Sludge formation in the activated sludge process with a sludge disintegration unit

The Intensification of Sewage Sludge Anaerobic Digestion by Partial Disintegration of Surplus Activated Sludge and Foam

Large quantities of sludge are produced in biological wastewater treatment. Sludge has a high putrescibility and therefore has to be stabilizsed in order to enable an environmentally safe utilization or disposal. The anaerobic digestion is the standard technique to stabilize the sludge. Digestion produces biogas and reduces the amount of organic matter. The amount of excess sludge production fr...

Modelling of the ultrasonic disintegration of activated sludge

Ultrasonic treatment of waste activated sludge is one of the possibilities to reduce excess sludge production through the mechanism of sludge disintegration and cell lysis. In the past, several attempts have been made to model the process of solubilisation of the particulate volatile suspended solid part of the activated sludge (VSS) into soluble COD (sCOD). However, the focus of these models w...

The Microbiology of Activated Sludge Process

Model for nitrification in activated sludge process.

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...

A Comparative Study of the Efficiency of Granular Activated Sludge and Common Activated Sludge in the Removal of Chromium (VI) from Synthetic Solutions

Introduction: Aerobic granules as a novel type of bio-sorbent have an excellent settling ability and high-porosity structure. This study investigated the feasibility of aerobic granules for chromium (VI) removal from synthetic aqueous solution and compare it with conventional activated sludge. Method: In this research the effect of some important parameters including pH (5, 7, and 9), initial c...