High Strength Iron Oxide Pellets by Polymer Impregnation.
Proc 12th Biennal Conf Inst for Briquetting and Aggl 1971 Aug; 12:125-144
A laboratory research program was initiated to determine the technical feasibility of utilizing organic polymers as binding materials for iron oxide pellets. Predried magnetite and hematite pellets impregnated with low-viscosity vinyl liquid monomers and polymerized in situ by thermal-catalytic techniques yielded compressive strengths equivalent to those reported by high- temperature induration plants. One-half-inch-diameter magnetite pellets containing less than 5 wt-pct poly(methyl methacrylate) gave compressive strengths in excess of 500 lb after polymerization at 80 deg c (176 deg f) and annealing at 200 deg c (392 deg f). Somewhat lower pellet strengths were obtained with methyl methacrylate- styrene and styrene-acrylonitrile copolymers. Polymer impregnation of both heat-hardened and cement-bonded pellets resulted in exceptionally high compressive strengths. The compressive strength of partially oxidized magnetite pellets (500 deg c (932 deg f) increased from about 100 lb to over 1,000 lb after impregnation with less than 5 wt-pct poly(methyl methacrylate). Similar strength increases were obtained after impregnation of green magnetite pellets containing from 2.5 to 5.0 pct portland cement binder.
Proc. 12th Biennal Conf. Inst. for Briquetting and Aggl., V. 12, August 1971, PP. 125-144