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Växjö, Sweden

Liziniewicz M.,Swedish University of Agricultural Sciences | Eko P.M.,Swedish University of Agricultural Sciences | Klang F.,Sveaskog
Scandinavian Journal of Forest Research | Year: 2016

The aim of this study was to show the effects of five tree-selection strategies when thinning on quality and growth properties of Norway spruce stands, and their potential for improving quality in the stands. The five strategies were thinning to retain high-quality (HQ) and low-quality (LQ) trees, thinning from above (A) and below (B) and thinning to obtain an even distribution of residual trees (S). The study was conducted in two planted stands close to rotation age, located in southern Sweden, which had been thinned twice since the establishment of the thinning experiment. In the two quality-based treatments trees were selected for harvest on the basis of the following growth and quality traits: tree class, vitality, dbh, height, straightness, branch diameter and quality defects. The quality traits were found to be largely independent of tree size, thus the selection strategies based solely on dbh (A and B) did not improve quality within the stands. Thinning targeting HQ traits promoted the retention and growth of HQ trees, and improved overall quality of the stands compared to the other treatments. HQ thinning increased the share of straight trees by 15%, on average. Significant proportions of stem crooks and quality defects detected before the first thinning were invisible 21 years after it. All thinned stands had higher proportions of naturally pruned trees than unthinned stands. The selection method had no influence on periodic annual increment after thinning. © 2016 Taylor & Francis

Futter M.N.,Swedish University of Agricultural Sciences | Keskitalo E.C.H.,Umea University | Ellison D.,Umea University | Pettersson M.,Umea University | And 7 more authors.
Forests | Year: 2011

The Water Framework Directive (WFD) is an ambitious piece of legislation designed to protect and improve water quality throughout Europe. However, forests are only mentioned once in the WFD, and forestry is not mentioned at all, despite its potential implications for streams, rivers and lakes. Here we present a transdisciplinary commentary on the WFD and its implications for forests and forestry in Sweden. This commentary has been prepared by forestry stakeholders, biophysical and social scientists. While we were cognizant of a large body of discipline-specific research, there are very few inter- or trans-disciplinary commentaries which link academic and stakeholder perspectives on the WFD. We had originally felt that there would be little commonality in our concerns. However, we found significant areas of agreement. Our key areas of concern about the implications of the WFD for forestry in Sweden included: (i) concerns about what is meant by good ecological status and how it is assessed; (ii) a perceived lack of clarity in the legal framework; (iii) an inadequate environmental impact assessment process; and (iv) uncertainties about appropriate programs of measures for improving water quality. We were also concerned that ecosystem services provided by forests and the positive effects of forestry on water quality are inadequately recognized in the WFD. © 2011 by the authors.

Wang C.,Swerea MEFOS | Larsson M.,Swerea MEFOS | Larsson M.,Lulea University of Technology | Lovgren J.,SSAB | And 5 more authors.
Energy Procedia | Year: 2014

This study is to investigate different types of biomass products' injection into the blast furnace (BF) to replace pulverized coal injection (PCI). The biomass products covered in the study are charcoal, torrefied material and wood pellets on the basis of Swedish forests. The modelling work has been performed in a specialized BF model. The modelling results show that charcoal has the significant effects on the BF operation. PCI can be replaced fully by charcoal, and only limited amount of torrefied material and wood pellets can be injected into BF. For the studied BF, the annual CO2 emission reduction potential from the replaced amount of PCI when injecting charcoal, torrefied material and wood pellets are about 1140 kton, 260 kton and 230 kton, respectively. In addition, a possible energy saving can be achieved for charcoal injection. A slightly higher P content in the hot metal may occur when injecting torrefied material. © 2014 Published by Elsevier Ltd.

Mellin P.,KTH Royal Institute of Technology | Wei W.,KTH Royal Institute of Technology | Yang W.,KTH Royal Institute of Technology | Salman H.,Sveaskog | And 2 more authors.
Energy Procedia | Year: 2014

Based on the type of BF operated in Sweden, the pulverized coal (PC) has primarily been considered replaceable. If replacing the PC, a reduction of 1.25 Mton CO2 annually is possible, which would require approximately 4 TWh charcoal (0.46 Mton) or 7.14 TWh of dry raw biomass. This amount of biomass is substantial and availability is the main concern discussed in this paper. Uncertainty of the future biomass supply makes predictions beyond 2030 difficult. However, the predictions used in this work indicate that there is an unused potential, which could cover the need of all PCI in Sweden. Other aspects could potentially limit the proportion of PCI replaced by biomass, which should be further investigated. © 2014 Published by Elsevier Ltd.

Sundqvist M.,Swerea MEFOS | Mellin P.,KTH Royal Institute of Technology | Yangb W.,KTH Royal Institute of Technology | Salman H.,Sveaskog | And 3 more authors.
ECOS 2015 - 28th International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems | Year: 2015

The reducing of CO2 allowance promotes steel industry to mitigate CO2 emissions. Utilization of biomass e.g., as injectants in the blast furnace to replace pulverized coal (PC), has been proposed as one promising option to meet these requirements in the short- Term. The aim of this work is to integrate a biomass fast pyrolysis to the iron and steel industry and to investigate the potential effects on the energy consumption and CO2 emission. In this work, an iron and steel plant from Sweden was chosen as a case study. An optimization model was extended to cover the fast pyrolysis units in the system boundary. The fast pyrolysis plant produces different types of biomass products i.e., bio-char, bio-oil and bio-syngas. Different alternative to utilize biomass products within the system were included in the model. The investigation shows that the integration of a fast pyrolysis units has great potential on, not only reducing CO2 emission, the potential energy savings.

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