Use of gold mill tailings in making bricks: a feasibility study

摘要

This laboratory-scale study was aimed at utilizing gold mill tailings from the mill tailings dumps at Kolar Gold Fields by using them in making bricks. As the mill tailings alone were not suitable for this purpose due to their low plasticity, suitable additives such as ordinary Portland cement, black cotton soils (A and B) and red soils (C and D) were mixed with the mill tailings. The cement-tailings bricks containing 20% of cement and having 14 days of curing met the required com-rnpressive strength but the cost would be 2.4 times the traditional clay bricks. The soil-tailings bricks using soils A, B, C, and D at 65, 75, 50 and 45% of mill tailings, respectively, passed the required criteria in terms of compressive strength, linear shrinkage and water absorption. The cost of soil-tailings bricks with soils A, B, C and D would be 0.74, 0.72, 0.83 and 0.85 times, respectively, of the cost of traditional clay bricks. However, mineralogical and chemical compositions need to be evaluated for safety in brick making and utilization of the respective bricks for construction purposes.