TY - JOUR
T1 - Removal of inert COD and trace metals from stabilized landfill leachate by granular activated carbon (GAC) adsorption
AU - Mohammad-Pajooh, Ehsan
AU - Turcios, Ariel E.
AU - Cuff, Graham
AU - Weichgrebe, Dirk
AU - Rosenwinkel, Karl Heinz
AU - Vedenyapina, M. D.
AU - Sharifullina, L. R.
N1 - Funding Information:
This research was funded in part by Deutscher Akademischer Austauschdienst (DAAD) and the Bundesministerium für Bildung und Forschung (BMBF). Authors are also grateful to the Division of Structural Studies of the Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences for studying the samples by electron microscopy and to the Mendeleev Center of Collective Use for studying the porous structure of activated carbon samples.
PY - 2018/12/15
Y1 - 2018/12/15
N2 - Landfills in Germany are currently approaching stabilization phase; as a result removal of inert organics and potentially toxic elements in the leachate is becoming a primary concern. Dissolved air floatation (DAF) at the secondary stage reduces only 27% of the residual chemical oxygen demand (COD) in the investigated treatment systems; downstream granular activated carbon (GAC) units are required to further reduce COD concentration by 40–56% to meet indirect discharge or direct discharge limits respectively. Therefore, in this study performance in terms of COD and trace metals adsorption of different types of granular activated carbon were compared over different contact times and dosages. GAC 1 with Brunauer-Emmett-Teller (BET) surface area of 719.5 ± 2.1 m2/g and average pore diameter (D) of 4.81 nm was identified to be inappropriate for treatment of leachate from this landfill. GAC 2 (with BET of 1513.7 ± 6.4 m2/g and D of 3.50 nm) was feasible for COD reduction from DAF-pretreated leachate, while GAC 3 (with BET of 644.5 ± 2.6 m2/g and D of 5.65 nm) can be coupled either with biological step alone, or as a tertiary step after the DAF unit. Moreover, as COD is the primary remaining contaminant of interest after secondary and tertiary treatment, spectrometer probes provide a close estimation of COD concentration for use in online monitoring. Beside COD removal, GAC 3 also confirmed the effectiveness of trace metals adsorption even at trace level, as it removed 66, 64, 48, 47, 43, and 25% of copper, cobalt, chromium, manganese, nickel, and zinc, respectively.
AB - Landfills in Germany are currently approaching stabilization phase; as a result removal of inert organics and potentially toxic elements in the leachate is becoming a primary concern. Dissolved air floatation (DAF) at the secondary stage reduces only 27% of the residual chemical oxygen demand (COD) in the investigated treatment systems; downstream granular activated carbon (GAC) units are required to further reduce COD concentration by 40–56% to meet indirect discharge or direct discharge limits respectively. Therefore, in this study performance in terms of COD and trace metals adsorption of different types of granular activated carbon were compared over different contact times and dosages. GAC 1 with Brunauer-Emmett-Teller (BET) surface area of 719.5 ± 2.1 m2/g and average pore diameter (D) of 4.81 nm was identified to be inappropriate for treatment of leachate from this landfill. GAC 2 (with BET of 1513.7 ± 6.4 m2/g and D of 3.50 nm) was feasible for COD reduction from DAF-pretreated leachate, while GAC 3 (with BET of 644.5 ± 2.6 m2/g and D of 5.65 nm) can be coupled either with biological step alone, or as a tertiary step after the DAF unit. Moreover, as COD is the primary remaining contaminant of interest after secondary and tertiary treatment, spectrometer probes provide a close estimation of COD concentration for use in online monitoring. Beside COD removal, GAC 3 also confirmed the effectiveness of trace metals adsorption even at trace level, as it removed 66, 64, 48, 47, 43, and 25% of copper, cobalt, chromium, manganese, nickel, and zinc, respectively.
KW - Activated carbon
KW - Adsorption
KW - COD reduction
KW - Dissolved air floatation
KW - Leachate treatment
KW - Trace metals
UR - https://www.scopus.com/pages/publications/85053180501
U2 - 10.1016/j.jenvman.2018.09.020
DO - 10.1016/j.jenvman.2018.09.020
M3 - Article
C2 - 30219600
AN - SCOPUS:85053180501
SN - 0301-4797
VL - 228
SP - 189
EP - 196
JO - Journal of Environmental Management
JF - Journal of Environmental Management
ER -