Waste water treatment plant – Veliko Tarnovo

The construction of the WWTP in Veliko Tarnovo started in 1974. Today the WWTP serves approximately 60% of the population of the city.
The technological scheme of the main purification project (1974) provides mechanical, biological treatment and disinfection of water before discharge into the Yantra River, which here is a second grade water intake. Sludge generated in the treatment process is designed to decay under anaerobic conditions in a two-stage mesophilic heated digesters (the temperature of the decay is 33-35 degrees).
As a result of the opportunities provided by the mechanical dewatering of sludge we developed the project "Temporary technological scheme for the WWTP – Veliko Tarnovo with aerobic stabilization and mechanical dewatering of sludge” in 1994. The main elements of the scheme, providing treatment to all of the water entering the station (about 38,000 cubic meters per day) are the primary settling tanks, biological treatment with aerobic stabilization and subsequent mechanical dewatering of sludge. This was the first stage of reconstruction and modernization of the WWTP. The facilities under this project called ​​stage I have been completed and in operation since 2000. At the same time started the design of the stage II of the reconstruction and modernization of the waste water treatment plants. It includes reconstruction of existing facilities and construction of a new technological scheme of anaerobic digestion and mechanical dewatering. The funds amounting to 1,250,000 levs were provided by the Ministry of Environment and Water.
The WWTP currently works in accordance with the above technological scheme.
The obtained sludge is in a temporary depot near Resen.