On the basis of experiments carried out using an image analysis system and static zone settlement, the alum sludge floc structure and the floc packing status with varied polymer dosages were examined in greater detail to reveal the link with the settling behaviour manifested in the “CML30 method”. The results of image analysis lead to the findings of the floc size with a pattern in initially gr...

Various half-scale and lab-scale investigations have already shown that the disintegration of excess sludge is a possible pre-treatment to optimise anaerobic digestion. To verify these results, different methods of disintegration were investigated at a full-scale plant. Two stirred ball mills, a plant for oxidation with ozone, a lysate centrifuge and an ultrasonic homogeniser were applied. A po...

The treatment and disposal of excess sludge has been a rising challenge for wastewater treatment plants worldwide. In this study, simultaneous sludge reduction and nutrient removal was evaluated in laboratory scale sequencing batch reactors (SBRs). Two SBRs were operated alongside for a duration of 370d. One SBR was operated to achieve nutrient removal (control-SBR) at 10d solids retention time...

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...

Excess sludge treatment is indispensable in sewage plants. This study aims to reduce the excess material from activated and establish a mathematical model. Sludge dissolution rates were calculated by measuring total chemical oxygen demand (TCOD) soluble COD (SCOD) with regard water quality before after pretreatment. Then, reduction effects obtained means of suspended solid (SS) changes. The maj...

This paper aimed at analysing the current state of methods increasing methane generation during treatment organic sewage sludge. The authors considered theoretical principles biogas production and main directions intensification fermentation processes. A chemical study sediments produced plants in city Kharkiv, Ukraine, showed that C/N ratio investigated excess activated sludge is 4–5, mixture ...