Algal strains capable of producing electricity were isolated and screened on electrogenicity.
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Coelastrella sp. was screened among the isolates and redox potential ranged from −0.8 V to 0.4 V
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The current density of Coelastrella sp. on waste water was observed as 31.4 mW m−2.
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Coelastrella sp. can be employed to facilitate nutrient removal in dairy waste water treatment.
Abstract
This paper illustrates the potential of unicellular microalgae in electricity production in concurrence with wastewater treatment. Our study focused on the isolation of microalgal strains from various aquatic sources. Cyclic voltammetry was performed to detect the electrogenic activity and out of 18 algal isolates, six algal strains were screened. Coelastrella sp. from the paddy field revealed the well-defined redox peak and its analyzed EPS production was 13.79 mg/mL which paves way to hydrated biofilm matrix assisting in better electrogenicity. Its potential to remove nutrients in wastewater was assessed under lab-scale race way pond. Significant decrease in N, P, BOD, COD, and TOC was observed. The removal efficiency of NH4-N, NO3-N, P, BOD, COD and TOC were 90.38, 90.24, 66.75, 67.15, 69.44, and 83.51 respectively. To the best of our knowledge, EPS production, electrogenic activity and their utility in waste water treatment are reported for the first time in Coelastrella sp.
