NUTRIENT SEQUESTRATION, BIOMASS PRODUCTION BY MICROALGAE AND PHYTOREMEDIATION OF SEWAGE WATER

Abstract

The present work was aimed at analysing the role of inoculated microalgae in nutrient dynamics, bioremediation and biomass production of sewage water. Preliminary microscopic analyses of sewage water revealed the presence of different algal groups, with predominance of Cyanophyta. Among the inoculated strains, Calothrix showed highest dry cell weight (916.67 mg L⁻¹), chlorophyll and carotenoid content in tap water + sewage water (1:1) treatment. Significant removal of NO₃-N ranging from 57–78% and PO₄-P (44–91%) was recorded in microalgae inoculated tap water + sewage water. The total dissolved solids and electrical conductivity of tap water + sewage water after incubation with Calothrix sp. decreased by 28.5 and 28.0%, accompanied by an increase in dissolved oxygen from 4.4 to 6.4 mg L⁻¹ on the 20th day. Our investigation revealed the robustness of Calothrix sp. in sequestering nutrients (N and P), improving water quality and proliferating in sewage water.

KEY WORDS::

• biomass
• microalgae
• nutrient scavenging
• sewage
• wastewater treatment

ACKNOWLEDGMENTS

The first author is thankful to University Grants Commission, New Delhi for her fellowship. All the authors are thankful to the Department of Botany, Panjab University, Chandigarh; Division of Microbiology, Indian Agricultural Research Institute, New Delhi and Department of Botany, University of Delhi, Delhi for providing the budget and research facilities to carry out the present investigation.