Excess sludge production is one of the limitations biological activated process. Therefore, study’s objective to upgrade MBBR process an integrated fixed film-activated (IFAS) reduce excess production. Two scenarios were followed in this study eliminate process: first, modifying moving bed biofilm reactor (MBBR) system by increasing solid retention time (SRT) from 5 15 days; and second, upgradi...

A new process which attains both excess sludge reduction and phosphorus recovery has been developed. In this paper, characteristics of sludge solubilization by ozone were investigated in batch experiments with sludge taken from an A/O reactor supplied with synthetic sewage and several real wastewater treatment plants. Then, performance of the new developed process was investigated in a laborato...

In order to study the performance and mechanisms of excess sludge reduction in the activated sludge that incorporates the Cannibal Process, laboratory activated sludge systems incorporating an anaerobic bioreactor into the sludge recycle stream were operated. In this study, the solids production in the Cannibal system was about 35-40% of the conventional system under steady state conditions. Th...

The Chebyshev finite difference method is applied to solve a system of two coupled nonlinear Lane-Emden differential equations arising in mathematical modelling of the excess sludge production from wastewater treatment plants. This method is based on a combination of the useful properties of Chebyshev polynomials approximation and finite difference method. The approach consists of reducing the ...

INTRODUCTION Down-flow hanging sponge (DHS) reactors employ polyurethane sponge media to retain biomass. Wastewater is trickled from the top of the reactor and purified by microorganisms within and on the surface of the sponge media as influent flows vertically downward through the reactor. Since the sponge media of DHS reactors are exposed to the atmosphere, oxygen dissolves continually into t...

The main objective of this work was anaerobic digestion of maize grains and maize silage and biogas production from these crops. Maize grains were treated using one-stage and two-stage anaerobic techniques; using hydrolysis and acidification as the first stage and methanogenesis as the second stage. Processing nonacidified maize grains in an anaerobic reactor is more stable, though the anaerobi...

The fermentation characteristics of activated biomass from two types of sludge, namely primary sludge (PS) and excess sludge (ES) were compared under three pH conditions (uncontrolled, 4, 10) over a period of 8 days. Results show the highest production of short-chain fatty acids (SCFAs) in PS and ES of 352 ± 7 and 324 ± 13 mg COD/g VSS, respectively at pH 10, on the 2 day in PS fermentation, an...