Mitigation of Environmental Hazards and Greenhouse Gas Emissions Through Use of Post-Consumer Glass as a Cementing Agent in Mine Backfill

This paper examines aspects of mine backfilling operations that may be implemented to assist in reducing solid waste production, lowering energy costs, and restricting Greenhouse Gas Emissions. Many underground mines use cemented backfill to provide ground support and to mitigate environmental effects associated with tailings disposal. In Ontario, mining operations contribute approximately 700,000 - 840,000 tonnes/year of CO₂ and Greenhouse Gas emissions to satisfy backfill cement consumption needs alone. Potential reductions of cement in backfill would significantly reduce emission of these gases and lower their adverse environmental impacts. This paper introduces post-consumer glass as an alternate, equally effective and lower cost binder agent strategy for backfill that may be implemented to assist in reducing backfill energy costs; and ultimately reducing Greenhouse Gas emissions levels generated by the mining industry. Extensive engineering testing, consisting of pipe flow loop tests and strength tests, has been implemented in order to demonstrate the technical feasibility of process integration within industry. An economic analysis has demonstrated that glass is competitive in cost relative to cement and a socioeconomic study has further indicated that the utilization of glass in mine backfill would create a new market for waste glass that requires less processing and reduces costs.