The activated sludge process is one of the most important parts of conventional wastewater treatment plants. Wastewater is treated biologically in activated sludge basins. Activated sludge can remove soluble contaminants, primarily organics compounds and nitrogen, from the wastewater stream. The activated sludge is a mixture of microorganisms, inorganic and organic compounds aggregated to flocs...

A model for the simulation of nitrification in activated sludge is presented and calculations are compared with experimental results from different sources. The role of protozoa and the influence of reactor type and of diurnal variations in flow and strength of the sewage are considered. Favorable conditions for nitrification are low rates of sludge wasting, high temperatures, plug-flow-type re...

Seeding of nitrifying bacteria into the activated sludge process was studied both theoretically and experimentally. A simple model was developed for prediction of the effects of seeding of nitrifying bacteria from a separate stage into the activated sludge process. The purpose of seeding is to improve the treatment results and the process stability as well as to decrease the volume requirements...

the aim of this study was to determine the feasibility of coupling an electrochemical process with a biological treatment in order to degrade phosmet, an organophosphorous pesticide. the absence of biodegradability of phosmet by pseudomonas fluorescens and activated sludge was verified in our operational conditions. so, a conventional biological treatment is not appropriate for phosmet polluted...

Producing crude palm oil (CPO) will have side effect on producing palm oil mill effluent (POME).  Besides of high COD /BOD contents, POME still contains high amount of nutrients (nitrogen, phosphor and mineral). Traditional treatment of palm oil mill effluent using facultative anaerobic method not fully eliminated COD and BOD into allowable limit. The objective of this research was to utilize p...

Activated sludge is a complex ecosystem constituted mainly of bacteria and protozoa. Filamentous bulking, a phenomenon when the filamentous organisms dominate the activated sludge is still a widespread problem in the operation of activated sludge processes. Image analysis offers promising perspectives for early detection of filamentous bulking because the morphology parameters of the activated ...

Simulation-based design and analysis of biotreatment systems depends to a great extent on the accuracy of the model parameters used. In many cases, site-specific parameter estimates are not available and parameter values recommended in the literature are adopted along with a measure of judgment to account for bioprocess uncertainty. To better quantify process certitude associated with this appr...

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...