Rolf Björheden

Skogforsk · Technology and Forest products

Det pågår en intensiv debatt om samhällets användning av bioenergi. Att bryta beroendet av ändliga, fossila resurser emot ett flöde av av förnybar energi har varit en drivande vision. Osäkerheten om vägen framåt ökar nu till följd av ökad internationell polaridering och konflikt. Därmed har energisäkerhet blivit ett viktigt argument för bioenergi....

The forest industry is constantly striving to increase productivity and cut costs, and many research and innovation projects are currently focusing on semi-automated or autonomous systems. A key element, with several possible solutions, is automated log grasping, where researchers and manufacturers are looking for efficient and sturdy ways to solve...

Highly mechanized forestry operations are essential for efficient timber harvesting. Therefore, the skills of harvester operators appear to be key to productive and sustainable use of the machines. Recent research has revealed a knowledge deficit regarding the work practices of forest machine operators. This urges systematic research into forestry...

Technological development gives forest companies opportunities to maintain competitiveness in the highly cost-sensitive market for forest products. However, no previous studies have examined the technological development decisions made by forest companies or the support tools used when making them. We therefore aimed to describe and analyze 1) the...

This report review the latest developments in Swedish forest fire research, focusing on the intersection with the forestry industry. The report is written in Swedish with an English abstract.

In-terrain transport of wood from sensitive areas with soft soil has always been difficult to perform in without extensive rutting and soil distortion. To carry out logging in wintertime, on frozen ground, is increasingly difficult as prolonged, rainy fall seasons and milder winters have decreased the window of opportunity for such operations. This...

The Nordic forest industry requires just-in-time wood deliveries. Operations must continue regardless of season, weather and terrain. Soil compaction and deep ruts must be avoided while providing high performance and a reasonable working environment for operators. The Xt28 pendulum arm forwarder is a full-size concept forwarder with six hydrostatic...

Purpose of Review Integrated harvesting (i.e., the combined harvesting of roundwood and residues) has a large potential for replication, since all operations produce residues, which could be turned into a collateral product. For this reason, much work has been produced over the years about the subject, and the current bibliography is abundant, frag...

Decision making in forestry is very complex and requires consideration of trade-offs among economic, environmental, and social criteria. Different multi-criteria decision analysis (MCDA) methods have been developed for structuring and exploring the decision-making process of such problems. Although MCDA methods are often used for forest management...

The choice of system for chipping and transport of chips has changed during the last decades in Sweden. Forwarder mounted chippers combined with container trucks or self-loading chip trucks were the dominating chip supply systems in the early 21st century. The new chippertrucks were considered niche machines for small landings close to customer. Cu...

The role of the forest sector in Finland and in Sweden is the starting point for a case study presenting motifs for forest bioenergy in the two countries. Forest bioenergy, evolving in symbiosis with the forest industry, has become important. The successful development builds on piggy-backing conventional forestry, rather than on parallel supply sy...

http://www.skogforsk.se/english/products-and-events/other/forest-energy-for-a-sustainable-future/

In recent years, a lot of attention has been put on improving the eco-friendliness of forest operations, including forest energy harvesting. Examples are identifying types of operations with the lowest impact under varying conditions, purposeful planning procedures as well as follow-up and training programs for machine operators and contractors. Fi...

Forest biomass plays an important role in supplying renewable energy. This chapter discusses the options to increase the output of forest biomass for energy. This could be done in three ways: (1) primary production, which is the net production of tree photosynthesis; secondary production, which includes activities connected with harvesting, interme...

First thinnings are often neglected in Europe due to high harvesting costs. The studied small-tree bundler (Fixteri FX15a) was developed in order to rationalize the integrated harvesting of small-diameter energy wood and pulpwood in thinning operations, and to reduce transportation costs through load compaction. For the time-and-motion study, three...

Fixteri FX15a -kokopuupaalaimen tuottavuustutkimus toteutettiin maaliskuussa 2013 Jyväskylän ympäristössä kolmella puustoltaan erilaisella mäntyvaltaisella kuviolla. Kaksi kuvioista oli energiapuukorjuukohteita. Ensimmäisellä energiapuukuviolla oli tiheä hakkuuta haittaava alikasvos, jossa poistettavien kokopuiden keskikoko oli 27 dm3. Toiselta ene...

FOREWORD At the symposium of IUFRO WP 3.04.02 (Work Study, Payment and Labour Productivity) in Thes-saloniki 1988, a group was appointed to prepare a proposal for an international forest work study nomenclature. This paper contains a proposal for basic time concepts to be used for international comparisons of time study reports. The group pre-parin...

The EU should produce 20% of their energy from renewable sources, including bioenergy, by 2020. Each member state has their own target, for example, Finland should produce 38% and Sweden 49% of their energy from renewable sources by 2020. In this context, the development of forest energy utilization and more effective and economic supply systems pl...

Forests managed by long‐rotation forestry already play an important role as a source for renewable biomass and energy. The biomass output from these forests may be increased through higher harvest levels, but to be sustainable over time, harvest levels cannot exceed forest growth. A large proportion of the tree biomass (tops, foliage, branches, stu...

Studien av klenträdsbuntaren Fixteri FX15a utfördes våren 2013 i mellersta Finland. Maskinen studerades i tre talldominerade provbestånd; ett klent, tätt konfliktbestånd med riklig underväxt och ett likartat konfliktbestånd, men utan underväxt samt i en mera normal förstagallring. Medelstamvolymen i uttaget var 27,44 respektive 84 dm3. Gallringsing...

This study describes developments in large-scale logging technology in Sweden from 1985 to 2010. Data were collected from manufacturers' sales material and from large forest enterprises. On average, forwarders manufactured in 2010 had 27-33% higher boom lifting torque than those manufactured in 1985-1989. The inflation-adjusted prices of medium-siz...

This paper presents a snapshot speculative analysis of some possible effects of the massive windthrow in south Sweden on January 8–9, 2005. Hurricane Gudrun damaged buildings and blocked roads, making large areas inaccessible except by helicopter. Electricity and telecommunications were shambolic. Around 70 million cubic metres were windthrown, equ...

While the production of fuelwood from forest residues in industrial forestry in developed countries is the focus of this chapter, we have included some mention of production under other conditions. In the developing world, fuelwood is often collected from natural forests and shrublands, or grown under agroforestry practices. It provides local peopl...

The use of forest fuels has more than doubled in Sweden over the last 25–30 years. Almost a fifth of the utilized energy is now based on forest biomass. Concurrently, real prices of bioenergy have decreased to less than a third of what they were 25 years ago. Some principal driving forces behind this development are identified and discussed in this...

Bundling is a technology used to create a compressed and uniform handling unit from logging residues and other small size energy wood. The bundles may be handled and transported with the same equipment that is used for conventional roundwood. Bundles also offer other advantages such as “cool systems”, good storing characteristics etc. This study de...

With its increasing use, the production costs of primary forest fuel (PFF) have declined over the last three decades in Sweden. The aims of this study are to quantify cost reductions of PFF production as achieved in Sweden over time, to identify underlying reasons for these reductions, and to determine whether the experience curve concept can be us...

The sawmilling industry is facing serious challenges; intensified competition, increasing substitution of wood for new materials and powerful customers posing extensive new demands. Obstacles for a change towards a more competitive configuration of the sawmilling industry are context and contingency related. Corporate strategy building must be base...

Forests in urban areas are important for recreation. Social, aesthetic and recreational values are at least as important for forest management as economy and conventional forestry considerations. Systems with short, intensive harvesting phases and limited damage to ground and trees are also advantageous, in order to reduce disturbance through harve...

Bioenergy from Sustainable Forestry synthesizes information needed to design or implement sustainable forest management systems for production of biomass for energy in conjunction with other forest products. It is organized around the criteria for sustainable forest management: productivity, environment, social issues, economics, and legal and inst...

Forest operations need comprehensive remodelling in order to integrate forest energy recovery with other harvesting operations. Energy contents and suitability for combustion are important quality measures of forest fuels. The energy fraction from harvesting operations is thus valued in measures other than conventional industry wood - physical volu...

This paper presents results from comparative stud- ies of conventional Scandinavian shortwood process- ing vs a differentiated processing method. The latter signifies processing only sawlogs at the logging site. Pulpwood and forest fuel are transported off the site as undelimbed tree sections. The objective of the studies was to contribute to the d...

The supplier of wood fuels has a large number of interrelated activities to coordinate on the way from raw material source to consumer. Transports, storing and intermediate processing should be decided on for a number of assortments. Storing is a prominent feature of this network flow problem since consumer demand is high when small amounts of raw...

The supplier of forest fuel has a large number of interrelated activities to coordinate on the way from raw material source to consumer. Transports, storing and intermediate processing must be decided on for a number of different raw materials.In this paper, an analysis is performed on the energy supply system of Jämtlandsbränslen, a subsidiary of...

The great variation in technical properties between and within trees indicate that the efficiency of logging would be enhanced if the processing technique is adapted to the varying quality of different trees and stem sections. To evaluate the suggested differentiation in processing technique, time studies must be performed that define exact time co...