TITLE:
Nutrient Removal Efficiencies of Chlorella vulgaris from Urban Wastewater for Reduced Eutrophication
AUTHORS:
Ravipratap Singh, Rohan Birru, G. Sibi
KEYWORDS:
Chlorella vulgaris, Wastewater, Nutrient Removal, Biomass, Lipid, Eutrophication
JOURNAL NAME:
Journal of Environmental Protection,
Vol.8 No.1,
January
5,
2017
ABSTRACT: Urban
wastewater contains both organic and inorganic nutrients and discharge of
untreated water increases nitrogen and phosphorous content in water bodies
leading to eutrophication problem. Physical and chemical treatment of urban
waste water produces large quantities of waste sludge associated with secondary
pollution. Microalgae can assimilate nutrients especially nitrogen and phosphorous
from wastewater for their growth and produce valuable biomass and lipid. This
study was performed to determine the growth of Chlorella vulgaris in urban wastewater (UWW) and Bold’s basal
medium (BBM) thereby identifying cost effective growth medium for microalga
cultivation. In addition, nutrient removal abilities of C. vulgaris from various dilutions of urban waste water were
explored at 10 days cultivation period. Specific growth rate, biomass and lipid
content were higher in microalgae grown in urban waste water than BBM. The highest
lipid productivity of 14.31 mg·L?1·day?1 was achieved in the culture grown in UWW
medium which exceeded the BBM at 1.15 fold. The amount of nutrient removal
tended to increase with higher dilutions of UWW. Removal rates of upto 87.9%
and 98.4% were recorded for total nitrogen and total phosphorous by C. vulgaris. The results emphasized that
urban waste water as a cost effective growth medium for higher biomass and
lipid production accompanied with the nutrient removal efficiency of microalgae
to reduce eutrophication.