bbk 000000

UDC 628.356:661.63

KOZLOV M. N., KAZAKOVA E. A., Kharkina O. V., Dorofeev A. G., Nikolaev A. V.

A New Factor of Control of Facilities for Biological Removal of Phosphates from Wastewater

Summary

A new technological indicator making it possible to improve the efficiency and stability of phosphates removal at the facilities of biological treatment of wastewater for biogenic elements – the periodicity of change of phosphates concentration in the end of the anaerobic technological zone – is described. The use of this indicator reflecting the activity of phosphate accumulating bacteria has been assumed as a basis of a new algorithm of control of treatment facilities using the technology of biogenic elements removal and led to improvement of the efficiency of phosphates removal by 1,5–1,7 times.

Key words

biological treatment , aeration tank , efficiency , stability , concentration of phosphates , anaerobic zone , phosphate accumulating bacteria

DOI 10.35776/VST.2022.09.04
UDC 628.35

Kevbrina M. V., Dorofeev A. G., Agarev Anton

Comparison of the results of calculating aeration tanks according to different methods (for discussion)

Summary

The calculation results are compared according to the method described in the book by D. A. Danilovich and A. N. Epov «Calculation and technological design of processes and facilities for the removal of nitrogen and phosphorus from municipal wastewater», and the method given in the book «Wastewater technology. Processing and recovery of resources» (fifth edition, Metcalf & Addy), in a model unit, for which earlier in the article by V. N. Shvetsov, S. V. Stepanov and O. V. Khar’kina «Comparison of the calculation results for aeration tanks using the NII VODGEO/SamGTU and ASM2d models» calculations had been made according to the method of NII VODGEO/SamGTU and following the model developed by ASM2d. It is shown that calculations based on the equations of enzymatic kinetics and microbial growth (NII VODGEO/SamGTU, ASM2d and Metcalf & Addy) give similar results in terms of the volume of aeration tanks with the «tabular» method based on the German standard ATV-DVWK-A131E and revised taking into account the growth kinetics of nitrifying microorganisms. The difference in approaches gives different results as for the age of activated sludge; however, the final results of the volumes of aeration tanks and zones in them have discrepancies that do not exceed 15–20%. Simulation of the operation of aeration tanks in BioWin-3 program, designed on ASDM model that is essentially close to the ASM group of activated sludge models, with zone volumes calculated using different methods, showed a similar calculated quality of effluent. This confirms the possibility of any of the considered methods to adequately calculate the volumes of aeration tanks. The choice of the calculation method for each specific case depends on the availability and ease of use of the methodology, as well as on the personal preferences of the designer.

Key words

nitrification , denitrification , aeration tank , wastewater biological treatment , anaerobic zone , theoretical and empirical mathematical models , comparative calculation of the biological treatment facilities , technological calculation methods , anoxic zone