The work addresses the issue of selecting a solidifying mixture when mining deposits of naturally lean iron ores by open stoping systems to decrease mining costs without the concern for surface subsidence. Magnetite quartzites are mined by systems applied to mining naturally rich iron ores that provide for leaving significant reserves in pillars. In view of the above, when mining magnetite quartzites, it is reasonable to consider application of open stoping with backfilling. Application of polymer additives in the backfill instead of cement allows decreasing costs for water and binders while retaining its strength. As they are able to couple with any binders and fillers, polymers can be added to not only concretes and cement grouts. This provides opportunities to widely use mining and concentrating wastes, i.e. slag and waste rock. Advantages of applying mixtures with plasticizers are: lower labour costs, reduced risks of cracking, increased abrasion resistance, lower shrinkage, increased resistance to temperature fluctuations, backfilling without vibrations, a longer concrete mixture lifecycle. Aggregate technical and economic indicators demonstrate that with similar physical properties of the backfill, polymer-based backfilling is 2-3 times cheaper as compared with the cement-based one. Thus, when stoping with backfilling at Artem underground mine, it is advisable to use a polymer blast furnace slag backfill as a solidifying mixture.
Geological Controls on High-Grade Iron Ores from Kiriburu-Meghahatuburu Iron Ore Deposit, Singhbhum-Orissa Craton, Eastern India