This paper presents the Constructed Wetland Model No1 (CWM1), a general model to describe biochemical transformation and degradation processes for organic matter, nitrogen and sulphur in subsurface flow constructed wetlands. The main objective of CWM1 is to predict effluent concentrations from constructed wetlands without predicting gaseous emissions. CWM1 describes aerobic, anoxic and anaerobi...

This paper presents the results of an investigation on the effects of concentration of cations on activated sludge properties and membrane fouling in submerge membrane bioreactors. The working volume of the experimental setup was two liters. The cellulose acetate membrane was immersed in the bioreactor. The flocculability, settling properties and fouling propensity of activated sludge was measu...

this paper presents the results of an investigation on the effects of concentration of cations on activated sludge properties and membrane fouling in submerge membrane bioreactors. the working volume of the experimental setup was two liters. the cellulose acetate membrane was immersed in the bioreactor. the flocculability, settling properties and fouling propensity of activated sludge was measu...

Wastewater treatment plants are one of the main sources of dissemination of antibiotic resistance genes (ARGs) into the environment. The present study was conducted to determine the prevalence and removal of ARGs in different wastewater treatment processes. A total of 36 samples from raw and final effluent of different activated sludge processes were collected and analyzed. Molecular analysis w...

the activated sludge process is the most used biological wastewater treatment method in the world. sludge bulking is one of the most common problems relateing to activated sludge wastewater treatment, and this fact causes poor settling in secondary sedimentation tank. sludge volume index(svi) and the zone settling velocity(zsv) are parameters to quantify the settleability of activated sludge . ...

Sludge minimization by thermal treatment within activated sludge process was investigated at pilot scale. A 90°C treatment was set up in the return activated sludge loop. When keeping apparent sludge age at 15 days, 90°C treatment decreased sludge production by 30.4%. However, effluent quality was altered. A sludge minimization ASM1 based model was set up and calibrated against experimental dat...

This study assesses teh potential of activated carbon prepared from sewage sludge for nickel ions adsorption from aqueous solutions. Activated carbon physicochemical properties were determined. Batch adsorption experiments were performed as a function of pH solution, adsorbent dose, initial metal ions concentration, contact time and temperature. Teh experimental data were analyzed by teh La...

Activated sludge is widely used to treat municipal and industrial wastewater globally and the formation of activated sludge flocculates (flocs) underpins the ability to separate sludge from treated water. Despite the importance of activated sludge flocs to human civilization there have been precious few attempts to rationally design fit for purpose flocs using a bottom-up approach based on a so...

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 ...