Waste management in Oulu, the capital of northern Finland, recently entered a new era with the commissioning of two new facilities: Finland’s largest covered waste sorting centre and a waste-to-energy plant. Thanks to these new facilities, only 5-10% of local waste today now goes to a landfill.
Oulu Waste Management in northern Finland is responsible for managing waste treatment and coordinating wasterelated logistics in Oulu, and encouraging the over 290,000 people living in and around the city to become more waste-aware. Limiting the amount of waste people generate and promoting recycling and reuse is a key priority.
Oulu Waste Management’s Rusko waste management site is used by 300-350 customers a day and consists of a protected park area of 42 hectares, of which 5.5 hectares are used as a mixed waste and construction waste landfill. The remainder is used for reuse stations, including a free station for dropping off reusable domestic waste, hazardous waste storage, composting, and offices.
|Oulu Waste Management’s new Lare sorting centre is Finland’s largest sorting facility and the largest to be fully under cover. Photo: Harri Tarvainen
Biowaste is composted in specially designed composting drums, the output from which is used in local landscaping and construction work. Plastic and energy waste from local businesses is baled there too. Methane has been utilised for over 15 years and is either sent off-site for use in a local rock mineral wool factory, a laundry, and Oulu University Hospital or used on-site for heating purposes. Microturbines keep the site self-sufficient in electricity and surplus output is sold to the national grid.
Two major improvements
Waste management in Oulu recently saw two major developments, both of which were commissioned in mid-2012: a new sorting centre and a new waste-to-energy combined heat and power plant.
The new Lare sorting centre at Oulu Waste Management’s Rusko site is Finland’s largest sorting facility and the largest to be fully under cover. Extending over 3,600 square metres, the roof of the centre is currently covered by a mat of flowering stonecrop; the University of Helsinki has set up 20 test strips on the roof to identify possible alternatives for use here and elsewhere.
The sorting centre has been dimensioned to handle around 50,000 t/a of domestic and commercial mixed waste that does not go directly to the new Laanila waste-to-energy plant. The target is for around 25,000 tonnes of the mixed waste received to go to Laanila, 15,000 tonnes to go for recycling, while the remaining 10,000 tonnes not suitable for either will be sent to the site’s landfill.
Sorting is mainly handled by a mix of grab buckets and loaders, with some manual assistance, at the moment that is. The design of the building allows for the addition of sorting robots, crushers, sieves, and other equipment at a later date.
Significant improvement in local waste utilisation
Commissioned in August 2012, the 55 MW grate-fired Laanila plant is capable of handling 120,000 t/a of mixed waste, a significant proportion of the region’s combustible waste. The unit is already helping diversify the energy generating mix locally and making waste management in the Oulu region and further afield in northern and eastern Finland much more efficient.
|The new 55 MW waste-to-energy plant is capable of handling 120,000 t/a of mixed waste, a significant proportion of the region’s combustible waste.
Thanks to the new plant, the amount of waste arriving at the Rusko site will drop from 100,000 t/a to 40,000 t/a and methane emissions from the site will fall by nearly 90%. A large proportion of the plant’s output, in the form of steam, is utilised locally for industrial purposes. Electricity and district heat is also supplied to local residents, enough heat, in fact, for some 5,000 family houses.
Utilising waste in this way is in line with both national and EU waste management goals, and results in less greenhouse gases being released than if waste were sent to landfills, reduces the pressure to find new sites for landfills, and has helped lift waste utilisation levels significantly. It also reduces the odour-, fire risk-, and verminrelated problems typically associated with landfills.
Laanila’s annual CO2 emissions are estimated to be around 90,000 tonnes, or approx. 4% of Oulu’s total industrial emissions. This represents a very positive contribution to the local CO2 balance, as it reflects an estimated reduction of 149,000 tonnes of CO2 equivalent, thanks to the elimination of old peat-fired boilers and a reduction in landfill methane emissions.
Together, the new Lare sorting centre and the Laanila waste-to-energy plant have been key factors in ushering in a major improvement in waste management in Oulu and increasing the total waste utilisation rate locally to around 90%.
|Extending over 3,600 square metres, the roof of the sorting centre is covered by a mat of flowering stonecrop. Photo: Harri Tarvainen