross sampl...In order to further understand the debismuthizing mechanism with calcium and magnesium, the influence of adding amount of calcium on the bismuth removal from lead was examined. A part of the debismuthizing dross samples were studied by electron probe microanalysis （EPMA）. The results show that the calculated bismuthide governing debismuthizing process is Ca3Mg7Bi8, which may be a mixture of Ca3Bi2, CaBi, CaBi3 and Mg3Bi2. And the bismuthide formed during the debismuthizing process exists in two states： one is free bismuthide in the matrix of dross, and the other is symbiotic with Pb-Ca phase.展开更多
In order to achieve fine debismuthizing of lead bullion,the effects of temperature,adding amount of calcium and magnesium and antimony on the bismuth removal from lead bullion were investigated.The mechanism of debism...In order to achieve fine debismuthizing of lead bullion,the effects of temperature,adding amount of calcium and magnesium and antimony on the bismuth removal from lead bullion were investigated.The mechanism of debismuthizing was also discussed.The results show that when adding amounts of calcium and magnesium reach 0.112% and 0.395%,respectively,bismuth level of 0.001%（mass fraction） in the final lead is achieved at 330 ℃,without the need for antimony addition.Maintaining addition amount of magnesium at 0.155%,when calcium addition amount is less than 0.09%,the concentration of peritectic reaction point,the bismuth concentration can be easily decreased to 0.001% by the following antimony treatment.But the effect of antimony treatment on debismuthizing gets bad if the calcium addition exceeds 0.09%.展开更多
文摘In order to further understand the debismuthizing mechanism with calcium and magnesium, the influence of adding amount of calcium on the bismuth removal from lead was examined. A part of the debismuthizing dross samples were studied by electron probe microanalysis （EPMA）. The results show that the calculated bismuthide governing debismuthizing process is Ca3Mg7Bi8, which may be a mixture of Ca3Bi2, CaBi, CaBi3 and Mg3Bi2. And the bismuthide formed during the debismuthizing process exists in two states： one is free bismuthide in the matrix of dross, and the other is symbiotic with Pb-Ca phase.
文摘In order to achieve fine debismuthizing of lead bullion,the effects of temperature,adding amount of calcium and magnesium and antimony on the bismuth removal from lead bullion were investigated.The mechanism of debismuthizing was also discussed.The results show that when adding amounts of calcium and magnesium reach 0.112% and 0.395%,respectively,bismuth level of 0.001%（mass fraction） in the final lead is achieved at 330 ℃,without the need for antimony addition.Maintaining addition amount of magnesium at 0.155%,when calcium addition amount is less than 0.09%,the concentration of peritectic reaction point,the bismuth concentration can be easily decreased to 0.001% by the following antimony treatment.But the effect of antimony treatment on debismuthizing gets bad if the calcium addition exceeds 0.09%.
