Recycling sterile gold mining waste for use as construction aggregate

Abstract

Gold is found in part by the thousands in rocks, which makes it necessary to mine a large quantity of rock in order to obtain a minimum quantity of gold. This leads to the generation of a significant amount of solid waste product because of the crushing and grinding of the material that generates waste from block size to sandy and fine granulometry. These residues end up as deposits on the surface or slopes that generate the danger of landslides or damage in the soil, another large part of the ground material ends up dumped in rivers and streams, which increases the rate of sedimentation and the deposition of heavy metals. In Colombia, the areas that are dedicated to the exploitation of gold encompass large regions, which generates that a significant amount of water sources are affected, in addition, the mines are in some cases close to the paramos such as the Santurban paramo, an important source of water in the north of Colombia. In the field studies, it was observed that 6 tons of sterile waste is generated per day that meets the standards as a construction aggregate for use in the concrete mix. In the tests carried out it was found that it can be used for structural concrete. Petrographic and chemical analyzes revealed significant silica content from plagioclase, quartz, and micas that make up the sterile residue. KeywordWaste Minimization, Aggregate Concrete, Sustainability, mining, gold