Nanohybrid membrane in algal-membrane Photoreactor: Microalgae cultivation and wastewater polishing

In this study, Chlorella vulgaris microalgae was cultivated in synthetic wastewater in an A-MPR for ammoniacal-nitrogen and phosphorus recovery and the wastewater was further filtered using Ag/GO-PVDF and com-PVDF membranes to obtain high quality water. Spectrophotometer was used to analyze the chemical oxidation demand (COD), ammoniacal nitrogen (NH3-N) and phosphate (PO43−). The concentration of proteins and carbohydrates were measured using Bradford method and phenol-sulfuric acid method, respectively. The COD of the synthetic wastewater was reduced from 180.5 ± 5.6 ppm to 82 ± 2.6 ppm due to nutrient uptake by microalgae. Then, the Ag/GO-PVDF membrane was used to further purify the microalgae cultivated wastewater, resulting in a low COD permeate of 31 ± 4.6 ppm. The high removal rate of proteins (100%) and carbohydrates (86.6%) as the major foulant in microalgae filtration, with low membrane fouling propensity of Ag/GO-PVDF membrane are advantageous for the sustainable development of the microalgae production. Hence, the integrated A-MPR system is highly recommended as a promising approach for microalgae cultivation and wastewater polishing treatment.
Source: Chinese Journal of Chemical Engineering - Category: Chemistry Source Type: research