Biological wastewater treatment using regenerated immobilized sludge

Abstract

The purpose of this work is to study biological wastewater treatment using air regeneration of immobilized sludge in an aerotank-bioreactor. For the experiment, physical modeling of gas- hydrodynamic processes in aerated wastewater treatment plants was used. An experimental laboratory setup for studying the distribution of activated sludge and the oxidizing capacity of a bioreactor has been developed and installed. Methods for investigating water-air regeneration of synthetic inert loading in a physical model of a bioreactor are described. To determine the concentration of free-floating sludge in the bioreactor, a calibration graph method was used, i.e. the dependence of the concentration of free-floating sludge on the intensity of light passing through the water-sludge mixture was constructed. The kinetics of biological treatment was studied by BOD and oxygen dissolved in wastewater in the presence of two biocenoses of sludge adsorbed on an inert ruff load and floating in a bioreactor. The method of processing the experimental data obtained using luxmeters using a calibration graph allows one to obtain the values of the concentration of free- floating and immobilized sludge in dynamics. It is shown that the periodic regeneration (renewal) of the immobilized sludge makes it possible to increase the rate and depth of wastewater treatment.