| A study on the effect of Pb and Cu in zinc ore is executed for a preventive measures of the fluidized bed agglomeration during the roasting of zinc concentrate. The more the contents of Pb and Cu in zinc concentrate increase, the more the amount of agglomeration increases. Especially, when the contents of Cu in zinc concentrate is over 2.5wt%, the roasting process is very hard. The more the roasting temperature increase, the more the amount cf agglomeration increases during the roasting of the concentrate (Pb 1.5%, Cu 0.7%), and the sorts of compound in agglomerating calcine get to be different. Namely, at 850-950℃, the agglomerating calcine contains ZnO, ZnO·Fe₂O₃,CuSO₄, 2PbO·PbSO₄4PbO·PbSO₄and 2PbO·SiO₂, etc.. At 800℃, 4PbO·PbSO₄is not contained, but at 750℃, ZnO, ZnO·Fe₂O₃, CuSO₄and PbSO₄are contained. When air blowing increases, the agglomeration decreases. In the effect for the change of particle size, when the size decreases, wt.% of bed agglomerating calcine decreases. In these experimental results for the preventive measures of the fluidized bed agglomeration, Pb and Cu in zinc concentrate must decrease less than 0.5%, 0.2% respectively, and air blowing must occasionally increase. |
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