A Novel Solution to Avoid Mercury Emissions Produced by Highly Contaminated Demolition Debris in Mining Site

Abstract

Mercury (Hg) emissions into the air can in some cases be a critical problem for public health and environmental protection. Hence, it is crucial to find cost-effective solutions to tackle this issue. An innovative solution is presented in this study using two case studies, diminishing drastically the emissions through covering high Hg-contaminated debris with industrial subproducts (fly-ashes and blast furnace slags). This solution is compared with other two conventional alternatives: (1) removal of the debris to an authorized landfill and (2) in situ encapsulation. The analysis is carried out by comparing costs, carbon footprint and the Environmental–Social–Governance (ESG) impact. It has been noted that the solution proposed has some advantages with respect to conventional alternatives, from both economic and environmental points of view, presenting lower costs and a lower carbon footprint. The worst solution is to remove the debris for ex situ treatment, while the encapsulation represents a middle solution with advantages and disadvantages. The findings of the study can be a step forward in the usage of industrial subproducts, that are currently placed in waste disposal, to solve the problem of sites contaminated by mercury and eliminate its emissions.