Coupling intermittent micro-aeration to anaerobic digestion improves tetra-azo dye Direct Black 22 treatment in sequencing batch reactors

Sequencing batch reactor technology for landfill leachate treatment: A state-of-the-art review

“…Aeration plays a significant role in aerobic sludge granulation (Menezes et al, 2019). Slow aeration rate in SBR system could reduce the NOx -(NO2and NO3 -) concentration, which reduces the carbon demand for denitrifying bacteria and leads to more carbon sources available for denitrification process.…”

“…It can be operated by modifying the react phase of system cycle, i.e alternating aeration and mixing under imprecise control conditions of DO, pH, and temperature (Zheng, Zhang, Liu, & Lei, 2018). Intermittent aeration can be a useful strategy for N2O mitigation during wastewater treatment and an alternative to keep low concentrations of oxygen (Menezes et al, 2019). The main advantages of applying intermittent aeration in SBR include enhanced nitrogen removal and decreased the operating costs due to a reduction in the continuous supply of oxygen and the quantity of energy source required for the resulting denitrification phase.…”

Degradation of Azo Dyes: Bacterial Potential for Bioremediation

“…In tests performed in a reactor with a fully anaerobic environment, the decolorization rate ranged from 62.98% to 95.84%, depending on the loading rate of dye in the reactor, which decreased the decolorization with its increase [90]. In the study by Menezes and co-workers [91] the reactor without aeration had the highest decolorization, followed by the intermittent aeration reactor and lastly the continuous aeration reactor, the rates being 81.4%, 76.8%, and 74.5%, respectively. However, the reactor without aeration produced waste with toxic substances, which was not observed in other conditions.…”

“…The use of bioreactors can also be achieved with various combinations and parameters variations such as concentrations of salts, presence of oxygen, and feed rate. Regarding the presence of oxygen, several possibilities have already been studied, namely tests in an anaerobic environment [90]; with continuous micro aeration; intermittent and without aeration [91]; anaerobic starting followed by aerobic [92]; and microaerophilic environments followed by aerobic [93].…”

Evaluation of a Combined System Based on an Upflow Anaerobic Sludge Blanket Reactor (UASB) and Shallow Polishing Pond (SPP) for Textile Effluent Treatment

“…Some researchers highlight that biological processes represent the most economically viable routes for the removal of these contaminants [2,4,6,7]. Biological aerobic and anaerobic processes are based on the activity of heterotrophic and/or autotrophic microorganisms.…”