13 Reigning Technologies and Their Challenges for Antibiotics …
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from 0.001 to 1 μm. UF is primarily used to treat wastewater (WW) generated from
the paints industries, dye industries, leather industries, etc. and where the recycling
of WW is prior concerned. Also used as pretreatment where NF or RO is used. Better
efficiency then MF but having the same disadvantages as MF.
Nanofiltration (NF) is the membrane which has pore size/diameter in between
UF and RO. It has better efficiency than UF and requires low pressure to operate
as compared to RO. Mechanical sieving is the dominant mechanism in the removal
of colloidal molecules, and however, chemical interaction is the dominant mechanism in the removal of metals ions. Nanofiltration membrane technique is efficient
then ultrafiltration membrane in the removal of antibiotics contaminant. In UFM,
adsorption is the predominant mechanism, whereas in NFM, the size of exclusion
and electrostatic repulsion is dominant retention mechanism (Acero et al. 2010). pH
has a negative effect on the NFM process and slightly positive on UFM. Membrane
fouling, cake formation, and blocking of pores are the main problems in the UFM as
well as in NFM.
Reverse osmosis is the first membrane process which extensively used to treat
the contaminated water. In RO process, flow takes place against the osmotic pressure gradient and size pores in the membrane are very small due to these factors
as the energy requirement of this technique is high. RO techniques are very efficient to reduce the high concentration dissolved salts but it has certain drawbacks in
the removal of an organic contaminant. Effectiveness of these membrane processes
depends upon the mechanical and chemical properties of membrane material like
porosity, mechanical resistance, etc. In RO, mostly polymeric material for the membrane is used. This treatment does not require thermal energy but requires electrical
energy for the pump so that, pump feeds inffluent. Membrane fouling or damaging
is the frequent problem rising in the RO process. Sometimes RO techniques not able
to retain fine chemical molecules due to this RO with carbon filters are provided.
The yield of this process is very low, whereas the efficiency of removal is very high
as compared to other membrane techniques. The research have been done to modify
the conventional osmosis process like forward osmosis (Zheng et al. 2015), forward
osmosis combined with electrochemical oxidation (Liu et al. 2015) (Table 13.3).
13.4.2 In Situ Treatment Processes
A process is used to treat contaminants at the field itself is known as in situ treatment
processes. There are two types of in situ treatments that are constructed: wetlands
and integrated constructed wetlands.
13.4.2.1 Constructed Wetlands
A constructed wetland (CW) is a man-made wetland constructed to treat municipal
or industrial effluent (Chen et al. 2016b, c), greywater or stormwater runoff, etc. It
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from 0.001 to 1 μm. UF is primarily used to treat wastewater (WW) generated from
the paints industries, dye industries, leather industries, etc. and where the recycling
of WW is prior concerned. Also used as pretreatment where NF or RO is used. Better
efficiency then MF but having the same disadvantages as MF.
Nanofiltration (NF) is the membrane which has pore size/diameter in between
UF and RO. It has better efficiency than UF and requires low pressure to operate
as compared to RO. Mechanical sieving is the dominant mechanism in the removal
of colloidal molecules, and however, chemical interaction is the dominant mechanism in the removal of metals ions. Nanofiltration membrane technique is efficient
then ultrafiltration membrane in the removal of antibiotics contaminant. In UFM,
adsorption is the predominant mechanism, whereas in NFM, the size of exclusion
and electrostatic repulsion is dominant retention mechanism (Acero et al. 2010). pH
has a negative effect on the NFM process and slightly positive on UFM. Membrane
fouling, cake formation, and blocking of pores are the main problems in the UFM as
well as in NFM.
Reverse osmosis is the first membrane process which extensively used to treat
the contaminated water. In RO process, flow takes place against the osmotic pressure gradient and size pores in the membrane are very small due to these factors
as the energy requirement of this technique is high. RO techniques are very efficient to reduce the high concentration dissolved salts but it has certain drawbacks in
the removal of an organic contaminant. Effectiveness of these membrane processes
depends upon the mechanical and chemical properties of membrane material like
porosity, mechanical resistance, etc. In RO, mostly polymeric material for the membrane is used. This treatment does not require thermal energy but requires electrical
energy for the pump so that, pump feeds inffluent. Membrane fouling or damaging
is the frequent problem rising in the RO process. Sometimes RO techniques not able
to retain fine chemical molecules due to this RO with carbon filters are provided.
The yield of this process is very low, whereas the efficiency of removal is very high
as compared to other membrane techniques. The research have been done to modify
the conventional osmosis process like forward osmosis (Zheng et al. 2015), forward
osmosis combined with electrochemical oxidation (Liu et al. 2015) (Table 13.3).
13.4.2 In Situ Treatment Processes
A process is used to treat contaminants at the field itself is known as in situ treatment
processes. There are two types of in situ treatments that are constructed: wetlands
and integrated constructed wetlands.
13.4.2.1 Constructed Wetlands
A constructed wetland (CW) is a man-made wetland constructed to treat municipal
or industrial effluent (Chen et al. 2016b, c), greywater or stormwater runoff, etc. It