STUDYING SPECIES COMPOSITION OF MICROORGANISMS PERFORMING WASTEWATER TREATMENT

Abstract

The relevance. One of the most effective methods of wastewater treatment is the biochemical one, which makes it possible to remove almost completely various dissolved organic substances from wastewater. To improve the oxidative power of aeration tanks and control the biochemical process of wastewater treatment, it was necessary to determine experimentally the variability of the biocenosis under the influence of the environment and other factors. The main aim of the research is to intensify biological wastewater treatment by means of direct effect upon the metabolism of activated sludge microorganisms Objects: species and quantitative composition of microorganisms as a result of treatment of domestic wastewater in aeration tanks; structure and composition of enzymes formed at purification. Methods: research of biocenosis, methods of hydrobiological control of activated sludge and microscopy of activated sludge. During microscopy of activated sludge, the functional state of organisms, especially indicator ones, is determined, organisms are counted by one or another method of quantitative accounting, they are classified by indicator groups, then the type of biocenosis and its characteristic features are determined. To study microorganisms of activated sludge using microscopy, the method of «live» drops under a coverslip is used. Results. Based on the carried out research it was identified that the removal of ammonium nitrogen and phosphorus pollution to standard allowable value in continuous-flow aerotanks without anaerobic zones is unattainable. Organic matters in aquatic medium oppress nitrifying bacteria development, therefore nitrification begins only after oxidation of carboniferous organic compounds under the conditions of the first stage of nitrification. Nitrobacteria are also capable to accumulate polyphosphates in their cells. Normally, considering superficial nitrification and phosphates demand of bacteria, biological treatment removes from 10 to 30 % of the dissolved phosphorus compounds. For developing nitrobacteria in retrofit designed aerotanks, it is possible to apply the attached microflora by means of various loadings and creation of anaerobic zones in one of the corridors, with the mixer and recycling of sludge mix in the construction head. The research of activated sludge biocenosis on its development stages helps determine the dominating forms of organisms in aerotanks working with different sludge loads. Smooth aerotank operating in activated sludge allows the constant biocenosis corresponding to a particular developmental stage. Biocenosis change demonstrates the change of aerotank operating mode.

Keywords

• activated sludge
• sewage flow rate
• aerotanks
• water treatment intensification
• microorganisms
• biocenosis