Characterization of Green Liquor Dregs, Potentially Useful for Prevention of the Formation of Acid Rock Drainage

Using alternative materials such as residual products from other industries to mitigate the negative effects of acid rock drainage would simultaneously solve two environmental problems. The main residual product still landfilled by sulphate paper mills is the alkaline material green liquor dregs (GL...

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Main Authors: Maria Mäkitalo, Christian Maurice, Yu Jia, Björn Öhlander
Format: Article
Language:English
Published: MDPI AG 2014-04-01
Series:Minerals
Subjects:
Online Access:http://www.mdpi.com/2075-163X/4/2/330
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author Maria Mäkitalo
Christian Maurice
Yu Jia
Björn Öhlander
author_facet Maria Mäkitalo
Christian Maurice
Yu Jia
Björn Öhlander
author_sort Maria Mäkitalo
collection DOAJ
description Using alternative materials such as residual products from other industries to mitigate the negative effects of acid rock drainage would simultaneously solve two environmental problems. The main residual product still landfilled by sulphate paper mills is the alkaline material green liquor dregs (GLD). A physical, mineralogical and chemical characterization of four batches of GLD was carried out to evaluate the potential to use it as a sealing layer in the construction of dry covers on sulphide-bearing mine waste. GLD has relatively low hydraulic conductivity (10−8 to 10−9 m/s), a high water retention capacity (WRC) and small particle size. Whilst the chemical and mineralogical composition varied between the different batches, these variations were not reflected in properties such as hydraulic conductivity and WRC. Due to relatively low trace element concentrations, leaching of contaminants from the GLD is not a concern for the environment. However, GLD is a sticky material, difficult to apply on mine waste deposits and the shear strength is insufficient for engineering applications. Therefore, improving the mechanical properties is necessary. In addition, GLD has a high buffering capacity indicating that it could act as an alkaline barrier. Once engineering technicalities have been overcome, the long-term effectiveness of GLD should be studied, especially the effect of aging and how the sealing layer would be engineered in respect to topography and climatic conditions.
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spelling doaj.art-2ff1a665a2814055862c7225cb9c64e42022-12-22T02:47:17ZengMDPI AGMinerals2075-163X2014-04-014233034410.3390/min4020330min4020330Characterization of Green Liquor Dregs, Potentially Useful for Prevention of the Formation of Acid Rock DrainageMaria Mäkitalo0Christian Maurice1Yu Jia2Björn Öhlander3Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, SE-97187 Luleå, SwedenDepartment of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, SE-97187 Luleå, SwedenDepartment of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, SE-97187 Luleå, SwedenDepartment of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, SE-97187 Luleå, SwedenUsing alternative materials such as residual products from other industries to mitigate the negative effects of acid rock drainage would simultaneously solve two environmental problems. The main residual product still landfilled by sulphate paper mills is the alkaline material green liquor dregs (GLD). A physical, mineralogical and chemical characterization of four batches of GLD was carried out to evaluate the potential to use it as a sealing layer in the construction of dry covers on sulphide-bearing mine waste. GLD has relatively low hydraulic conductivity (10−8 to 10−9 m/s), a high water retention capacity (WRC) and small particle size. Whilst the chemical and mineralogical composition varied between the different batches, these variations were not reflected in properties such as hydraulic conductivity and WRC. Due to relatively low trace element concentrations, leaching of contaminants from the GLD is not a concern for the environment. However, GLD is a sticky material, difficult to apply on mine waste deposits and the shear strength is insufficient for engineering applications. Therefore, improving the mechanical properties is necessary. In addition, GLD has a high buffering capacity indicating that it could act as an alkaline barrier. Once engineering technicalities have been overcome, the long-term effectiveness of GLD should be studied, especially the effect of aging and how the sealing layer would be engineered in respect to topography and climatic conditions.http://www.mdpi.com/2075-163X/4/2/330green liquor dregsacid rock drainagesulphidic mine wastesealing layer
spellingShingle Maria Mäkitalo
Christian Maurice
Yu Jia
Björn Öhlander
Characterization of Green Liquor Dregs, Potentially Useful for Prevention of the Formation of Acid Rock Drainage
Minerals
green liquor dregs
acid rock drainage
sulphidic mine waste
sealing layer
title Characterization of Green Liquor Dregs, Potentially Useful for Prevention of the Formation of Acid Rock Drainage
title_full Characterization of Green Liquor Dregs, Potentially Useful for Prevention of the Formation of Acid Rock Drainage
title_fullStr Characterization of Green Liquor Dregs, Potentially Useful for Prevention of the Formation of Acid Rock Drainage
title_full_unstemmed Characterization of Green Liquor Dregs, Potentially Useful for Prevention of the Formation of Acid Rock Drainage
title_short Characterization of Green Liquor Dregs, Potentially Useful for Prevention of the Formation of Acid Rock Drainage
title_sort characterization of green liquor dregs potentially useful for prevention of the formation of acid rock drainage
topic green liquor dregs
acid rock drainage
sulphidic mine waste
sealing layer
url http://www.mdpi.com/2075-163X/4/2/330
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AT yujia characterizationofgreenliquordregspotentiallyusefulforpreventionoftheformationofacidrockdrainage
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