754
Investigation of Continuous Fixed-Bed Column Adsorption
Simulation Using COMSOL Multiphysics for the Removal of
Arsenic from Mine Wastewater Using Goethite
Francesca Valeri.e., T. Cabanlig, Djoan Kate T. Tungpalan, Candy C. Mercado
Department of Mining, Metallurgical and Materials Engineering, University of the Philippines Diliman
ABSTRACT: In light of the resurgence of mining in the Philippines, this study explores sustainable practices
by investigating the use of goethite as an adsorbent for removing arsenic, a heavy metal, from mine wastewater.
Using COMSOL Multiphysics for simulation, the column bed height (1 m and 0.5 m), flow rate (200 mL/min
and 1000 mL/min), and initial concentration (0.08 mg/L and 1 mg/L) of the species were varied. The effects
of these parameters were determined for the resulting column saturation time, to provide insights on how these
factors can affect column design. Results reveal that a higher column bed height, reduced flow rate, and lower
species concentration cause an increase in the column saturation time, prolonging the operational duration and
useability of the column. Using the studied parameters, the simulations showed a percent metal removal up
to 90.45%. Overall, the findings offer insights into wastewater treatment for sustainable mining practices and
potential resource recovery.
Keywords: Fixed-bed column, adsorption, goethite, arsenic
INTRODUCTION
Metallic ores are a valuable resource for various industrial
applications. Nevertheless, it is equally important to prac-
tice responsible environmental stewardship while handling
these materials alongside acknowledging their economic
significance. Metallic ores contain heavy metals that can be
released into bodies of water upon exposure to the envi-
ronment. These heavy metals are non-biodegradable, envi-
ronmentally persistent contaminants with the potential for
bioaccumulation and are toxic to living organisms as well.
(Ali et al., 2019) Due to these characteristics, it is in the
best interest of the minerals industry to avoid the discharge
of these given the large volume of material typically being
processed and the large amounts of water needed for unit
operations. One such heavy metal of concern is arsenic,
which is prevalent in copper-arsenide ores. According to
the Department of Environment and Natural Resources
(DENR) of the Philippines, the effluent standards for arse-
nic in Water Body Classification D and SD is 0.08 mg/L
(Department of Environment and Natural Resources of the
Philippines 2016).
There are several heavy metal removal techniques
being explored, such as chemical precipitation, photoca-
talysis, flotation, ion exchange, electrochemical processes,
adsorption, membrane technologies, and coagulation-floc-
culation. Among these, adsorption provides an advantage
due to its simplicity, flexibility in designing the adsorp-
tion system, low cost of adsorbents, and reversibility of
the process through desorption. (Rajendran et al., 2022)
Other techniques usually operate at a higher cost, produce
large amounts of sludge, and are generally more complex
in design.
Investigation of Continuous Fixed-Bed Column Adsorption
Simulation Using COMSOL Multiphysics for the Removal of
Arsenic from Mine Wastewater Using Goethite
Francesca Valeri.e., T. Cabanlig, Djoan Kate T. Tungpalan, Candy C. Mercado
Department of Mining, Metallurgical and Materials Engineering, University of the Philippines Diliman
ABSTRACT: In light of the resurgence of mining in the Philippines, this study explores sustainable practices
by investigating the use of goethite as an adsorbent for removing arsenic, a heavy metal, from mine wastewater.
Using COMSOL Multiphysics for simulation, the column bed height (1 m and 0.5 m), flow rate (200 mL/min
and 1000 mL/min), and initial concentration (0.08 mg/L and 1 mg/L) of the species were varied. The effects
of these parameters were determined for the resulting column saturation time, to provide insights on how these
factors can affect column design. Results reveal that a higher column bed height, reduced flow rate, and lower
species concentration cause an increase in the column saturation time, prolonging the operational duration and
useability of the column. Using the studied parameters, the simulations showed a percent metal removal up
to 90.45%. Overall, the findings offer insights into wastewater treatment for sustainable mining practices and
potential resource recovery.
Keywords: Fixed-bed column, adsorption, goethite, arsenic
INTRODUCTION
Metallic ores are a valuable resource for various industrial
applications. Nevertheless, it is equally important to prac-
tice responsible environmental stewardship while handling
these materials alongside acknowledging their economic
significance. Metallic ores contain heavy metals that can be
released into bodies of water upon exposure to the envi-
ronment. These heavy metals are non-biodegradable, envi-
ronmentally persistent contaminants with the potential for
bioaccumulation and are toxic to living organisms as well.
(Ali et al., 2019) Due to these characteristics, it is in the
best interest of the minerals industry to avoid the discharge
of these given the large volume of material typically being
processed and the large amounts of water needed for unit
operations. One such heavy metal of concern is arsenic,
which is prevalent in copper-arsenide ores. According to
the Department of Environment and Natural Resources
(DENR) of the Philippines, the effluent standards for arse-
nic in Water Body Classification D and SD is 0.08 mg/L
(Department of Environment and Natural Resources of the
Philippines 2016).
There are several heavy metal removal techniques
being explored, such as chemical precipitation, photoca-
talysis, flotation, ion exchange, electrochemical processes,
adsorption, membrane technologies, and coagulation-floc-
culation. Among these, adsorption provides an advantage
due to its simplicity, flexibility in designing the adsorp-
tion system, low cost of adsorbents, and reversibility of
the process through desorption. (Rajendran et al., 2022)
Other techniques usually operate at a higher cost, produce
large amounts of sludge, and are generally more complex
in design.