Realization: 2011-2012
Number of PE: 27 500
Client: Municipal WWTP, LLC
Cost of electomechanical part: 1 295 486,– EUR

Reconstruction of the municipal WWTP Hlohovec was done within the years 2011-2012. The main goal of reconstruction was the intensification of biological treatment step with focus on removal of nutrients in accordance with European legislation. This was the main reason for the changes in technology of this plant that were implemented to ensure a required quality of effluent and sludge.

After the reconstruction, WWTP Hlohovec works as a mechanical- biological treatment plant with nutrients removal and with a chemical precipitation of phosphorus by ferric sulfate solution. Sludge management consists of aerobic stabilization of sludge and of its mechanical dewatering.

The mechanical step consists of a grit chamber, mechanical coarse screenings, mechanical fine screenings and an aerated horizontal-flow sand trap. Storm waters are relieved to recipient after the sand trap.

The biological step (7 600 m3) consists of pre-denitrification and nitrification sections. Phosphorus removal is provided by a chemical precipitation with ferric sulfate solution. The air for nitrification is delivered by rotary blowers in dependency of on line measurement of dissolved oxygen concentration. After the nitrification sections biologically treated water with activated sludge flows to radial secondary clarifiers for separation. From secondary clarifiers purified water flows to recipient.

The sludge management consists of two sludge thickeners, two aerobic stabilization tanks, homogenization tank and two belt presses for dewatering of stabilized sludge. The air for two stabilization tanks is delivered by rotary blowers as well.

The measurement and control of the main technological processes is ensured by an on-line measurement of ammonium nitrogen, nitrate nitrogen and dissolved oxygen directly in biological step and online measurement of phosphate phosphorus at the outlet of the WWTP.