China Nonferrous Metallurgy

In this paper, electric arc furnace dust (EAFD), reductant and slag-forming agent were proportioned into carbon-containing pellets and added to the iron bath at 1500℃ in the vertical tube furnace to recover zinc and iron by the iron-bath smelting reduction process. The EAFD and reduced iron slag were subjected to XRF, XRD, SEM-EDS analysis and chemical analysis, and the effects of binary alkalinity R, reduction time and carbon content on dezincification and reductive melting were studied. The results showed that the maximum content of ZnO in the reduced slag was 0.24 wt%, the minimum was 0.07wt%, and the dezincification rate exceeded 99%; when R=1.6, C/O molar ratio was 1.1, and reduction duration was 40min, a majority of the zinc oxides in EAFD were reduced to Zn metal and evaporated into the off-gas, while most of the iron oxides were reduced to metallic iron and entered the iron bath after carburization and the other oxides formed molten slag and built up on the surface of the iron bath after being separated from the molten iron; the increase of the carbon content was conducive to carburization and promoted the slag-iron melting and separation, but hindered the slag-iron separation as the the excess carbon would accumulate in the molten slag when the carbon content exceeds the demand (nC/nO=1.2) for carburization.