Two sequencing batch reactors, one with the conventional anoxic and aerobic (AO) process and the other with the multiple AO process, were operated to examine characteristics of biological nitrogen removal, especially of the multiple AO process. The long-term operation showed that the total nitrogen removal percentage of the multiple AO reactor was 38.7% higher than that of the AO reactor. In th...

background: the presence of chemical compounds has different effects on the rate of degradation of materials and on changing dominant microorganisms in the biological degradation processes. these effects are related to the type and concentration of compounds. this study was to evaluate the effect of different concentrations of glucose as a growth substrate on phenol removal efficiency and micro...

a biofilm sequencing batch reactor with a volume of 1.42 m3, nylon nets providing a 4,140 m2/m3 support area for biofilms and an automated operation with 8 hour cycles was studied. the duration of the experiment was 135 days. removal efficiencies e≥ 80% were obtained for carbonaceous matter, producing an effluent with 31±26.8 mg/l of filtered cod, 7±3.6 mg/l of bod5 and 12±3.2 mg/l of toc. the ...

hospital wastewater has special importance since having pathogens, radioactive materials, pharmaceutical wastes and heavy metals. removing them into environment without any treatment may cause serious problems for the public health. membrane biological reactor is the combination of the activated sludge and membrane filters. this research has investigated the performance of the nano-filtration i...