The purification of micro-polluted water for drinking water can play an important role in solving water crisis. To investigate the effects of spectral composition on nutrient removal and biofuel feedstock production using duckweed, Landoltia punctata was cultivated in different spectral compositions in micro-polluted water. Results showed that the nitrogen and phosphorus removal efficiency were 99.4% and 93.5% at an recommended red and blue light photon intensity mixture ratio of 2:1. Meanwhile, maximum growth rate of duckweed (11.37 g/m2/day) was observed at red/blue = 2:1. In addition, maximum starch accumulation rate of duckweed was found to be 6.12 g/m2/day, with starch content of 36.63% at red/blue = 4:1, which was three times higher when compared to that of white light. Moreover, the recommended ratio of red and blue light was validated by economic efficiency analysis of energy consumptions. These findings provide a sustainable environmental restoration method to transform water micro-pollutants to available substances.
Keywords: Blue light; Energy consumptions; Light photon intensity; Nutrient removal; Recommended mixture ratio; Red light; Starch accumulation.
© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.