Browsing by Subject "Keestrack"

This research is for UPM Kymmene Oyj. They are very interested in this topic because they are Finlands biggest users of the stumps and also big stump dealer for the other companies. The research is included to the big research project which is coordinated by FIBIC. Projects name is BEST, which means Sustainable Bioenergy Solutions for Tomorrow. The European Union has set the obligations for the renewable energy source usage in their climate and energy policy. This means that the use of forest biomass needs to grow from year 2006 to year 2020 from 3,6 million cubic meters to 13,5 million cubic meters in year 2020. In the year 2012 usage of forest biomass was 8,3 million cubic meters. The share of the stumps from that amount was 1,1 million cubic meters. The share of the stumps can grow even more. If we are going to use stumps even more we should increase the quality of stump wood. Most harmful things in stump wood quality is the soil particles. They comes up from the ground with stumps when the stumps are lifted. These particles increases stumps ash contents which is very harmful in the combustion process. But still stumps are energy rich fuel which keeps low moisture content during the winter and that is the time when we most need energy. The goal of the research is to find ways to rise energy thickness of the stump by different handling methods. First method is to precrush stumps with Arjes Raptor XL crusher. That special method should decrease moisture content and this has founded out earlier in practical tests because this crusher has special crushing unit. Second method is to take unwanted particles away by sieving. In the research we use two different sieving machines: Neuenhauser 2F StarScreen starscreen and Keestrack Frontier screen. Crushing and sieving together increased heating values 7,5–16,6 % and average was 11,1 %. Different handling methods effects most by decreasing moisture and ash content.