Review article

The article presents the study results of the performance of the experimental unit with a plastic film load working in a periodic mode of wastewater supply at high initial loads. The kinetics of the process and changes in the efficiency of wastewater treatment over time are considered. As it was revealed, an increase in the load on the bio-filter caused a corresponding increase in the rate of contaminants` removal over the entire range of tested loads, while biomass saturation with the substrate was not observed. This characterizes a high adaptive capacity of the attached biomass to high salvo loads. It is shown that the process of organic contaminants` removal on bio-filter under the conditions of periodic tests has a staged character, indicating the possibility of bio-filter operation in the modes of incomplete and complete biological treatment of wastewater, as well as for nitrification processes. The beginning of the nitrification process and its speed depended on the load on the bio-filter for organic pollution and the degree of wastewater treatment, and the change in the rate of nitrification was autocatalytic. An indicator of the non-oxidizable part of organic pollutants in wastewater is taken into consideration, which can be used in the evaluation of the bio-filter performance.