potency to color and COD of wastewater. Results further indicated that color and
COD removal efficiency from wastewater was found 98.2% and 69.8% for batch
experiment and 78.8% and 67.7% for upflow packed bed bioreactor, respectively.
6.5.2.3 Algal Biodegradation
Removal of potentially toxic substances from the wastewater by algal species termed
as phycoremediation. Phycoremediation is a promising, efficient, eco-friendly, costeffective technology. Generally, contaminants removal from wastewater works on
the principle of adsorption and absorption; cell surface adsorption is independent on
cell metabolism but in case of absorption or intracellular uptake depends on cell
metabolism. The capability of algal species for the adsorption and absorption of
contaminants depends on large surface area, higher metal binding affinity on their
cell surface, feasible in metal uptake and storage systems (Ahmad et al. 2020).
Natural ability of alga for uptake of nutrients and heavy metals, and degradation of
organic contaminants is possible via symbiotic association with aerobic bacteria.
Algae showed higher photosynthetic activity due to the presence of pigments and
become greater source of oxygen in an aquatic ecosystem. They can also enhance the
degradation of organic compounds in aerobic condition and helpful in biofuel
production (Majumder et al. 2014; Gupta et al. 2020).
Ali et al. (2018) used Scenedesmus obliquus isolated from phytoplankton community of Nile River for the removal of pharmaceutical compounds from industrial
effluents. Pharmaceutical residues are also considered as an emerging pollutant and
have potential negative impacts on environment. Algal biomass was modified using
alkaline solution and used for biosorption of different pharmaceuticals compounds
namely cefadroxil, paracetamol, ibuprofen, ciprofloxacin, etc. At natural pH, 0.5 g/L
of modified algal biomass has adsorption capacities for cefadroxil, paracetamol,
ibuprofen, and ciprofloxacin as 68 mg/g, 58 mg/g, 42 mg/g, and 39 mg/g, respectively. Results further showed reusability of modified algal biomass for biosorption
of different pharmaceutical compounds; its efficiency is decreased by 4.5% after
three uses. However, there is a need to explore various algal remediation techniques
as an eco-friendly alternatives for a better environmental condition.
6.5.2.4 Integrated Aerobic-Anaerobic Biodegradation
Assessment of some important factors like composition and concentration of contaminants in wastewater, volume generation, cost-effectiveness, treatment susceptibility, environmental impacts, etc., is necessary for the selection of the best
wastewater treatment technology. Wastewater treatments by a combination of aerobic and anaerobic degradation in an individual bioreactor have higher removal
efficiency. Different engineering setups such as rotating biological contactor, membrane bioreactor, trickling filter, sequential batch reactor, etc., are used for aerobic
degradation of contaminant. Upflow anaerobic film, membrane anaerobic reactor
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P. K. Singh and R. K. Sharma
COD removal efficiency from wastewater was found 98.2% and 69.8% for batch
experiment and 78.8% and 67.7% for upflow packed bed bioreactor, respectively.
6.5.2.3 Algal Biodegradation
Removal of potentially toxic substances from the wastewater by algal species termed
as phycoremediation. Phycoremediation is a promising, efficient, eco-friendly, costeffective technology. Generally, contaminants removal from wastewater works on
the principle of adsorption and absorption; cell surface adsorption is independent on
cell metabolism but in case of absorption or intracellular uptake depends on cell
metabolism. The capability of algal species for the adsorption and absorption of
contaminants depends on large surface area, higher metal binding affinity on their
cell surface, feasible in metal uptake and storage systems (Ahmad et al. 2020).
Natural ability of alga for uptake of nutrients and heavy metals, and degradation of
organic contaminants is possible via symbiotic association with aerobic bacteria.
Algae showed higher photosynthetic activity due to the presence of pigments and
become greater source of oxygen in an aquatic ecosystem. They can also enhance the
degradation of organic compounds in aerobic condition and helpful in biofuel
production (Majumder et al. 2014; Gupta et al. 2020).
Ali et al. (2018) used Scenedesmus obliquus isolated from phytoplankton community of Nile River for the removal of pharmaceutical compounds from industrial
effluents. Pharmaceutical residues are also considered as an emerging pollutant and
have potential negative impacts on environment. Algal biomass was modified using
alkaline solution and used for biosorption of different pharmaceuticals compounds
namely cefadroxil, paracetamol, ibuprofen, ciprofloxacin, etc. At natural pH, 0.5 g/L
of modified algal biomass has adsorption capacities for cefadroxil, paracetamol,
ibuprofen, and ciprofloxacin as 68 mg/g, 58 mg/g, 42 mg/g, and 39 mg/g, respectively. Results further showed reusability of modified algal biomass for biosorption
of different pharmaceutical compounds; its efficiency is decreased by 4.5% after
three uses. However, there is a need to explore various algal remediation techniques
as an eco-friendly alternatives for a better environmental condition.
6.5.2.4 Integrated Aerobic-Anaerobic Biodegradation
Assessment of some important factors like composition and concentration of contaminants in wastewater, volume generation, cost-effectiveness, treatment susceptibility, environmental impacts, etc., is necessary for the selection of the best
wastewater treatment technology. Wastewater treatments by a combination of aerobic and anaerobic degradation in an individual bioreactor have higher removal
efficiency. Different engineering setups such as rotating biological contactor, membrane bioreactor, trickling filter, sequential batch reactor, etc., are used for aerobic
degradation of contaminant. Upflow anaerobic film, membrane anaerobic reactor
138
P. K. Singh and R. K. Sharma