station drawing from the northeast side
Sketch of the facade of the future wastewater treatment plant

Imatra received a grant of 1,1 million euros to improve the energy efficiency of the wastewater treatment plant

Release
12.1.2021 11:14
The grant will be used in connection with the construction of the new treatment plant starting in the spring.

The maximum amount of €1,1 million granted by the Ministry of the Environment will be mainly used for waste water heat recovery and for improving wastewater aeration.

- Heat recovery is a pretty big new thing. Of course, most of the heat is lost in the drains, but this is the best that can be done sensibly so far, says the water management manager of Imatra Vede Kari Pietarinen.

Another thing to be renewed with the grant is changing the wastewater aeration from surface aeration to bottom aeration. The latter is more efficient than the current surface aeration. 

- Most of the pumping station's energy consumption goes to pumping and aeration. Aeration has a larger share of these, Pietarinen explains.

In the renovation and expansion of the treatment plant, new facilities necessary for operation are built for the treatment plant; garage, compressor building and post-processing building. The total area of ​​these is about 600 square meters. Similarly, the cleaning process is enhanced. Despite this, the total energy consumption of the treatment plant will decrease during the renovation.

- According to a preliminary estimate, energy consumption would decrease by about 13 percent, but it is certainly not possible to know what kind of euro or energy amounts will be saved when there is no experience with the new technology yet. Time will tell the final benefit, Pietarinen reflects.

In the renovation of the wastewater treatment plant, which will start in the spring, all of the plant's technology will be renewed. During the renovation, the wastewater treatment basins and the process building remain the same. The old control room building will be demolished and a smaller new one will be built in its place.

The cost estimate for the wastewater treatment plant to be completed in 2023 is approximately 11 million euros.

 

More information Water supply manager Kari Pietarinen, kari.pietarinenatimatra.fi (kari[dot]pietarinen[at]imatra[dot]fi), tel. 020 617 4399

Improving energy efficiency in connection with the new wastewater treatment plant

  • The current facility's total energy consumption (electricity+heat) has been approx. 1550 MWh/a (0,30 kWh/m3) in recent years as an average
  • The estimated total energy consumption (electricity+heat) of the new renovated plant is approx. 1300 MWh/a (0,26 kWh/m3)
  • The total energy consumption is reduced by approx. 250 MWh

Energy-saving measures during renovation and expansion

  • The energy efficiency of the aeration of the activated sludge process is improved
  • Changing the current heat source, i.e. oil boilers, to renewable heat recovery of purified wastewater with heat pumps
  • The ventilation and heat recovery of existing buildings will be enhanced
  • The thermal insulation of the outer envelope of existing buildings will be improved
  • Adding a solar power system
  • Let's improve the energy efficiency of the current lighting