Impact of Conditioning Substances and Filtration Pressure on Dewatering Efficiency of Sewage Sludge

Sludge dewatering is a key element in sludge’s processing and management. Solid-phase separation, sludge volume reduction and the separation of a high-quality supernatant are the main tasks of the dewatering devices. The effectiveness of this task, in turn, results from the selection of the dewatering method and conditioning of the sludge before dewatering. The aim of the research was to determine the influence of conditioning substances (polyelectrolyte, fly ash and zeolite) on the efficiency of dewatering at variable filtration pressure. The use of polyelectrolyte in sludge conditioning was a solution that increased the efficiency of the filtration process. On the contrary, the use of structure-forming substances (fly ash and zeolite) slows the process but reduces the hydration of the filter cake. The same trends were obtained in dual conditioning combining dosing of polyelectrolyte and ash or zeolite. It was also shown that the dewatering efficiency of conditioned sludge with these two different substances (ash and zeolite) was the same. The use of zeolite in independent or dual conditioning was important for the quality of the supernatant.

Unsteady filtration under maximal draw-off velocities of Tupolang water reservoir

The article presents the results of field studies to determine unsteady filtration in Tupolang dam core. Calculations are carried out for phreatic line curve in the core of Tupolang dam under unsteady filtration for various velocities of reservoir draw-off and water yield coefficient. At the same time it has been established that the increase of velocity and time of water reservoir draw-off leads to the increase of filtration pressure, and the decrease of water yield factor leads to the decrease of filtration pressure. The increase of filtration pressure, in turn, contributes to the increase of the intensity of unsteady filtration of Tupolang dam core.

Influence of speed of filling and draw-off to the filtration regime of Earth-fill dam

To use and manage water resources and carry out protection measures from the destructive effect of water flow, water reservoir hydrosystem construction has greatly developed. The article presents the results of field studies to determine unsteady filtration in the Earth-fill dam core. In the research process, static data from literature review, field study data, and theoretical processing of research results were used. Numerical data processing was carried out with methods of mathematical statistics, and the graphical part was done using Microsoft Excel. Calculations were carried out for phreatic line curve in the core of Earth-fill dam under unsteady filtration for various velocities of reservoir draw-off and water yield coefficient. At the same time, it has been established that the increase of velocity and time of water reservoir draw-off leads to the increase of filtration pressure, and the decrease of water yield factor leads to the decrease of filtration pressure. The increase of filtration pressure, in turn, contributes to the increase of the intensity of unsteady filtration of the Earth-fill dam core.