Friday, December 14, 2012

PURE partners learning about wastewater treatment in Turku

For the last event of PURE project its partners have been invited to Turku on December 11th to visit Kakola wastewater treatment plant and the biogas plant of Biovakka.

This modern and the third biggest in Finland WWTP has its facilities built-in the rock of Kakola hill. The construction was completed in 2008, and now plant is serving the population of 300 000 inhabitants in the Turku region. Despite being pretty costly investment for the city, it replaced five existing plants. Kakola WWTP allows more efficient effluent treatment, and due to this discharge to the sea is reduced by 30-50 %.  The heat energy of the sewage water is transferred into distant heating energy (18 MW) and distant cooling energy (35 MW) in a special thermal pump owned by Turku Energy Ltd. During the excursion, PURE project specialists from Poland, Latvia, Estonia and Germany traveled through the treatment process had an opportunity to exchange ideas and discuss experiences with Kakola engineers.

Later the group visited Biovakka’s Topinoja plant on Turku landfill, where the wastewater treatment sludge is treated and processed into biogas. This plant receives from Kakkola WWTP approximately 60 000-80 000 tonnes of sludge annually, which is undergone hygienisation (by heating the biomass in order to remove seeds and pathogens), anaerobic digestion (carried out in a completely closed and oxygen-free space), conversion of anaerobic digestion residues into recycled nutrients, biogas desulphurisation and storage. Later biogas is used as an environmentally friendly source of heat and electricity. Biovakka is also responsible for the final deposition of recycled nutrients generated in the process, and plans on producing biofuel in the near future.

Picture: scheme of Kakola WWTP

Author: Olena Zinchuk

Friday, December 07, 2012

PRESTO project seminar on sustainable sludge management in Daugavpils, Latvia

More than 80 representatives of wastewater sector in the Baltic Sea Region gathered to discuss sustainable solutions for sludge management on the “Sustainable sludge management” seminar on 23 – 24 October 2012 in Daugavpils, Latvia.

Waste to resource approach has to be applied to sludge management in order to follow the principles of sustainable development. With sewage sludge this is a great challenge all over the world as it contains well recognized contaminants such as heavy metals, pathogens and poorly biodegradable trace organic compounds. At the same time, sludge is rich in nutrients (N & P) and contains valuable organic matter that is useful when soils are depleted or subject to erosion and can be used in renewable energy production.  

“Digestion of municipal sludge is an efficient way to reduce emission of greenhouse gases and produce renewable energy” said in his presentation Jukka Lehtovuori from Kemira Ltd.

Seminar addressed technical aspects of sludge treatment including latest trends, practical solutions as well as safe sludge reuse and disposal alternatives. During the site visit to the hosting waste water treatment plant of Daugavpils udens Ltd. the participants had a chance to familiarize themselves with the lately modernized post-soviet waste water treatment plant and hear about the reconstructions that have been done to improve the nutrient removal and sludge handling.

“Thanks to the investments already finalized within PRESTO project, we have now well-equipped workstation for testing samples of wastewater and sludge” said Aleksandra Vasiljeva from Daugavpils udens Ltd.

The seminar continued next day in Kaunas, Lithuania, with Laboratory Clinique, an interactive learning session for laboratory practitioners, led by Technical University of Berlin.

New fume cupboard purchased within PRESTO project

Old fume cupboard
Text by: Agnieszka Ilola, UBC Environmental Commission, Project Officer, PRESTO Project