waste water treatment in finland suvi holopainen

Waste Water Treatment Waste Water Treatment in Finland in Finland

Suvi HolopainenSuvi Holopainen

History of Waste Water History of Waste Water Treatment in FinlandTreatment in Finland

First wFirst waste waters were piped to water aste waters were piped to water systemsystem without purification. without purification. It lead to water pollution in water systems It lead to water pollution in water systems

close to cities.close to cities.

The first waste water plants were built in The first waste water plants were built in Lahti and Helsinki in 1910.Lahti and Helsinki in 1910.

History of Waste Water History of Waste Water Treatment in FinlandTreatment in Finland

In the 1920s and 1930s, sewers and waste In the 1920s and 1930s, sewers and waste water treatment plants were also built in smaller water treatment plants were also built in smaller cities.cities. However, only small part of waste waters was However, only small part of waste waters was treated those days and water pollution of water treated those days and water pollution of water systems close to cities was a big problemsystems close to cities was a big problem The pollution situation of water systems was the worst The pollution situation of water systems was the worst

at the beginning of the 1970s. at the beginning of the 1970s.

Mechanical waste water treatment plants were Mechanical waste water treatment plants were built in the 1960s but biological purification built in the 1960s but biological purification systems became more common in the 1980ssystems became more common in the 1980s

Waste Water Treatment in Finland Waste Water Treatment in Finland NowadaysNowadays

80% of inhabitants live within centralized 80% of inhabitants live within centralized sewerage system and waste water sewerage system and waste water treatment.treatment. In all population centres, waste waters are In all population centres, waste waters are

treated chemically and biologicallytreated chemically and biologically

Approximately 20% of the inhabitants live Approximately 20% of the inhabitants live in houses that are not connected to in houses that are not connected to centralized sewerage system centralized sewerage system

Waste Water Treatment in Urban Waste Water Treatment in Urban AreasAreas

There are approximately 550 waste water There are approximately 550 waste water purification plants in Finlandpurification plants in Finland

The most common method of purification The most common method of purification is biological-chemical simultaneous is biological-chemical simultaneous precipitationprecipitation


Steps of waste water treatment:Steps of waste water treatment: ScreeningScreening Separation of grease and sand Separation of grease and sand Preliminary settlingPreliminary settling Aeration Aeration Final sedimentationFinal sedimentation


Nitrogen removalNitrogen removal The most common method is biological The most common method is biological

process, which bases on nitrification and process, which bases on nitrification and denitrification. denitrification.

Phosporus removalPhosporus removal Chemical treatment is the most common Chemical treatment is the most common

method.method.

Waste Water Treatment in Waste Water Treatment in CommunitiesCommunities

SludgeSludge The treatment of the sludge constitutes 30% The treatment of the sludge constitutes 30%

of costs of waste water treatment plant.of costs of waste water treatment plant. Approximately 1 million cubic meters of Approximately 1 million cubic meters of

sludge forms in public waste water treatment sludge forms in public waste water treatment plantsplants in one year. in one year.

After treatment sludge can be used as After treatment sludge can be used as gardening and landscaping purposes.gardening and landscaping purposes.


Results:Results: 97% of organic matter of waste water and 97% of organic matter of waste water and

95% phosphorus was removed95% phosphorus was removed (2005). (2005). The biggest challenge will be the reduction of The biggest challenge will be the reduction of

nitrogennitrogen Nowadays, approximately approximately 54 % of Nowadays, approximately approximately 54 % of nitrogen can be removed.nitrogen can be removed.

Waste Water Treatment in Rural Waste Water Treatment in Rural AreasAreas

20% of Finnish inhabitants live in houses, 20% of Finnish inhabitants live in houses, which are not connected to the which are not connected to the centralized sewerage systemcentralized sewerage system Waste water treatment systems of those Waste water treatment systems of those

houses are often obsolete or otherwise houses are often obsolete or otherwise ineffectiveineffective

Waste Water Treatment in Rural Waste Water Treatment in Rural AreasAreas

Thanks to legislation, waste water treatment in Thanks to legislation, waste water treatment in rural areas will be improved notably over coming rural areas will be improved notably over coming years. years. According to the Decree, at least 90% of organic According to the Decree, at least 90% of organic

matter should be removed from waste water, as well matter should be removed from waste water, as well as over 85% of total phosphorus and over 40% of as over 85% of total phosphorus and over 40% of total nitrogen. total nitrogen.

The waste water systems of buildings that have been The waste water systems of buildings that have been completed before 2004 must fulfil new standards by completed before 2004 must fulfil new standards by 1.1. 2014 while the waste water systems of new 1.1. 2014 while the waste water systems of new buildings must fulfil those standards immediately. buildings must fulfil those standards immediately.

City of HelsinkiCity of Helsinki

HelsinkiHelsinki :: The capital city of FinlandThe capital city of Finland About 570 000 inhabitantsAbout 570 000 inhabitants Located on the coast of Located on the coast of

the Baltic Seathe Baltic Sea

All waste waters of All waste waters of Helsinki are treated in Helsinki are treated in one WWTP called one WWTP called Viikinmäki.Viikinmäki.

Viikinmäki Waste Water Treatment Viikinmäki Waste Water Treatment PlantPlant

Viikinmäki treats waste water of over one Viikinmäki treats waste water of over one million inhabitants.million inhabitants. All waste water from Helsinki and the runoff All waste water from Helsinki and the runoff

water from downtown area.water from downtown area. All waste waters of Järvenpää, Kerava, Sipoo All waste waters of Järvenpää, Kerava, Sipoo

and Tuusula.and Tuusula. Part of waste waters of Vantaa. Part of waste waters of Vantaa.

Viikinmäki Waste Water Treatment Viikinmäki Waste Water Treatment PlantPlant

Many benefits have been achieved by Many benefits have been achieved by concentrating waste water treatment on concentrating waste water treatment on one plant:one plant: Results of the treatment have improved. Results of the treatment have improved. Major economies have achieved. Major economies have achieved.

Waste Water treatment Process at Waste Water treatment Process at ViikinmäkiViikinmäki

Viikinmäki is a activated sludge plant. Viikinmäki is a activated sludge plant.

Waste water treatment consists of three Waste water treatment consists of three parts:parts: mechanicalmechanical chemical chemical biological purificationbiological purification

Waste Water treatment Process at Waste Water treatment Process at ViikinmäkiViikinmäki

Sludge Processing at ViikinmäkiSludge Processing at Viikinmäki

In thermal energy, Viikinmäki is totally self-In thermal energy, Viikinmäki is totally self-sufficient and about 50% self-sufficient in sufficient and about 50% self-sufficient in electricity. electricity. All that sludge is composted on the composting All that sludge is composted on the composting site called Metsäpirttisite called Metsäpirtti

ConclusionsConclusions

Public waste water treatment works rather Public waste water treatment works rather wellwell In future, the biggest challenge will be the In future, the biggest challenge will be the

reduction of nitrogenreduction of nitrogen

Waste water treatment in rural area has Waste water treatment in rural area has more problemsmore problems Situation will improve in the near future, Situation will improve in the near future,

thanks to legislation. thanks to legislation.

Thank you for your Thank you for your attentionattention

waste water treatment in finland suvi holopainen

Documents