which use small amount of adsorbent with large surface area (Marquez and Costa
1996). Various types of adsorbents derive from different sources can be used to
adsorb specific adsorbate or target compounds. The best adsorbent for the treatment
of specific target compound can be selected on the basis of higher adsorption
capacity of the adsorbents for target solute to be removed.
Ozone gas is a strong oxidizing agent, and it reacts with inorganic and organic
compounds directly or indirectly by the formation of hydroxyl radicals. It mainly
oxidizes electron-rich molecules containing carbon–carbon double bonds and aromatic alcohols. The uses of ozone gas for the effluent treatment comprise splits of
long-chain compounds and making them biodegradable. The combination of ozonation and aerobic bio-treatment is demonstrated to be an effective method for
destroying lipophilic extractives and hence increases the biodegradability of pulp
and pulp mill wastewater before returning them to the bio-treatment unit
(Kamenev et al. 2008).
Advanced oxidation processes (AOPs) are among the promising technological
approaches that have received interest for the treatment of pulp and paper bleach
effluents. AOPs are employed to oxidize complex organic compounds of wastewater
that are difficult to degrade biologically into simpler end products. The mechanism
of AOPs is based on the generation of very reactive nonselective transient oxidizing
species such as the hydroxyl radicals (OH
•
), which were identified as the dominant
oxidizing species (Al-Rasheed 2005). The most common AOPs are H 2 O 2 , UV/O 3 ,
O 3 , Fenton’s reagent UV/H 2 O 2 , and photochemical processes (Metcalf and Eddy
2003).
8 Biological Approaches (Bioremediation)
for the Treatment of Pulp and Paper Mill Wastewater
Biological treatment (or bioremediation) is an eco-friendly technique that
uses microbes/plants or their enzymes for the treatment and detoxification of industrial effluents containing organic and inorganic pollutants (Chandra et al.
2015; Bharagava et al. 2017a, b; Saxena and Bharagava 2017; Haq et al.
2017, 2018; Haq and Raj 2018; Bharagava et al. 2018; Saxena et al. 2019). Biological treatment method (bioremediation) of paper mill effluents employed several
microorganisms such as bacteria, fungi, algae, and many enzymes, as a single-step
treatment or in combination (biphasic) with other physical and/or chemical methods
(Singhal and Thakur 2009). In comparison to the physicochemical process, biological methods for the treatment of wastewater are considered to be of cost-effective,
environment friendly, and appropriate for BOD and COD reduction from the
wastewater.
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I. Haq and A. Raj
1996). Various types of adsorbents derive from different sources can be used to
adsorb specific adsorbate or target compounds. The best adsorbent for the treatment
of specific target compound can be selected on the basis of higher adsorption
capacity of the adsorbents for target solute to be removed.
Ozone gas is a strong oxidizing agent, and it reacts with inorganic and organic
compounds directly or indirectly by the formation of hydroxyl radicals. It mainly
oxidizes electron-rich molecules containing carbon–carbon double bonds and aromatic alcohols. The uses of ozone gas for the effluent treatment comprise splits of
long-chain compounds and making them biodegradable. The combination of ozonation and aerobic bio-treatment is demonstrated to be an effective method for
destroying lipophilic extractives and hence increases the biodegradability of pulp
and pulp mill wastewater before returning them to the bio-treatment unit
(Kamenev et al. 2008).
Advanced oxidation processes (AOPs) are among the promising technological
approaches that have received interest for the treatment of pulp and paper bleach
effluents. AOPs are employed to oxidize complex organic compounds of wastewater
that are difficult to degrade biologically into simpler end products. The mechanism
of AOPs is based on the generation of very reactive nonselective transient oxidizing
species such as the hydroxyl radicals (OH
•
), which were identified as the dominant
oxidizing species (Al-Rasheed 2005). The most common AOPs are H 2 O 2 , UV/O 3 ,
O 3 , Fenton’s reagent UV/H 2 O 2 , and photochemical processes (Metcalf and Eddy
2003).
8 Biological Approaches (Bioremediation)
for the Treatment of Pulp and Paper Mill Wastewater
Biological treatment (or bioremediation) is an eco-friendly technique that
uses microbes/plants or their enzymes for the treatment and detoxification of industrial effluents containing organic and inorganic pollutants (Chandra et al.
2015; Bharagava et al. 2017a, b; Saxena and Bharagava 2017; Haq et al.
2017, 2018; Haq and Raj 2018; Bharagava et al. 2018; Saxena et al. 2019). Biological treatment method (bioremediation) of paper mill effluents employed several
microorganisms such as bacteria, fungi, algae, and many enzymes, as a single-step
treatment or in combination (biphasic) with other physical and/or chemical methods
(Singhal and Thakur 2009). In comparison to the physicochemical process, biological methods for the treatment of wastewater are considered to be of cost-effective,
environment friendly, and appropriate for BOD and COD reduction from the
wastewater.
348
I. Haq and A. Raj