Following the Fukushima nuclear accident of March 11, 2011, soil and water were contaminated by radioactive cesium. Moreover, radioactive cesium was found in the ocean sludge in Tokyo Bay, carried by rivers flowing into the bay. The cesium adsorbed in the sludge cannot easily be removed. The objective of this study was to investigate the effect of the addition of bacteria to the micro-bubble ci...

micro flora of the effluents from a dairy factory in tehran(pegah dairy processing plant) were isolated and screened for their ability to reduce the organic matter content and cod of the effluents. 10 bacteria were selected due to  reduction in cod content from the 4th to 6th day of incubation at 30 °c and  ph =11. highest cod reduction were obtained by two isolates, bp3 and bp4, 70.7 % and 69....

in this study, activated sludge process for wastewater treatment in a refinery was investigated. for such purpose, a laboratory scale rig was built. the effect of several parameters such as temperature, residence time, effect of leca (filling-in percentage of the reactor by leca) and uv radiation on cod removal efficiency were experimentally examined. maximum cod removal efficiency was obtained...

Activated sludge treatment is one of the most popular biological processes for wastewater treatment. Detection of activated sludge structures from complex substrates such as soil and water is not easy. A rapid and effective method for extracting high molecular weight amplifiable DNA from activated sludge was modified. Five nanogram quantities of DNA per milligram activated sludge were recovered...

Activated sludge process has been widely adopted to remove pollutants in wastewater treatment plants (WWTPs). However, stable operation of activated sludge process is often compromised by the occurrence of filamentous bulking. The aim of this study is to build a proper model for timely diagnosis and prediction of filamentous sludge bulking in an activated sludge process. This study developed a ...

This work deals with the effect of combined microwave-ultrasonic pretreatment on the anaerobic biodegradability of primary, excess activated and mixed sludge. The characteristics, biodegradability and anaerobic digester performance for untreated primary, excess activated and mixed sludge were compared to combined microwave-ultrasonic pretreated primary, excess activated and mixed sludge. All sl...

A laboratory-scale anaerobic/anoxic/oxic system operated at the hydraulic retention times (HRT) of 20, 40, and 60 h with mixed liquor suspended solids (MLSS) concentrations of 3 g/L and 6 g/L was considered for treating chemical industrial wastewater rich in complex organic compounds and total dissolved solids. Extending the HRT and increasing the MLSS concentration resulted in higher removal e...

A simple experimental set-up was used to study the treatability aspect of phenolic wastewater. Three types of systems: i) activated sludge (A.S), ii) granular activated carbon (A.C) and iii) activated sludge plus activated carbon (A.S + A.C) were experimented under different phenol loadings (100, 200 and 300 mg/l) and different flow rates (21.6 and 43.2 l/d) with initial COD concentration 500 m...

Despite the fact that there are wastewater treatment plants (WWTPs) currently operational across Iran and great advances have been made in this area, there are still problems in the design, construction, and operation of WWTPs with large nonlinear systems, varying flow rates, and pollution charges. The objective of this study was to investigate the effect of operating parameters including the r...