Recycle Domestic Wastewater by Biotechnology

This paper presents the results of research on the effectiveness of treating COD and nitrogenous compounds by biological treatment systems, using mobile media, the system is operated continuously in 4 different stages: Phase 1 with a hydraulic retention time (HRT) of 6 h, phase 2 of 7 h, phase 3 of 8 h and phase 4 of 8 h, with addition of the microorganism substrate to the aerobic biological tank and anaerobic. Aeration rates in different periods are respectively1 Ln/L*min, 2 Ln/L*min, 3 Ln/L*min, 4 Ln/L*min. During the operation of the system, the concentration of MLSS in aerobic tanks reached 2500 - 7210 mg/L, in anaerobic tanks reached 4000 - 8140 mg/L. The research results show that the COD, NH4+-N, NO3--N, NO2--N content at the input of the system have the corresponding values in the range of 100 - 230; 60 - 70, 0.226 - 0.330 and 0.032 - 0.072 mg/L respectively. In all 4 operation phases, at the outflow, the content of COD remains negligible. In phase 4, after going through the treatment system, the removal efficiency of NH4+-N is highest. Its content is only 3.04 � 0.13 mg/L. The content of NO3--N reaches 0.04 � 0.021 mg/L and the content of NO2--N reaches 0.01 � 0.001 mg/L. The results show that this system can be used to treat COD and nitrogen compounds that meet the standards of domestic water and can continue to develop this technology to provide for places where clean water is scarce.