Date of Award
Master of Science (MS)
Brain St. Clair
Mine tailings not only pose environmental risks such as dust emission and acid mine drainage but also present geotechnical risks in cases of tailings dam failures which could lead to loss of human life and severe damages to infrastructure. In-situ cementation of tailings has the potential to reduce the risks associated with such failures as well as the related environmental problems. Over the years, different methods of chemically and microbially induced cementation of tailings have been examined many of which have shown promising results on a laboratory scale and some even on a ϐield scale. In this paper, a new inorganic method of inducing tailings cementation is introduced which uses a naturally occurring mineral called trona (Na2CO3•NaHCO3•2H2O). Three methods of introducing dissolved trona, i.e., injections, slurry mixing, and inϐiltration, were tested and the results were compared. All methods were proven successful on a laboratory scale but with different amounts of precipitated calcite at different depths of the samples. The distinctions in precipitation proϐile could have applications in solving common problems associated with tailings including dust emission and liquefaction. Additionally, even distribution of precipitated calcite in the slurry mixing method shows potential in acid mine drainage prevention.
Small, Nathaniel, "TREATMENT OF MINE TAILINGS THROUGH TWO METHODS OF CALCITE PRECIPITATION: (I) USING NATURAL MINERAL TRONA, (II) MICROBIALLY INDUCED CALCITE PRECIPITATION VIA DENITRIFICATION" (2022). Graduate Theses & Non-Theses. 288.