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- Anerud, Erik
(författare)
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An alternative supply system for stump biomass - coarse grinding combined with sieving of the produced hog fuel
- 2016
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Ingår i: International Journal of Forest Engineering. - : Informa UK Limited. - 1494-2119 .- 1913-2220. ; 27, s. 109-114
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Tidskriftsartikel (refereegranskat)abstract
- Transport costs are one of the major costs in the supply chain of stumps for fuel. Stump parts are bulkyand it is impossible to achieve full tonnages on trucks and trailers even though the load space iscompletely full. The transport economy for stumps is also negatively affected by the large amount ofcontaminants in the loads. Grinding the stumps at the landing and sieving of the produced hog fuel hasthe potential to increase load weights and reduce both the amount of contaminants and the transportcosts. To evaluate such a system a series of studies were made. Results show that coarse grinding andsieving reduced both moisture and ash content in the produced fuel, thus increasing the heating valueper ton delivered fuel and transforming a soil contaminated material to an acceptable fuel. Transportpayloads increased substantially compared to transports of stump parts, but a transport distance of110 km was needed before the coarse grinding system provided lower cost than the standard systemwith transports of stump parts and grinding at the heating plant. Further studies are needed to evaluatethe total energy efficiency in the two systems. Coarse grinding and sieving is a feasible way to increasefuel quality and improve transport economy. However, total costs will in most cases be higher than forthe loose stump system which renders the method preferable only in cases where the sieving processconverts a non-acceptable material into an acceptable fuel.
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| 3. |
- Anerud, Erik, et al.
(författare)
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Biopohjainen menetelmä hakeaumojen suojaamiseksi
- 2022
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Ingår i: Bioenergia. - 2814-4910.
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- Metsähakekasojen suojana käytetään yleisesti fossiilipohjaista muovia. Vaikka muovi onkin hyvä suojamateriaali ja hyvää polttoainetta, muovia ei voi polttaa hakkeen seassa lämpölaitoksissa. Muovin erottelusta aiheutuu ylimääräistä työtä ja osana arvoketjua siitä aiheutuu paitsi valmistuksen päästöjä myös jätettä ja kierrätyskustannuksia.
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| 7. |
- Anerud, Erik
(författare)
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Evaluation of an improved design for large-scale storage of wood chip and bark
- 2021
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Ingår i: Biomass and Bioenergy. - : Elsevier BV. - 0961-9534 .- 1873-2909. ; 154
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Tidskriftsartikel (refereegranskat)abstract
- A developed bioeconomy needs better storage methods for wood chips and forest industry by-products, since increasing demands for more assortments, more storage will be necessary Today, solutions for coping with storage-related problems, such as dry matter losses and risk of self-ignition, are based on separating assortments into smaller piles and avoiding large-scale long-term storage of chips. A safe and efficient storage solution is needed to enable wood chip production all year round and not be limited to just-in-time production during the cold heating season when there is a large demand. This might result in a more robust system with larger buffer capacities, a less stressful working environment for chipping and transport contractors, and a better yearly machine utilisation. This study evaluated storage outcomes for wood chips and bark when using an improved storage design that created assortment separation using concrete walls and a semipermeable sheet for cover. The new design enabled efficient area utilisation and increased fire safety. The storage outcome was also improved in terms of moisture content, dry matter losses and temperature development compared to conventional open-air piles.
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| 8. |
- Anerud, Erik, et al.
(författare)
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Evaluation of the performance of a three-dimensional vibrating test rig for cleaning stumps
- 2012
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Ingår i: Australian Journal of Agricultural Engineering. - 1836-943X. ; 3, s. 51-58
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Tidskriftsartikel (refereegranskat)abstract
- It has been shown that vibrating devices can successfully be used for separation and removal of unwanted/contaminant material, for both laboratory and full-scale industrial purposes. The presence of impurities on energy-rich softwood stumps is a major drawback when using stumps as fuel, since it leads to high ash content. Vibration methods can be an efficient approach to remove excess impurities and achieve acceptable ash content. Stumps are usually shaken in connection with harvesting and stored afterwards to facilitate the removal of contaminants. The required storage duration can lead to high dry matter losses and a faster and efficient cleaning method such as vibration is highly desirable. This study evaluated the performance of an adjustable three-dimensional vibrating test rig designed to assess the cleaning efficiency of vibration-based methods. Vibrating parameters such as acceleration amplitude, frequency and displacement of the test rig were determined for 12-24 mm distance between eccentric weight centre of mass and the rotating shaft of electric motors at rotation velocity 19.16-29.17 Hz. The acceleration amplitude ranged from 1.38 to 5.71 g. The parameters could be repeated irrespective of direction and number of vibration directions. The test rig was therefore considered to be a reliable tool for determining and evaluating the efficiency of vibration in removing contaminants from stumps.
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| 9. |
- Anerud, Erik, et al.
(författare)
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Fuel quality and dry matter losses of stored wood chips - Influence of cover material
- 2021
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Ingår i: Biomass and Bioenergy. - : Elsevier BV. - 0961-9534 .- 1873-2909. ; 150
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Tidskriftsartikel (refereegranskat)abstract
- Irregular seasonal demand from heat- and combined heat and power plants means that outdoor storage of forest fuels is an inevitable step in the forest fuel supply chain. Storage of fresh comminuted biomass render substantial dry matter and energy losses. Covering can protect wood chips from rewetting, leading to a higher net calorific value and lower dry matter losses, and thus increase the amount of available energy. This study examined the combined effect of covering material on fuel quality and the amount available energy from wood chips stored in a full-scale pile. The combined changes in fuel quality and dry matter loss reduced the amount of accessible energy by 9.8% in the uncovered part, by 5.6% when covered with water proof or light semi-permeable cover materials and by 1.0% when covered with a thicker semi permeable material. Fuel quality of wood chips can be improved by covering the piles during storage but the gain is affected by the type of cover material. Seasonal storage in properly covered chip piles facilitate an increased annual utilisation of chippers and chip trucks which reduces overall biomass supply chain cost.
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| 10. |
- Anerud, Erik, et al.
(författare)
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Fuel quality of Norway spruce stumps - influence of harvesting technique and storage method
- 2011
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Ingår i: Scandinavian Journal of Forest Research. - : Informa UK Limited. - 0282-7581 .- 1651-1891. ; 26, s. 257-266
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Tidskriftsartikel (refereegranskat)abstract
- The interest in using stump biomass as a biofuel has recently increased in Sweden. The uneven consumption of wood fuel during the year creates a need for storage. This study examined the properties of stump biomass and how they vary at two sites in Sweden depending on harvesting technique, storage method and storage period. Norway spruce stumps, extracted using three different stump harvesting heads (Pallari, Rotary Cutter and Aalto), were stored in windrows or heaps. After 3 months, stumps stored in heaps were gathered into windrows. The fuel quality parameters moisture content (MC), ash content (AC) and calorific value (CV) were evaluated on five occasions in the period May 2008-September 2009. After 16 months of storage, the MC in all treatments had decreased to <25% (wet basis). Average AC decreased from 3.8% to around 1% (dry basis), whereas CV marginally increased. Stumps split during harvesting dried better than those harvested in one piece. The influence of storage method was minimal, although initial storage in heaps allowed better drying in the stumps harvested in one piece. In general, fuel quality improved in all treatments after storage.
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