Feasibility of combined anaerobic-aerobic system for textile wastewater contained C. I. Acid Red 88 dye treatment: HRT effects and functional resilience

An integrated continuous anaerobic–aerobic system has been employed as the treatment for synthetic textile wastewater contained C. I. Acid Red 88 dye. A laboratory scale of upflow anaerobic sludge bed (UASB) flowed by activated treatment was operated at hydraulic residence time (HRT) of 24, 12, 6, and 3 h. the system showed high performance on the removal of color and COD within the HRT ranged between 24 and 6 hrs. At different organic loading rates (OLR), the chemical oxygen demand (COD) removal in the UASB was reached to 86.6% and up to 97% were obtained in the aerobic reactor. The system performance appeared to be more resilient to the inapt decrease in the HRT. The experimental analysis results indicated that the maximum methane yield was 13.2 mmol CH4 g COD-1 d-1 at HRT 6 h, and the system is expected to have a better economic performance under HRT 12 h.