Expansion and reconstruction of WWTP Zvolen

Expansion and reconstruction of WWTP Zvolen

Expansion and reconstruction of WWTP Zvolen

Date of completion: 2007

The original WWTP Zvolen had been built in 1971 and the capacity became insufficient over time.

The original technology had not been able to handle the higher demands of elimination of nutrients, along with systematic hydraulic and substance overloading. WWTP had not been able to meet the legislation demands for waste water treatment.

The new plant was designed as a mechanical and biological treatment plant with anaerobic stabilization of spare sludge and with use of biogas.

Biological treatment consists of an activation process with the elimination of nutrients (nitrification with pre-set denitrification and with biological elimination of phosphorus).

WWTP Zvolen is interesting by the fact that waste water flows in via two separate sewage pipes, each with its own pre-treatment that connect together in a sand and fat trap and then are again divided into two independent mechanical and biological lines - new one and the reconstructed old one.

The sludge treatment is made of mesophilic anaerobic stabilisation of sludge, followed by mechanical dewatering.

Gas treatment uses produced biogas in boilers and in the cogeneration unit.

The management of biological and chemical processes is supported by an installation of continual monitoring of:

  • oxygen concetration
  • amoniac nitrogen and phosphate concentration in the outlet of the WWTP,
  • insoluble substances in the spare sludge

An automatic system of management and monitoring of technological processes is installed at the Zvolen WWTP.

Čovspol ensured project documentation for realization of technological and electro technical part, and the realization of technological and electro technical part itself, developing of operation and manipulation manuals, start-up of the WWTP, managing and evaluating pilot tests.

TThe project of reconstructing and expanding the Zvolen WWTP (80 500 PE) was classified as project no.7 in the Strategy of the Slovak Republic, section Environment in the Indicative List of Project Proposals for ISPA 2001 in October 2000.
The cost of the entire construction was in the amount of 7 700 000 €.