Ettringite formation in lime-remediated mine tailings: II. Experimental study

Laboratory experiments were carried out to assess the potential of forming ettringite in lime-remediated sulphidic mine tailings. The crucial parameters in optimizing and stabilizing the formation of ettringite in mine tailings are the availability of calcium, aluminum, sulphate and high pH environment. The optimization experiments revealed that for the tailings sample under study, 5% lime is the threshold of the lime requirement to establish the required pH condition for the formation and precipitation of ettringite. Attaining and maintaining such a high pH is necessary for ettringite formation. The high metallic content of the tailings sample partially replaced the required trivalent aluminum from the ettringite structure and reduced the required stochiometric amounts of aluminum needed to form ettringite. The solubility of the admixtures (i.e. calcium and aluminum compounds) increases with the increase of the water content of the sample. However, the potential of reusing the treated tailings constrains the water content of the mixtures. Therefore, the optimum water content of the sample was chosen based on the workability characteristics of the mixture.Laboratory experiments were carried out to assess the potential of forming ettringite in lime-remediated sulphidic mine tailings. The crucial parameters in optimizing and stabilizing the formation of ettringite in mine tailings are the availability of calcium, aluminum, sulphate and high pH environment. The optimization experiments revealed that for the tailings sample under study, 5% lime is the threshold of the time requirement to establish the required pH condition for the formation and precipitation of ettringite. Attaining and maintaining such a high pH is necessary for ettringite formation. The high metallic content of the tailings sample partially replaced the required trivalent aluminum from the ettringite structure and reduced the required stochiometric amounts of aluminum needed to form ettringite. The solubility of the admixtures (i.e. calcium and aluminum compounds) increases with the increase of the water content of the sample. However, the potential of reusing the treated tailings constrains the water content of the mixtures. Therefore, the optimum water content of the sample was chosen based on the workability characteristics of the mixture.

Authors
Hossein M.1, 3 , Mohamed A.M.O.2, 4, 5 , Hassani F.P.1, 6, 7, 8, 9, 10 , Elbadri H.1, 8, 11
Journal
Number of issue
1029
Language
English
Pages
75-80
Status
Published
Volume
92
Year
1999
Organizations
  • 1 Mining and Metallurgical Engineering, McGill University, Montreal, Que., Canada
  • 2 Civil Engineering, United Arab Emirates University, Al-Ain, United Arab Emirates
  • 3 Dept. Civ. Eng. and Appl. Mechanics, McGill University, Canada
  • 4 Department of Civil Engineering, McGill University, Canada
  • 5 Department of Civil Engineering, United Arab Emirates University, United Arab Emirates
  • 6 Department of Mining Engineering, Nottingham University, United Kingdom
  • 7 Ray Mining Company
  • 8 Dept. of Mining and Metall. Eng., McGill University, Canada
  • 9 Can. Ctr. Automat. Robotics Mining
  • 10 CIM
  • 11 Friendship University, Moscow, Russian Federation
Keywords
Aluminum; Ettringite formation; Lime-remediated sulphidic mine tailings; Mine tailings; Rock mechanics; Tailings; Water to solid ratio; X-ray difraction spectroscopy
Date of creation
19.10.2018
Date of change
19.10.2018
Short link
https://repository.rudn.ru/en/records/article/record/564/