|Monday, 09 January 2012 11:22|
Finland is taking a lead in renewable energy generation through innovation and smart recycling as demonstrated by three initiatives we highlight below.
Stora Enso to build innovative lignin extraction plant in Finland
LignoBoost system increases pulp mill capacity and replaces fossil fuels in lime kilns.
Finland’s Ministry of Employment and the Economy has granted energy support worth EUR 4 million for a plant demonstrating the innovative LignoBoost lignin extraction system at Stora's Sunila pulp mill located in Kotka, southern Finland. Lignin can be used to replace fossil fuels in lime kilns and increase pulp mill capacity more cost-efficiently than traditional technology. The new plant would be largest of its kind in Europe.
Lignin, a component of wood, will be extracted from pulp mill black liquor using the LignoBoost system patented by the Finnish company Metso, after which it is dried, enabling pulverized combustion. The dried lignin could replace 90% of the natural gas currently used as an energy source by Sunila mill’s lime kiln, representing 172,000 MWh per year. This would reduce carbon dioxide emissions by an estimated 33,000 tons per year.
According to Metso, when a recovery boiler is the limiting factor to increasing pulping capacity, LignoBoost is a good solution to the problem. If 25% of the lignin in the black liquor is removed, boiler capacity can be increased to enable 20-25% more pulp production. Metso believes that as the technology becomes commercialized, LignoBoost could be sold to many factories worldwide. One plant has already been sold to the United States.
New forest chips and biogas plants to open in western Finland
New eco-efficient plants in Raahe and Kokkola will help produce electricity from forest chips and sludge.
Finland's Ministry of Employment and the Economy has given an energy support grant of EUR 3.98 million to Sievin Biohake Oy for the construction of a large-scale forest chips drying plant in Raahe, western Finland. The plant is expected to be completed by the end of 2013.
The plant will dry forest chips by using 10-20 MW of excess heat from Rautaruukki's factories in Raahe. The investment includes reception facilities and equipment for the raw material, chipping and crushing equipment, the drying plant, and storage for the dried chips. According to the ministry, Raahe's forest chip project could be a model for other areas with heavy industries that produce excess heat and which have substantial local forest resources.
The plant will produce about 200,000 solid cubic metres of chips annually which represents 400 GWh of energy. The plant will reduce the water content of the chips from about 50% to 20%. The raw material will be procured from local sources. There are several advantages to drying the forest chips. Dried chips can be stored for longer periods, they produce more energy, and can also be used to improve lower quality fuels.
The Ministry of Employment and the Economy is also giving an energy support grant of EUR 1.92 million to Pohjanmaan Biokaasu – Österbottens Biogas Oy for the construction of a biogas plant in Kokkola, western Finland. The plant will be located in the immediate vicinity of the wastewater treatment plant of Kokkola's Ykspihlaja port and industrial area.
The plant will produce 1.2 million cubic metres of biogas annually by processing wastewater treatment sludge, raw sludge and septic tank sludge, as well as biosludge from region's potato and animal feed producers. The gas can be used to produce about 2800 MWh of electricity and about 3000 MWh of heat per year. The plant is expected to be in commercial use by October 2012.
Innovative district heating plant to be constructed in Tampere, Finland
Pressurized combustion of pulverized pellets will make the plant more adjustable.
A new 25MW district heating plant using wood pellets as fuel will be constructed in the city of Tampere in central Finland. Finland's Ministry of Employment and the Economy has granted energy support worth EUR 1.42 million to Tampereen Energiantuotanto Oy for the construction of the plant. The new plant will cost EUR 8.2 million in total.
The project utilises different technologies in a new way. The pellets are pulverized with separate grinding machines which enables pressurized combustion and significantly improves the adjustability of the equipment in terms of speed and range compared to the commonly used furnace bed, fluidized bed combustion and circulating fluidized bed technology. Tampereen Energiatuontanto's objective is to create a working district heating plant concept for plants in the 20 - 40 MW range.
The new plant will reduce the use of oil and natural gas, and cut carbon dioxide emissions by about 6700 tons annually.