Sewage Treatment in Campus for Recycling Purpose: A Review
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will highly depend on the porosity, surface area, and hydrophobicity because this will
provide more available sites for contaminants adsorption. Activated carbon such as
fly ash that has been used to treat JUST campus sewage has a removal efficiency of
about 95.19% (Al-Asheh et al. 2013).
The adsorption process of adsorbates from the bulk solution onto the surface of
adsorbates at equilibrium is commonly described by using models such as LangmuirFreundlich (Sips 1948) and Toth (for heterogeneous surfaces) (Toth 1971), the
Tempkin (model for systems with adsorbate–adsorbate interactions) (Tempkin and
Pyzhev 1940), and Frumkin (model for systems with adsorbate–adsorbate interactions) (Frumkin 1925). As compared to other models, Langmuir has been used widely
to describe the adsorption process model at equilibrium.
However, according to Azizian et al. (2018), some assumptions are not met for the
Langmuir mode in certain systems and reveals the need to modify the isotherm model
in a revised form. The primary assumption was logical but the role of solution concentration on desorption rate was unclear and lack of unified method for estimation
of thermodynamics parameters. Furthermore, different values for entropy, S were
identified by using different units of Langmuir equilibrium constant, K L . Besides
that, Langmuir adsorption model is the subsequent application from gas phase to
liquid phase application which leaves an uncertainty.
Filtration
Filtration is a typical energy-saving nonthermal dehydration (liquid) unit operation
that uses filtration media to separate solids and liquids and has attracted wide attention
(Guo et al. 2018). In China, most sewage treatment plants have been using flocculation
and sand filtration as the advanced treatment for reclaimed water prior to disinfection
(Qi et al. 2019). Filtration can be classified into three namely depth filtration, surface
filtration, and membrane filtration (Gholikandi et al. 2012). The media that commonly
used in filtration are coal, silica, sand, and anthracite. Media is either being utilized
as single or in combination of few media. Instead of that, biofilter such as empty fruit
bunch (EFB) can also be used to filter contaminants (Bolong 2016). In conventional
sand filters, most of the solids are removed at or near the surface of sand bed forming
a layer of solids. If the solids concentration is high, head loss increases rapidly, filter
runs are short, and most of the capacity of filter bed is not fully utilized which has
led to dual or multi filtering medium.
In conventional sand filters, most of the solids are removed at or near the surface
of sand bed forming a layer of solids. If the solids concentration is high, head loss
increases rapidly, filter runs are short and most of the capacity of filter bed is not fully
utilized which has led to dual or multi filtering medium (Matsumoto et al. 1982).
Sand filtration has been used to treat campus sewage. Slow sand filtration was the first
principal unit operation used in wastewater treatment which is also known as depth
filtration that involves the removal of particulate material suspended in a liquid by
passing the liquid through a filter bed comprised of granular (sand) or compressible
filter medium (Metcalf and Eddy 2003). The granular medium filtration is commonly
used for achieving supplemental removal of suspended solids following biological
and chemical process (Matsumoto et al. 1982).
219
will highly depend on the porosity, surface area, and hydrophobicity because this will
provide more available sites for contaminants adsorption. Activated carbon such as
fly ash that has been used to treat JUST campus sewage has a removal efficiency of
about 95.19% (Al-Asheh et al. 2013).
The adsorption process of adsorbates from the bulk solution onto the surface of
adsorbates at equilibrium is commonly described by using models such as LangmuirFreundlich (Sips 1948) and Toth (for heterogeneous surfaces) (Toth 1971), the
Tempkin (model for systems with adsorbate–adsorbate interactions) (Tempkin and
Pyzhev 1940), and Frumkin (model for systems with adsorbate–adsorbate interactions) (Frumkin 1925). As compared to other models, Langmuir has been used widely
to describe the adsorption process model at equilibrium.
However, according to Azizian et al. (2018), some assumptions are not met for the
Langmuir mode in certain systems and reveals the need to modify the isotherm model
in a revised form. The primary assumption was logical but the role of solution concentration on desorption rate was unclear and lack of unified method for estimation
of thermodynamics parameters. Furthermore, different values for entropy, S were
identified by using different units of Langmuir equilibrium constant, K L . Besides
that, Langmuir adsorption model is the subsequent application from gas phase to
liquid phase application which leaves an uncertainty.
Filtration
Filtration is a typical energy-saving nonthermal dehydration (liquid) unit operation
that uses filtration media to separate solids and liquids and has attracted wide attention
(Guo et al. 2018). In China, most sewage treatment plants have been using flocculation
and sand filtration as the advanced treatment for reclaimed water prior to disinfection
(Qi et al. 2019). Filtration can be classified into three namely depth filtration, surface
filtration, and membrane filtration (Gholikandi et al. 2012). The media that commonly
used in filtration are coal, silica, sand, and anthracite. Media is either being utilized
as single or in combination of few media. Instead of that, biofilter such as empty fruit
bunch (EFB) can also be used to filter contaminants (Bolong 2016). In conventional
sand filters, most of the solids are removed at or near the surface of sand bed forming
a layer of solids. If the solids concentration is high, head loss increases rapidly, filter
runs are short, and most of the capacity of filter bed is not fully utilized which has
led to dual or multi filtering medium.
In conventional sand filters, most of the solids are removed at or near the surface
of sand bed forming a layer of solids. If the solids concentration is high, head loss
increases rapidly, filter runs are short and most of the capacity of filter bed is not fully
utilized which has led to dual or multi filtering medium (Matsumoto et al. 1982).
Sand filtration has been used to treat campus sewage. Slow sand filtration was the first
principal unit operation used in wastewater treatment which is also known as depth
filtration that involves the removal of particulate material suspended in a liquid by
passing the liquid through a filter bed comprised of granular (sand) or compressible
filter medium (Metcalf and Eddy 2003). The granular medium filtration is commonly
used for achieving supplemental removal of suspended solids following biological
and chemical process (Matsumoto et al. 1982).