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.com
Volume 8, Issue 8 (Suppl)
J Earth Sci Clim Change
ISSN: 2157-7617 JESCC, an open access journal
Earth Science Congress 2017
September 18-19, 2017
September 18-19, 2017 Hong Kong
6
th
International Conference on
Earth Science and Climate Change
Passive treatment technologies for the treatment of AMD from abandoned coal mines, Emalahleni,
South Africa: Column experiments
Mpule Gloria Dube
1
, Novhe O
1
, Ramasenya K
1
and Van Zweel N
2
1
Council for Geoscience, South Africa
2
North-West University, South Africa
A
cid mine drainage (AMD) production from abandoned and ownerless coal mines is a huge environmental problem
worldwide. Characteristics of AMD includes low pH (<4), high sulfate (SO
4
) concentrations, high acidity levels and
potentially hazardous metals such as Al, Fe and Mn. Passive treatment technologies for AMD remediation can function in
remote areas with low costs of operation, monitoring and maintenance and therefore are practical for setting up on abandoned
mine sites. Even though such systems have been used to treat acid mine water efficiently, limitations such as coating and
clogging as a result of Al
3+
and Fe
3+
oxyhydroxide precipitates have been reported. For solving the clogging problems associated
with most of the passive treatments, dispersed alkaline substrate (DAS) was introduced in Spain by Rotting, et al., 2008. A
DAS is a system composed of coarse matrix (e.g., wood shavings: Provide and maintain high permeability) mixed with a fine
grained alkaline material (e.g., limestone: Provides a bulk reactive surface area, where it will dissolve and react with AMD
before it is coated). The main aim of the study was to investigate the effectiveness of the DAS system in treating AMD from
an abandoned coal mine and compare it with the traditional reducing and alkalinity producing system (RAPS). The column
experiments remediated acid water successfully for 21 weeks after which the DAS system clogged while RAPS was continuing
to treat AMD successfully. For assessment of the treatment systems water parameters such as pH, EC, Redox, Total Dissolved
Solids (TDS), concentrations of metals and metalloids were analyzed weekly. Both treatment systems were able to raise the pH
from an average of 3 to 8. Contaminants such as Fe, Al, and Zn were completely removed. Mn concentrations were reduced but
were still above the standards. Minimal SO
4
reduction was also noted in both the systems.
gdube@geoscience.org.zaJ Earth Sci Clim Change 2017, 8:8 (Suppl)
DOI: 10.4172/2157-7617-C1-031