An A2O-MBR system for simultaneous nitrogen and phosphorus removal from brewery wastewater

Abstract

Anaerobic/Anoxic/Oxic -Membrane BioReactor (A 2 O-MBR) system was used to enhance simultaneous removal of nitrogen and phosphorus from brewery wastewater. The A 2 O unit containing microorganisms with short solids retention time (SRT) was employed mainly for removal of organic matter and phosphorus together with denitrification. The MBR containing microorganisms with long SRT was employed mainly for nitrification of NH 4 + -N and recirculation of NO 3 − -N. The model of A 2 O-MBR system made from polyacrylic with the capacity of 49.5 liters was operated with hydraulic retention times decreased from 24, 18 to 12 hours corresponding to organic loading rates increased from 0.50, 0.75 to 1.00 kg COD/m 3 .day. The results showed that the model not only treated organic matter well but also nearly completely removed both nitrogen and phosphorus. For all three loading rates, chemical oxygen demand (COD) concentration decreased significantly in the anaerobic and anoxic compartments of the A 2 O unit, indicating that most of organic matter was utilized in the anaerobic and anoxic compartments for phosphorus release and denitrification, respectively. Nitrification in the MBR was almost perfectly completed, with average NH 4 + -N removal efficiencies of over 98%. Denitrification in the anoxic compartment happened as much as possible. Demands for the development of PAOs, which were responsible for enhanced biological phosphorus removal (EBPR) processes, could be provided. For loading rate of 0.75 kg COD/m 3 .day, treatment efficiencies of COD, NH 4 + -N, total nitrogen (TN) and total phosphorus (TP) of the model were the highest as 95.4, 99.2, 86.7 and 84.6%, respectively. Output values of these parameters were within the limits of Vietnam National Technical Regulation on Industrial Wastewater (QCVN 40:2011/BTNMT), column A. The model of A 2 O-MBR system was capable of achieving effluents with very low nitrogen and phosphorus concentrations from brewery wastewater.

Effect of Self-Made TiO2 Nanoparticle Size on the Performance of the PVDF Composite Membrane in MBR for Landfill Leachate Treatment

“…Therefore, pH exerts the strongest effect on the removal of ammonia nitrogen in wastewater by influencing the activity of microorganisms in the biochemical system. MBR is the main agent that removes total nitrogen from nitrification and denitrification in the biochemical system, mainly through the filtration of the ultrafiltration membrane and the biological action of the microorganisms attached to the surface [47,48]. The metabolism of heterotrophic bacteria and the nitrification of nitrifying bacteria in the activated sludge will consume significant basicity during the operation of the MBR system, resulting in a decrease in the pH in the reaction.…”

“…Therefore, pH exerts the strongest effect on the removal of ammonia nitrogen in wastewater by influencing the activity of microorganisms in the biochemical system. MBR is the main agent that removes total nitrogen from nitrification and denitrification in the biochemical system, mainly through the filtration of the ultrafiltration membrane and the biological action of the microorganisms attached to the surface [47,48].…”