Crude pellets for reduction in rotary furnace - produced from dust contg. iron mixed with carbon source and bentonite

摘要

dust (I) is mixed with a C-source (II) consisting of coke and/or coal comminuted to fine particles and contg. a large quantity of C having low volatility. Ratio of C no. in (I) + (II) mixt. to no. of 0-atoms bonded to Fe in (I) + (II) mixt. is 0.75-1.25. Mixt. (I) + (II) is mixed with 0.5-7 (0.8-3) wt. % (w.r.t. mixt.) of bentonite. Resulting mixt. is pelletised to form pellets having porosity 27-40%. Pellets are dried at a temp. such that C in pellets is not burned, pref. at 300 degrees C. Crude pellets can easily be reduced to metallised pellets having a high Fe content. Bentonite content and porosity 27% prevent the breaking of pellets on quick heating to 400 degrees C. Bentonite improves compressive strength of pellets.