Biotechnology for Zero Waste – Emerging Waste Management Techniques (Chaudhery Mustansar Hussain (editor) etc.)

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Usage of Microalgae: A Sustainable Approach to

Wastewater Treatment

Kumudini B. Satyan, Michael V. L. Chhandama, and Dhanya V. Ranjit

JAIN (Deemed-to-be University), School of Sciences (Block-I), Department of Biotechnology, #18/3, 9th Main

Road, 3rd Block, Jayanagar, Bangalore, Karnataka 560011, India

11.1

Introduction

Water is one of the most valuable resources for the sustenance of life on the planet.

However, industrialization and high rate of urbanization led to an emanation of

large quantities of wastewater from different manufacturing industries, agricultural

fields, and domestic activities. Water has been polluted by toxic matters from

industrial wastes, mining activities, domestic waste, pesticides, chemical fertilizers,

and radioactive wastes. Domestic waste accounts for the highest percentage of

water pollutants followed by livestock industries. Shortage of clean water was

identified as one of the three most rapidly emerging global challenges by the

United Nations Human Development Report. It has been reported that ∼29% of

the world’s population faced shortage of clean water supply. The most common

water pollutants include suspended solids, pathogens, nutrients like nitrogen,

phosphorus and carbon, salts, and oxygen demanding materials. Discharge of

waste into water bodies highly disturbs environmental sustainability. Poor quality

of water has resulted in a high rate of illness and deaths, accounting for ∼50 million

deaths per year worldwide, especially in Africa and Asia. An elevated amount of

water pollutants such as heavy metal, phosphorus, carbon, and nitrogen species

are the major cause of eutrophication in natural waters leading to bigger con-

sequences in the ecosystem including species mortality, biodiversity reduction,

and loss of ecosystem [1]. Therefore, treatment of polluted water is crucial to

ensure a quality living standard. A typical wastewater treatment process includes

preliminary treatment where settleable inorganic solids are removed followed by

primary treatment where suspended organic solids are removed. The next process

is the secondary treatment where dissolved compounds are removed and finally

tertiary treatment involves further elimination of organic pollutants and pathogens

in wastewater. Various technologies and techniques include filtration, floccula-

Biotechnology for Zero Waste: Emerging Waste Management Techniques, First Edition.

Edited by Chaudhery Mustansar Hussain and Ravi Kumar Kadeppagari.