2.5.2015

Biodiili Ltd has developed a new peat production method which is decreasing impacts of peat production on watercourses and environment.

There has been development work going on in Biodiili about new and better peat production method. As a result of this work new production method has been developed. The method is called Biofiksu® (Biosmart) also called BF-method and patent is pending for the method.

BF- method has many advantages compared traditional methods. By using the method, floods can be controlled, emissions to waterways decreased, dust problems minimized and GHG emissions decreased. Also small and shallow peat deposits can be utilized efficiently and the area restored quickly. And finally the investment and production costs of the method are low.

By using BF-method floods from heavy rains can be led in a controlled way to water cleaning systems. Remarkable part of the runoff water from peat production area can be evaporated, which decreases emissions to waterways. The nutrient load to waterways is high during production season. By using BF- method, closed water circulation during production season is possible, which eliminates nutrient emissions to lakes and rivers

The effectiveness of the method for flood control has been examined with mathematical simulation. The results from the constant flow measurements from the peat bogs of Vapo Group were used as initial values in the simulation. The measurements were executed by Metso Group and the results are published in their website (http://www.metso.com/fi/automation/publicwebreports.nsf/ReportFrontPages/EDA8EC557523CDE8C2257C240047401A?opendocument&lang=FI)

Results of the simulation from two different bogs are presented next. The chosen bogs, Mäkikylänsuo in Ähtäri and Okssuo in Tammela, had very different weather conditions. The simulation is made for the summer of 2013.

Picture 1. The simulated water flow to the overland flow field with the Biofiksu® –method in stage 1 in Mäkikylänsuo in Ähtäri Finland in the 2013.

The red line in the picture presents the designed flow rate of the overland flow field. From the picture it can be seen that the flow would have been optimal throughout the year except during the flood peak in the spring which results from the melting of snow. It can also be seen that there would have been no water coming out from the production area between the middle of June and the middle of September. This means that during this time there would have been an internal circulation of water in the area.

The control of runoff water with BF –method is getting better after a few years of peat production in the area. In picture 2 the situation after 4‒5 years of production is presented.

Picture 2. The simulated water flow to the overland flow field with the BF –method in stage 2 in Mäkikylänsuo in Ähtäri.

In the simulation in picture 2 the measurement results of 2013 were used. The red line presents the designed flow rate of the overland flow field. In this case the flood peak in the spring could have been fully controlled and the internal circulation (no water flow from the production area) would have lasted 5 months with the BF -method

The other example bog area, Okssuo in Tammela, had very little rain during the summer in 2013. The simulated flow from the area to the overland flow field using the BF –method in stage 1 is presented in picture 3.

Picture 3. The simulated flow to the overland flow field from Okssuo in Tammela using the BF-method in stage 1 according to the measurement results from the summer of 2013. The red line presents the design flow rate of the overland flow field.

From the picture it can be seen that there would have been no water flow to the overland flow field from the area during the year 2013. The internal circulation would have been achieved already in the beginning of the peat production and there would have been no water emissions from the area at all.

Because of the efficient control of the floods the overland flow field works with the best possible efficiency all the time. Furthermore, the enhanced evaporation of water in the area reduces the amount of water needed to conduct to the overland flow field. In the BF –method the production area acts as a part of the water cleansing system and the water that is conducted to the overland flow field is already purified which ensures that the water treatment system is working properly and efficiently. BF –method also reduces CO2 and dust emissions and fire hazard and accelerates the restoration of the area and also enhances the biodiversity in the area. The benefits are achieved without reducing the efficiency of peat production and with small investment and operation costs.

For further information contact Kari Mutka (first name.surname@biodiili.fi or +35840 0344964).

14.3.2015

A new recycling concept – Growing of short rotation coppice willow on closed landfill sites using substrate made from recycled materials and landfill percolation water for irrigation

The first project concerning the concept was executed in the summer of 2013. The concept was proven functional and it has very remarkable benefits. The project is being continued during the summer 2014. Biodiili Ltd provides the customer with tailored concept which is suitable for the specific situation of the customer and the necessary consultant and planning services related to the concept.

In the concept short rotation coppice (SRC) willow is being grown on top of a closed landfill site and the substrate is made from ash from power plants, compost and excess soil materials. The percolation waters from the landfill can be used in irrigation of the SRC willow. Willow uses nutrients from the percolation waters and the substrate layer. Willow also evaporates percolation water used for irrigation. Waste materials are being recycled and the percolation water is not needed to conduct to a water treatment plant.

The growing of willow on closed landfill sites has been researched already since the 1980’s. However the growing conditions on the landfill sites were very different at that time compared today because the landfill sites didn’t have the same regulation than today. The willow was grown in a 20‒30 cm thick layer of sand, moraine or bark. The landfill also didn’t have water insulation, growth layers or gas recovery systems. For these reasons the growing of willow succeeded very variedly for example because of poor growth layer, dehydration and gas leaks. Nevertheless in best cases really good growth results were achieved.

The usage of nutrients of the landfill percolation water in growing of willow has also been researched already since the 1980’s. According to the experiments willow grew well in some cases and the growth was not disturbed by the intensive fertilizing or the harmful substances. Because there were no water insulation on top of the landfill area, the water used for irrigation could infiltrate into the waste layer. The method did not become common mainly because it was not profitable in the conditions at the time.

Nowadays the situation in Finland is different than in the 1980’s and 90’s in many ways: the amount of landfill sites has decreased, environmental and building regulations are more strict, tax has to be paid for landfilling of ash, the goals set for recycling are higher and there are restrictions concerning the landfilling of waste. Landfill gas is being collected. Landfills have gas collection layer, drying layer and growth layer. This means that the conditions to grow willow and use the percolation water irrigation are much better now than in the 1980’s and 90’s. In addition there are new goals for usage of renewable energy in Finland and in the EU, which has increased the profitability of growing willow. The usage of waste materials (ash, compost) as a substrate for willow and the use of nutrients from the percolation water offer a new way to increase the recycling rate and save costs significantly.

There are certain challenges concerning the concept such as: planning the right recipe for the substrate, planning the irrigation system, prevention of weeds and harmful animals and the harvesting of the willow without damaging the landfill structure.

Biodiili Ltd masters the whole production chain from the planning of the substrate formula all the way to the incineration of the willow.

For further information contact Kari Mutka (first name.surname@biodiili.fi, +35840 0344964)