ACTIVATED sludge processes are the dominating wastewater treatment method. Large quantities of hazardous excess sludge are generated in the processes, and elimination of the waste sludge has been a major problem for the last decade worldwide. The disposal of waste sludge is subject to various environmental, social and economic problems; and the cost consists about 50% of the operational cost of...

Sludge retention time (SRT) is an important factor affecting not only the performance of the nutrient removal and sludge characteristics, but also the production of secondary pollutants such as nitrous oxide (N2O) in biological nutrient removal (BNR) processes. Four laboratory-scale sequencing batch reactors (SBRs), namely, SBR5, SBR10, SBR20 and SBR40 with the SRT of 5 d, 10 d, 20 d and 40 d, ...

the present work has been performed to eliminate sewage dry sludge of alborze city wastewater treatment plant by using them as fine aggregate in concrete. on this basis, at first the selected dry sludge was analyzed for xrd and xrf for crystalline phases and chemical composition, respectively. the results showed that more than 50% of the sludge is formed of sio2 and it had more than 20% organic...

abstract one of the methods for improving soil physical quality of arid and semiarid regions is the application of cheap organic conditioners such as sewage sludge. this research was conducted in large pots (50 cm diameter, 25 cm height) to study the effects of tabriz petrochemical biological sludge at 4 rates (25, 50, 75 and 100 tons/ha) on organic carbon (oc), mean weight diameter (mwd) of ag...

The beverage industry has been a heavy producer of organic pollution. The major contaminants found in waste are biodegradable organic compounds, volatile organic compounds, toxic metals, and recalcitrant xenobiotics, suspend solids, nutrients (Nitrogen and Phosphor) Microbial pathogens and parasites. Activated sludge flocs contain a wide range of microorganisms such as bacteria, Fungi, yeast, v...