carbonaceous material with iron ore during agglomeration has definite advantages. The reduction kinetics is expected There is a need for the development of efficient to be enhanced owing to the presence of reductants in situ, industrial processes to use iron ore fines of high leading to shorter diffusion distances of the reductant, and grade. Attention is particularly drawn to rotary kiln also because a large number of reaction sites are available sponge ironmaking technology using lump iron ore, simultaneously. These agglomerates must be cold bonded where productivity is low and energy consumption since the carbonaceous material is to be retained for reduction. high compared with gas based processes.Any attempt to heat harden would result in premature Fundamental studies carried out elsewhere indicate consumption of in situ reductants. that the reduction of lump iron is accelerated if aThe reduction of iron oxides mixed with carbonaceous limited amount of carbonaceous material is material has been an interesting area of research for many incorporated in the agglomerate of iron ore fines.years. Most investigations have been of a fundamental Based on these considerations, cold bonded nature, studying the kinetics and reaction mechanisms of ore-coal composite pellets have been developed carbothermic reduction.3-8 These studies have been confor sponge ironmaking in a rotary kiln. These ducted on either single particles or handmade agglomerates. composite pellets were tested in the laboratory andIn a few cases, a commercial process has been developed to found to reduce very quickly, compared with lump produce ore-coal agglomerates, with subsequent reduction iron ore. Composite pellets were also tested in an studies. In a programme started at Michigan Technological 8 t/day rotary kiln sponge iron plant giving University (MTU) in 1966, a cold bonded pelletisation enhanced productivity and lower coal consumption, process termed 'MTU Pelletech' was developed,1 but low and these results will be presented in Part 2 of this temperature, high pressure autoclaving was needed to paper (next issue).I&S/1494a harden the green pellets. Another process termed 'Inmetco' produced green pellets without any heat hardening step2At the time the work was carried out, Dr Agrawal and Dr Prasad but the pellets were so weak that they had to be charged were at the R&D Centre for Iron and Steel, Steel
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.