The presented research concerned the phenomenon of polyelectrolyte changes resulting from modification by applying the ultrasonic field. The main aim of this research was to determine the activation degree of this macromolecular chemical compound and its effect on sewage sludge subjected to conditioning and followed by dewatering. The overall goal was to investigate the potential way of reducing the dosage of chemical compounds prior to sewage sludge conditioning. The polyelectrolyte samples were sonicated with the ultrasonic disintegrator UD-20 coupled with a sandwich concentrator. The power output of the generator was 180 W and the ultrasonic field frequency was 22 kHz. To describe the geometrical characteristics of the separated phases, the following parameters were determined: surface area (A_A), perimeter (L_A) and non-dimensional coefficient. With reference to the obtained results, the most significant quantitative changes in shape and size of the separated phases were observed for the ultrasonic field exposure time in the range of 0 to 10 s. This was in agreement with the results observed during dewatering of the investigated sewage sludge. In view of the quantitative analysis of the structure of the polyelectrolyte subjected to the ultrasonic modification, dewatering of sewage sludge was considerably improved by the application of the presented method.

Adsorption is one of the basic surface phenomena involving saturation of the adsorbent surface with adsorbate molecules located near the adsorbent-adsorbate interface. The processes that are accompanied by the accumulation of adsorbate molecules on the surface are different from absorption, which...