Experience of Operation of Facilities of Wastewater Biological Treatment for Nitrogen and Phosphorus Compounds

Summary

Introduction of technologies of wastewater treatment for nitrogen and phosphorus compounds is a priority way of development and reconstruction of treatment facilities of the MSUE Mosvodokanal. The technology of acidification of raw sludge of primary sedimentation plants makes it possible to increase the concentration of readily oxidizable organic compounds in wastewater which are necessary for organization of the process of advanced biological removal of phosphorus. Acidification of primary sludge of wastewater was introduced on industrial scale at the Lyubertsy treatment facilities of Moscow in 2009; it makes it possible to ensure the high quality of water treated at the block of biogenic elements removal of total capacity of 500 000 m³/day.

Key words

wastewater , biological treatment , biological removal of nitrogen and phosphorus , acidification

Perspectives of Introduction of Membrane Technique at Treatment Facilities of Moscow

Symmary

Studies of the membrane technique of treatment of low-concentrated municipal wastewater at a pilot unit of up to 5 m3/day capacity have been carried out. As a result, high quality of treated water concerning suspended particles and biogenic elements has been obtained, resistance to volley entries of industrial wastewater and high efficiency of water disinfection have been reached. Results of pilot tests have made it possible to appreciate the membrane biotechnologies as perspective for realization at Moscow treatment facilities. Advantages of the technology with the use of membrane bioreactors: considerable reduction in volumes of facilities and spaces occupied by them owing to the high concentration of activated sludge, possibility of a higher load per a volume unit and also significant decrease in quantity of excessive activated sludge. Membrane bioreactor technologies are one of the perspectives of development of treatment facilities under the conditions of limited areas.

Key words

wastewater , bioreactor , hydraulic condition , biological removal of nitrogen and phosphorus , membrane module

Development of basic process solutions for the reconstruction
of wastewater treatment facilities in Novosibirsk

Summary

An example of process solutions for the reconstruction of existing wastewater treatment plants using increased concentration of activated sludge and acidification of primary sludge is given. It has been shown that achieving the required effluent quality (N–NH₄ = 1 mg/l, N–NO₃ = 9 mg/l, N–NO₂ = 0.1 mg/l, Р–РО₄ = 0.7 mg/l) during the reconstruction of the facilities, the implementation of nitrogen and phosphorus removal processes in existing aeration tanks, with the actual flow of incoming wastewater, is possible by increasing the concentration of activated sludge in the aeration tanks to 5.2 g/l, which requires the installation of tertiary treatment filters downstream sludge separation in the secondary settling tanks. The use of tertiary treatment facilities to remove suspended solids is determined in comparison with a more expensive construction of an additional biological treatment unit operating with medium doses of activated sludge. It is shown that the information and technical reference book ITS 10-2019 being a recommendation and not a mandatory document, allows for the use of filtration structures for effluent discharge into category B water bodies. The issues of the responsibility of the designers of basic process solutions for achieving the required effluent quality during the implementation of the project are considered for two cases: first – the main process solutions and the project is developed by one company; second – the main process solutions and the project are developed by different companies.

Key words

wastewater treatment , designing , best available techniques , biological removal of nitrogen and phosphorus , acidification , public wastewater disposal system , aeration tanks , reconstruction of wastewater treatment facilities