REGULAR RECYCLING OF WOOD ASH TO PREVENT WASTE PRODUCTION

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1 LAYMANS REPORT REGULAR RECYCLING OF WOOD ASH TO PREVENT WASTE PRODUCTION RecAsh - A Life-environment demonstration project - with contribution from the LIFE financial instrument of the European Community.

2 RecAsh improving recycling of wood ash to forest land Ash-recycling creates an ecocycle Introduction Logging residues (i.e. small trees, branches and tree tops) are suitable as biofuel. However, when these particularly nutrient-rich tree parts are harvested, important elements are lost from the forest ecosystem. Therefore in 1998, the Swedish Forest Agency starts to recommend that wood ash should be recycled to forest land from which logging residues have been or will be harvested. However, a survey four years later showed that wood ash recycling to such sites was still inadequate. The main factor preventing the practice from being more widely implemented appeared to be a lack of knowledge about ash recycling. In order to create better conditions for ash recycling, the Swedish Forest Agency took the initiative of applying for project funding from EU-Life. The application was submitted in September 2002 and funding was approved by the EU Commission in September The resulting project (the RecAsh project) ran from September 2003 to December The aim of the RecAsh project was to create favourable conditions for regular recycling of wood ash to forest land. Wood ash recycling complies with the Sixth EU Environmental Action Programme Environment 2010: Our Future, Our Choice - COM/2001/0031.

3 Loading of logging residues after regeneration felling. A stack of logging residues left to dry at a forest roadside. How to organise ash recycling Wood ash should meet three basic requirements: It should contain all the macronutrients present in the logging residues (except nitrogen, which is eliminated during combustion). It should not cause an accumulation of metals or any other harmful substance in the soil. For this reason, the ash should originate from the combustion of non-contaminated wood only. It should not cause direct harm when spread. To be suitable for application, the ash must first be processed in order to reduce the reactivity and solubility. Unprocessed ash is too reactive to be spread, as it can burn natural vegetation, especially mosses. If the ash is not processed, a rapid and harmful change in ph may also occur in nearby streams. There are currently three main methods for processing wood ash: Self-hardening and crushing. Compaction. Granulation. In all three processes, the ash is first wet with water to initiate chemical hardening, but the amount of water required and the procedures that Granualation is one method for processing wood ash. follow vary between the processes. When the ash has been properly processed, it can be spread either by ground spreader or helicopter. However, ground application is considerably more common due to the lower cost. Wood ash application should be thoroughly planned in advance. Suitable sites for spreading include thinned stands where the ash spreader can use existing access roads and clear-felled areas with established ground vegetation. The suitable ash dose must also be determined. The maximum dose allowed in Sweden is 3 tonnes of wood ash (dry weight) per hectare, while lower doses are recommended for less fertile soils. However, in Finland higher doses are used to increase tree growth on drained peatland.

4 sustainable way. Within the Swedish case study area, the harvest of logging residues during regeneration felling increased during the project period from 16 % (2002) to 38 % (2006) of the total regeneration felling area notified to the Swedish Forest Agency. In total, during the project period, according to the information provided by the notification forms, harvest of logging residues was performed on approximately hectares, corresponding to a energy value of m 3 of oil and tonnes of carbon dioxide from fossil origin. One of the reasons for ash recycling is to maintain natural chemistry in forest streams. Environmental benefits Forest ecosystems need wood ash The rain falling on parts of Europe is still acidic to a certain degree. This acidity causes the soil to lose important nutrients and buffering capacity. However, the harvest of forest biomass also removes nutrients and acid-buffering capacity from the ecosystem. The nutrient losses from a forest generally increase by a factor of 1.5 to 4 if logging residues are harvested after felling. As a result, the harvest of logging residues may significantly contribute to acidification of the soil. If this process goes too far, trout and other fish may disappear from neighbouring streams and lakes. The water quality of large lakes can be improved by liming. On the other hand, small streams usually continue to carry acid water to the lakes, since they are very difficult and costly to lime. However, the water quality of small streams in the forest landscape can be improved cost-effectively by treating the adjacent forest with wood ash, thereby returning important nutrients and acid buffering capacity to the soil. It has been estimated that the critical load for acidification is exceeded on almost 25 million ha of forest land in EU 25. Ash recycling is one important tool to counteract this effect. During the RecAsh project, ash recycling increased from zero tonnes in 2002 to 7500 tons in 2006 within the Swedish case study area and the amount is expected to increase. Mitigate climate change The general consensus is that global emissions of greenhouse gases must be reduced if we are to avoid climate change with severe consequences for life on earth. In order to reduce the dependence on fossil fuels, the EC objective is to increase the use of energy from renewable sources from 6 % to 12 % of total energy consumption by By recycling wood ash to the forest, logging residues can be used as biofuel in a Combustion of forest fuel reduces the use of fossil fuels and mitigate climate change.

5 Ash recycling reduces the deposition of ash in landfills. The picture above shows a chrucher breaking up selfhardened ash before spreading in forests. Less waste in landfill Wood ash belongs in the forest. Dumping high quality wood ash in landfill conflicts with public efforts to reduce the flow of waste to landfill. Wood ash recycling returns the nutrients in the trees to their place of origin, i.e. forest soil. The ecological effects of ash recycling on flora, fauna and tree growth and on water and soil chemistry have been thoroughly studied in recent decades. These studies show that pure, noncontaminated and stabilised wood ash can be used as a compensatory fertiliser on forest soils without any significant negative impact on the environment, provided that the ash is applied with consideration to sitespecific conditions. During the RecAsh project period, the amount of wood ash dumped in landfill decreased from tons to tonnes (i.e. from 60 to 35 % of total wood ash production) within the Swedish case study area. Economic benefits and employment opportunities Ash recycling benefits forest production The positive effect of wood ash on pine trees growing on nitrogen-rich peatland was first demonstrated by the Finnish Forest Research Institute in the 1930s. On these sites, 4 tonnes of ash (dry weight) per hectare generally increase tree growth by 2 to 4 m 3 per year. The effect is known to persist for at least 30 years, which is longer than the observed effect of artificial fertilisers. A positive effect of ash on forest production has also been found on medium to highly productive mineral soils in southern Sweden, where a dose of 2 tonnes of ash and 2 tonnes of dolomite lime per hectare has been found to increase tree growth by 14 % on average. With the RecAsh project, a total of about ha were treated with ash within Swedish case study area, where the annual average tree growth is 5 m 3. If tree growth were to be increased by the average 14% during a period of 30 years as a result of this ash

6 Ash spreading with helicopter in Finland. Photo Samueli Rinne. treatment, the increase in total production would be about m 3, corresponding to a value of at least 2 million Euros. Employment Experiences from Sweden suggest that the whole chain from harvesting logging residues at a regeneration felling site to the combustion process requires 0.18 man-years per 1000 MWh of energy obtained. However, this figure does not include any ash recycling. When the RecAsh project started, logging residues corresponding to approximately MWh were harvested within the case study, requiring about 72 man-years. At the end of the project the amount of logging residues had doubled, thus requiring an additional 72 man-years. Unfortunately, we do not have enough data yet to accurately determine the manpower demand in relation to ash recycling. However, by the end of the project, at least three people were working fulltime with ash recycling within the Swedish case study area. Considering that 7500 tonnes of ash were spread during 2006, 1000 tonnes of ash required 0.4 manyears. However, this is most likely an overestimate, since the practice was Forest fuel extraction and ash recycling creates new jobs in rural areas. still in its infancy. Encouragingly, an increased demand for forest fuels as well as an increased interest in wood ash recycling was recorded in Sweden during the project. For example, several biofuel companies advertised for new personnel to deal with ash recycling. The RecAsh project has contributed to this trend by promoting good practices for harvesting logging residues and providing systems for regular wood ash recycling. It also seems likely that when regular wood ash recycling systems start to operate at full scale in other regions, the increase in harvest of forest fuels will accelerate, creating further employment opportunities. At present, the harvest of logging residues corresponds to 7 to 9 TWh annually, but the Swedish Forest Agency anticipates this amount potentially could double within the coming 10 to 15 years. If so, this would mean that in Sweden alone, to man-years would be devoted to the handling of forest bio-fuels in the relatively near future.

7 Handbooks and demonstrations were two important tools to disseminate knowledge and good practices. Different tools to achieve the objective Case studies showed the way Two case studies were performed within the RecAsh project, one in Finland (North Karelia) and one in Sweden (Värmland/Örebro). These studies covered most aspects of wood ash recycling, including the development of systems for ash storage, production of processed ash products, ash product testing, transport, contacts with forest owner and authorities, spreading and documentation. Two reports have been produced, the Case Study Evaluation Report and the Case Study Documentation Report. These reports can be downloaded from Handbooks provided help and support Handbooks describing the techniques, regulations, costs and environmental benefits of wood ash recycling have been produced in Swedish, Finnish and English. The version in English is adapted to an international perspective and also includes a chapter about forest fuel extraction. These handbooks can be downloaded from Ash study added knowledge A Finnish study has determined how the metal and mineral content differs between wood ash particles The case-studies developed and tested complete systems for ash recycling. of different sizes. The results of this study will provide valuable input to work on future recommendations and the development of new techniques for wood ash processing. Field demonstrations exemplified good practice Field demonstrations of good practices for wood ash recycling were organised. At these events, a number of aspects relating to ash recycling were discussed. These included environmental benefits, recommendations concerning sampling, processing, storage and transport of ash, and the economic aspects of different techniques. In total, 13 demonstrations were held in Sweden and Finland and attended by 374 people.

8 Participants at the international seminar in Sweden. A RecAsh poster at an international bioenergy fair. Education removed obstacles To remove obstacles for wood ash recycling, 1398 people participated in courses on harvesting logging residues and ash recycling. The main target groups were personnel at the Swedish Forest Agency and other authorities, forest owners, wood fuel companies, energy producers, and entrepreneurs. These courses were highly appreciated by the participants, and the personnel at the Swedish Forest Agency who attended continue to inform and advise forest owners and different entrepreneurs about wood ash recycling. Free education material packages have been produced in Swedish, Finnish and English. These packages can be downloaded from Seminars gave deeper understanding RecAsh organised three national seminars, two in Sweden and one in Finland. These seminars discussed wood ash recycling in a broader perspective. Lectures were given by scientists, engineers and representatives from different authorities about techniques and the environmental background to ash recycling. Practical demonstrations of ash recycling were also organised in conjunction with these seminars. In total, 181 people participated. RecAsh brought ash recycling to Europe Two international seminars were organised within the project, one in Prague, Czech Republic and one in Karlstad, Sweden. In total, they were attended by 180 participants from 17 countries within the EU, as well as from Norway and Japan. A workshop held in Karlstad resulted in recommendations to policy makers and politicians within the EU. In conjunction with the seminars, field trips were arranged to illustrate acidification problems in the North Czech Republic and to demonstrate harvest of forest fuels and wood ash spreading in Karlstad. The experiences gathered within the project will allow systems for ash recycling to be adapted to regional conditions in other parts of Europe. Spreading the results An important task of the project was to spread the information obtained. In addition to the handbooks, demonstrations and seminars, the project website info has become an important tool in reaching stakeholders all over Europe. By the end of the project, more than hits had been recorded, with visitors representing all the countries in Europe. Leaflets, newsletters, posters and information folders have also been produced and distributed. In addition, the project has been publicised on television and radio and through at least 20 newspaper articles. An information video entitled From Forest Fuel Extraction to Ash Recycling has been produced and distributed to about 670 stakeholders. Copies of this video can be ordered through the website. Produced within RecAsh - a LIFE-enviroment demonstration project- with contribution from the LIFE financial instrument of the European Community.