Tallinna Vesi is improving the biological treatment of wastewater
Tallinna Vesi will invest nearly €9 million over the next three years to improve the biological wastewater treatment process. This will increase the efficiency of nitrogen and phosphorus removal from the wastewater treated at Paljassaare Wastewater Treatment Plant, ensuring that the water returned to the environment is of the highest purity.
“The changes to be made by through this investment are important for maintaining and improving the environmental status of the Baltic Sea with a view to future needs. We have to bear in mind that the volume of wastewater from Tallinn and its surrounding areas is very large — every year, we treat 50 million cubic metres of wastewater," explained Aleksandr Timofejev, CEO of Tallinna Vesi. “This investment of nearly €9 million is targeted at improving the efficiency of biological treatment. The Paljassaare wastewater treatment plant can only operate at full efficiency if all stages of the treatment process — mechanical, chemical and biological — are running successfully," noted Timofejev.
The project is part of Tallinna Vesi's investment programme and aims to reconstruct the 12 secondary clarifiers of the biological treatment system at the Paljassaare wastewater treatment plant, which separate activated sludge from wastewater. Each secondary clarifier is 40 metres in diameter and 4 metres deep.
According to Timofejev, the reconstruction will improve the continuity of the biological treatment process, increase its optimisation potential and make the system more flexible and stable. The reconstruction works on secondary clarifiers will include the renovation of the reinforced concrete structures and upgrading of the technological equipment, putting in place new electrical installations, upgrading of the metering systems and adding automatic control functionalities.
Throughout the long construction period, the operation of the treatment plant will be arranged in such a way as to ensure that the high performance of the treatment process is guaranteed at all times.
The project will be carried out by RVT Ehitus OÜ and OÜ Mapri Ehitus with the due date for completion in 2027.
“The secondary clarifiers are a very important step of the wastewater treatment. Modern technology and advanced equipment help to meet the ever more challenging environmental targets and ensure more energy-efficient wastewater treatment. The reconstruction will extend the service life of the existing infrastructure without leaving a large environmental footprint as opposed to building an entirely new infrastructure," said Taavo Säärits, Member of the Board of RVT Ehitus OÜ.
At the Paljassaare plant, 130,000 m³ of wastewater is treated every day in three different treatment stages to turn it into effluent that meets all requirements. The final stage of treatment at the Paljassaare wastewater treatment plant includes the bio-filter — a technology that is the only one of its kind applied in the Baltic States.
Every year, about 650 tons of debris, 240 tons of grit, 12,000 tons of suspended solids, nearly 2,000 tons of nitrogen and about 250 tons of phosphorus are removed from wastewater at the Paljasaare wastewater treatment plant.
AS Tallinna Vesi is the largest water utility in Estonia, providing services to more than 24,900 private customers and businesses and 470,000 end consumers in Tallinn and its surrounding municipalities. Tallinna Vesi is listed on the main list of the Nasdaq Tallinn Stock Exchange. The largest shareholdings in the company are held by the City of Tallinn (55.06%) and the energy group Utilitas (20.36%). 24.58% of the company's shares are freely floating on the Nasdaq Tallinn Stock Exchange.
Additional information:
Kristiina Tamberg
AS Tallinna Vesi
Head of Communications and Marketing
372 52 855 21
