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265 Uppsatser om Extraction of harvesting residues - Sida 1 av 18
Jämförande tidsstudie vid riskörning med kompakteringsskotare och traditionell ?lätt? modifierad skotare :
This report is a thesis work for a B.Sc. in Forestry exam at the School for Forest Engineers, SLU.
The work was an assignment from Sydved Energy AB. The aim of the work was to compare the operational productivity between two kinds of forwarders for Extraction of harvesting residues, one forwarder with a special compression device and one ordinary, slightly modified forwarder.
Two sites were studied for each forwarder. The study shows that the annual production was about 11,000 m3 higher for the traditional forwarder. The cost for the traditional forwarder was SEK 0.9 lower per m3.
Development of a method for determination of pesticide residues in honey using liquid chromatography tandem mass spectrometry
Honey is a product that may contain pesticide residues due to contamination from bees pollinating various plants as well as elimination of vermin inside the hive. Different methods are needed for analysis of pesticides, since the term includes a wide range of different substances. National Food Administration lacks a validated method for determination and quantification of pesticides in honey using liquid chromatography tandem mass spectrometry, LC-MS/MS. The technique is especially important in analysis of polar and non-volatile pesticides, where gas chromatography is not functioning optimally. After investigating what pesticides could be found in honey produced in Sweden, a number of four pesticides suitable for analysis with LC-MS/MS was compiled; boscalid, impidacloprid, tau-fluvalinate and thiacloprid.
Anpassad skötsel - exempel på hyggesfritt skogsbruk i Mellannorrland :
Total protection is often the option chosen when protecting forests with high environmental values. An alternative to total protection is application of management regimes that do not interrupt continuity of tree cover. This study focuses mainly on continuous cover forestry (CCF) in forest stands already protected. All objects are situated in the county of Jämtland in northwest Sweden.
The purpose of the study was to attain a greater knowledge about CCF practices.
Analys av mjuka faktorer som påverkar grotuttaget från hygge till avlägg inom Sveaskogs organisation
Biofuels are getting more important as EU plans to replace fossil fuels with renewable energy sources. Because of that Sveaskog has chosen to invest in developing the handling process of logging residue. The company has a joined organisation for handling both round wood and logging residue. They are also working at integrating the forwarding of the logging residue with the rest of the harvesting team. Sveaskog is currently extracting 44 % of the available amount of logging residue.
Ut ur Östersjön genom vassen : beskrivning av övergödningsproblematiken samt optimering av en reningsmetod genom skörd av vattenväxter
This study is based on AgroSeas business idea from environmental problems to valuable resource, with the objective to optimize a method to purify the already eutrophicated Baltic Sea by harvesting water plants, mainly reed. The nutrients will then be recirculated to arable land through residues from biogas production. The amount of nutrients that can be removed by harvesting the biomass
depends on the amounts of biomass and the nutrient content of it, which in turn is strongly dependent on the nutrient concentration of the surrounding water. Vegetation suggested in the study for an effective nutrient uptake is helophytes: reed, cattails, reed canary grass, reed sweet
grass in shallower water and lemnoideaes: duckweed and nymphaeids in the deeper parts.
Competitive species has high purification ability but requires regular maintenance to avoid channeling and overgrowth. Regarding time and method of harvest, effectiveness may be improved by: harvesting plants above the water level and after flowering, a border is kept, harvesting twice a season, a bigger machine and a regular maintenance.
This literature has illuminated a major environmental problem and it has been suggested
optimizations for a method for cleaning the Baltic Sea through harvesting water plants, but to get a
definite answer for the optimal method for each site tests should be carried out, this because many
factors determine to what is suitable for each, specific environment.
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Simulation of rattan harvests in Indonesia : different harvesting pressures and the resulting patterns
The objectives of this research were to determine whether the natural rattan resources in Sulawesi, Indonesia can cope with the strongly increased harvesting pressure that has occurred over the last centuries. I was furthermore looking for patterns in the rattan population dynamics that might give a hint on how the harvesting system could be improved to ensure a maximum sustainable yield. To
answer these questions, I developed an individual-based model to analyse the dynamics of rattan growth in connection with rattan harvests by locals to identify sustainable levels of rattan harvests around villages in Sulawesi, Indonesia. Scenarios with different harvesting intensities were run to compare the change in harvest amount. For a given harvesting pressure, scenarios with a high number of harvesters and a low harvesting frequency had the same effect as scenarios with high harvesting frequencies and a low number of harvesters.
Merkostnader med vinterväghållning för Grot-transporter orsakade av väglagring.
Fuel wood is currently the third largest assortment from the forest in Sweden after pulpwood and lumber. Branches and tops i.e. logging residues are one of the assortments of fuel wood which is a common by-product after harvesting nowadays. The way to utilize, disintegrate and transport the logging residues varies between northern and southern Sweden. Branches and tops are collected throughout the year at appropriate stands, but are consumed mainly wintertime.
Mekaniserad ungskogsbehandling för röjning och skörd :
Earlier attempts at mechanising pre-commercial thinning have been met with varying degrees
of success. Most attempts have been based on techniques where residual stems are straddled.
Early treatment is essential to limit damage on residual trees. One part of the present study is an evaluation of mechanised pre-commercial thinning using the new Vimek 404R. Vimek 404R is a fairly small machine that permits selective removal of stems, making it potentially suitable also for areas overdue for pre-commercial thinning. The study established the level of performance for the machine, as well as the improvement needed to make it an economically viable option.
Från alger till biodiesel - Den italienska drömmen?
This project aims to investigate whether algae can be used for biodiesel production in Italy. Algaes are a good option since they are fast growing and do not occupy arable land. The aspects that have been considered are growing, harvesting, which algae strain that is most suitable, extraction of oil, the production of biodiesel and where in Italy this could be possible due to climate. Cost? and energy calculations have been made to investigate if biodiesel produced from algae would be profitable. During the production of biodiesel there are several residues obtained. When the oil has been extracted from the algae, biogas is produced from the residual biomass by anaerobic digestion and then the electricity that can be produced is supplied to the production of biodiesel.
Påverkande faktorer för grotens fukthalt
The aim of this study was to investigate how seasonal variations affect the quality of logging residues. The study was hosted by VIDA Energy.
Logging residues can be processed and transported within different systems. Today the dominant systems are chipping at landing and bulk transportation of logging residues. In these systems the handling of the logging residues are carried out in the same manner up to the landings.
Moisture content at the time of chipping is the primary quality parameter. Fine fractions of logging residues are strongly dependent on moisture content in storage.
Frysa livsmedelsrester eller kassera dem för biogasproduktion : En studie, ur livscykelperspektiv, av energianvändning och växthusgasutsläpp
Food is widely consumed and in 2011 an average American devoured approximately one ton of food. The production of these goods requires large amounts of energy and contributes to 22-31 % of all greenhouse gas emissions occurring in Europe. More than one third of the produced food is discarded instead of consumed, and food waste make up about 30 % of the waste generated by households. 60 % of this food waste could be avoided if the eatables were handled in a better way.Avoidable food waste arises partly because residues from food are not taken care of, and because the food is not stored in a way that optimise its durability. Residues arises part- ly because of the contradictory and complex demands of everyday life and are, because of our busy lifestyle, difficult to avoid.
Ekonomi vid uttag av långa toppar som skogsbränsle i slutavverkning :
The market for biofuels from the forests have had a positive development and the job initiators for this master´s thesis wanted to examine the profitability of a method for harvesting forest fuel, which was unfamiliar to them. The method was the ?long tree tops-method?, here called the LT-method.
The LT-method is characterised by the fact that timber is harvested as the only roundwood assortment while the rest of the stem, which in other cases would become pulpwood, is harvested as forest fuel together with the logging residues. The method is based on the assumption that advantages in handling of the forest fuel assortment such as increased load weights for forest hauling and truck transportation, should compensate for the lower price for pulpwood when sold as forest fuel.
The aim of the study was to compare the profitability of the LT-method with the GROT-method (harvest of timber, pulpwood and logging residues) and conventional logging without any harvest of forest fuel, and aslo to try to identify factors affecting the profitability of the different methods.
Metodundersökning av tre metoder för kvävemätning i en arktisk äng : Jämförelse mellan mätmetoderna extraktion, inkubation och jonbytesmembran (PRS-sond)
The purpose with this report was to compare three commonly occurring methods for measuring plant available nitrogen in soils. The methods extraction, incubation and Plant root simulator (PRS) probe - an ion exchange membrane (Western Ag Innovations, Inc., Saskatoon, Canada) method were used and comparison between these methods were conducted. A full factorial experiment were set up in northern Finland with the treatments excluding herbivores, warming and fertilization to see how the inorganic nitrogen content in the soil was effected by the treatments. Soil cores were taken and from them a subsample was incubated for 18 days and thereafter analyzed for inorganic N in laboratory. PRS- probes were in the ground for 1 month.
Mindre studie av en ny gallringsmetod i stamtät förstagallring av gran i södra Svergie
The main purpose of this study is to investigate how to reduce the high, and every decade raising, pre-clearance cost. The pre-clearance is today carried out with a brush saw and paid per labour hour. All small trees not suitable for pulpwood are removed to simplify the later work of the harvester.
The study compares the economic results from thinning of four parcels each treated differently regarding harsh or light pre-clearance and extraction of only pulpwood, or both pulpwood and fuel wood.
In this type of spruce stand the study indicates that a lighter pre-clearance, followed up with both pulpwood and a fuel wood extraction, has a much better economy than the traditional method of hard pre-clearance and only pulpwood extraction..
Fukthalt i GROT - påverkande faktorer :
This study was carried out at the request of the bio energy company Naturbränsle. The company handles annually 750 000 m3 of chips from logging residues from a large area, from Östergötland in the south to Härjedalen in the north. In that area, about 50 bio fuel plants are customers. When Naturbränsle deliver chips from logging residues to their customers, the moisture content varies from 30 % to 60 %. The aim of the study was to sort out the affecting factors on the moisture content in the chips during handling and storage processes.