TREATMENT OF RURAL DOMESTIC SEWAGE USING MICROALGA MEDIATED BY TITANATE NANO MATERIALS

The safe disposal of domestic sewage has posed a serious threat to the safety of drinking water sources. Microalgae have remarkable effects on the advanced treatment of domestic sewage, but the sewage has strong inhibitory effects on algae. Nanoparticles have a positive regulatory effect on the growth of microalgae. Therefore, exploring the appropriate nano materials and adding methods, and studying their effects on the treatment of domestic sewage by microalgae are meaningful. In this study, titanate nano materials (TNTs) and microalgae were synergistically used to purify domestic sewage. Different addition methods of TNTs were set up to treat domestic sewage together with five microalgae. The photochemical efficiency of chlorophyⅡ and photosynthetic pigment using different algae species and treatment methods were compared. The superior algae species and efficient treatment methods were screened. The results showed that TNTs could significantly enhance the treatment effect of microalgae on domestic sewage. After the addition of TNTs, microalgae cells all showed aggregation, and the contents of chlorophyll a and carotenoids increased. Inoculation of after Microalgae had the best effect on domestic sewage treatment after TNTs mediated two days later. Tetradesmus obliquus, T. obliquus, Chlorella vulgaris, and Quadricauda sp. had the highest removal rates of COD, NH₃-N, TN, and TP (95.00%, 88.62%, 83.14% and 79.43%), respectively. Compared with microalgae alone, the addition of TNTs significantly increased the degradation rate of pollutants (>10%) and the removal rate from microalgae (>5%). TNTs has a certain application prospect in microalgae advanced treatment of domestic sewage.