| 1. |
- Vrasdonk, Emke, 1990, et al.
(författare)
-
Reference situations for biodiversity in life cycle assessments: conceptual bridging between LCA and conservation biology
- 2019
-
Ingår i: International Journal of Life Cycle Assessment. - : Springer Science and Business Media LLC. - 1614-7502 .- 0948-3349. ; 24:9, s. 1631-1642
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose: In life cycle assessment (LCA) literature addressing land use impacts on biodiversity, several potential reference situations are proposed. However, the lack of guidance on how to apply the proposed reference situations fosters confusion within the topic and raises questions about implications of different reference conceptions. The purpose of this article is to contribute to an improved methodology for assessing biodiversity impacts in LCA through developing the use of reference situations in life cycle impact assessment (LCIA) models of land use. Methods: We analyze how reference situations are currently used when assessing the impacts from land use on biodiversity, as well as how such are defined and used outside LCA, specifically in biodiversity conservation. Based on this review, we provide recommendations to the LCIA research community on how to modify its use of reference situations to enable more relevant assessments of impacts on biodiversity. Results and discussion: It is shown how, in the LCA framework, the use of so-called baseline references dominates, and what shortcomings this implies, including unclear definitions of what “naturalness” and “pristine nature” represent, as well as the lack of reliable data. By contrast, biodiversity conservation, typically aiming at ensuring a favorable conservation status for biodiversity, normally uses limit and target references. These reference situations have the advantage of reflecting, often at an aggregated level, society’s preferences, and values related to biodiversity. Because of this, they also include biodiversity that is dependent on a certain level of management, as in, e.g., semi-natural pastures. This is an important aspect as much of the biodiversity highly valued today belong to this category. Conclusions: We recommend that reference situations for biodiversity in LCIA models should be developed based on biodiversity targets aligned with society’s conservation frameworks. Only measurements of deviation away from or closer to a desired reference situation make it possible for decision makers to distinguish the varying biodiversity-related costs and benefits that are associated with different production systems.
|
|
| 2. |
|
|
| 3. |
- Helldin, Jan Olof, et al.
(författare)
-
Abundance of red-listed species in infrastructure habitats - "responsibility species" as a priority-setting tool for transportation agencies' conservation action
- 2015
-
Ingår i: Nature Conservation. - : Pensoft Publishers. - 1314-6947 .- 1314-3301. ; , s. 143-158
-
Tidskriftsartikel (refereegranskat)abstract
- Road and railroad verges may contribute to nature conservation by providing habitat for many species, but due to limited resources, there is a need to select the most important road and railroad stretches for adapted management. We explore the responsibility species concept as a tool for the Swedish Transport Administration to make this selection. We propose lists of candidate responsibility species based on relative abundance of conservation priority species in the vicinity of roads and railroads, respectively. Abundance data were derived from crowd-sourced species observations. Species with >= 20% of observations in infrastructure habitats were included as candidate responsibility species. For roads 32 species were included in the list, for railroads seven species, with an overlap of three species between the lists. We analyzed habitat and management requirements of the listed species to try identifying functional groups. Most of the species require open or semi-open habitats, mainly dry grassland or heathland on sandy or limy soil, un-sprayed crop fields, or solitary trees. Host plants or substrates include broom (genus Genista), patches of bare soil, and sun exposed wood. Conservation actions prescribed for the species include, e.g., late or irregular mowing, removal of the field layer, planting of host species, protecting and providing particular substrates, and special protection of certain sites. We argue that road and railroad managers are particularly well suited to conduct most of these actions. We consider the responsibility species concept to be a useful tool for transportation agencies to set priorities for adapted verge management, and the current method to be effective in identifying a first list of candidate species. We discuss the possibility of also identifying responsibility habitats or general management measures based on the results.
|
|
| 4. |
- Isaksson, Jenny, et al.
(författare)
-
Improved Settling Mechanisms of an Industrial Copper Smelting Slag by CaO Modification
- 2023
-
Ingår i: Journal of Sustainable Metallurgy. - : Springer Nature. - 2199-3823 .- 2199-3831. ; 9:3, s. 1378-1389
-
Tidskriftsartikel (refereegranskat)abstract
- A significant source of copper losses from pyrometallurgical copper extraction is attributed to dissolved and entrained copper in discarded slag. Entrained copper can be recovered via pyrometallurgical slag cleaning in a settling furnace, where the slag viscosity and copper droplet size distribution (CDSD) are critical parameters. Reduced copper losses suggest improved raw material efficiency, and the slag becomes a more environmentally safe byproduct. In this study, iron silicate slags from a smelting furnace are industrially CaO modified in a fuming furnace to contain a CaO content between 8 and 18 wt.%. The viscosity of slags with and without CaO modifications is evaluated in the temperature range from 1423 to 1723 K. The influences of the CaO modifications on the CDSD, slag matrix copper content, and total copper content were determined. The results show that the slag viscosity decreases with increasing CaO concentrations in the slag. In addition, the copper content decreases in the slag phase, and the CDSD shifts to contain relatively larger droplets. The effect of CaO slag modification reveals a linear relationship between the overall copper recovery and viscosity, which increased from 63 to 88% when the viscosity in the respective batch was 0.51 and 0.25 Pa·s.
|
|
| 5. |
- Isaksson, Jenny, et al.
(författare)
-
Improved Settling Properties of Iron Silicate Slag by CaO Modifications
- 2023
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- One of the most significant sources of copper losses from pyrometallurgical copper extraction is attributed to dissolved and entrained copper in the discarded slag. The entrained copper can be recovered via pyrometallurgical slag cleaning in a settling furnace. Reduced copper losses mean increased smelter profits by improved raw material efficiency, and, in addition, the slag will become a more environmentally safe by-product. One way to increase the copper recovery during the settling process is to modify the slag to improve the properties that decrease copper solubility and slag viscosity. In this study, iron silicate slag was modified using CaCO3 on an industrial scale to evaluate its effect on the settling process. More specifically, the changes in settling were related to the modifications and measurements of slag viscosity and copper droplet size distributions in the slag. The trial was evaluated by comparing the copper content in different batches, the size distribution of copper-containing droplets using automated scanning electron microscopy, and performing rheological studies using a high-temperature rheometer. The results showed that increasing the CaO content of the slag by modification with CaCO3 has a positive effect on the settling process and is thus a possible method to improve the industrial settling process of valuable metals in slag.
|
|
| 6. |
- Isaksson, Jenny, et al.
(författare)
-
Industrial Slag Cleaning of Reduced Iron Silicate Slag - Effect of Process Parameters and Slag Modification
- 2022
-
Ingår i: Proceedings of Copper 2022 international conference. ; , s. 22-40
-
Konferensbidrag (refereegranskat)abstract
- During primary copper sulfide smelting and converting, one of the main copper losses is to the slag, which decreases the overall copper recovery. To decrease the copper losses, which are mechanically entrained or dissolved, a slag cleaning route can be used. At the Boliden Rönnskär smelter in Sweden, the slag from the smelting furnace is treated under reducing conditions in a fuming furnace and then tapped into an electric settling furnace where the copper is separated from the slag under the action of gravity. A trial was conducted in the settling furnace at the Rönnskär smelter to increase the knowledge of the copper content in slag and how the process parameters temperature and settling time influence the final slag copper content. The slag was also modified with CaO, to enhance the slag properties for an increased settling velocity and thus decreased copper content. The trial was evaluated by collecting multiple samples of the ingoing and outgoing slag and then compare the slag copper content in the samples. The results showed that the copper content increased with increasing temperature and decreased when the slag was modified with CaO, both parameters had a more pronounced effect compared to the settling time. The slag was also characterized showing that copper was associated with spinels and bubbles, which hinders the settling.
|
|
| 7. |
- Isaksson, Jenny, et al.
(författare)
-
Settling of copper phases in lime modified iron silicate slag
- 2021
-
Ingår i: Metals. - : MDPI. - 2075-4701. ; 11:7
-
Tidskriftsartikel (refereegranskat)abstract
- Copper in discarded slag decreases the profits and copper recovery during the pyrometallurgical extraction processes. The copper losses to slag can be reduced by using a settling furnace, in which mechanically entrained copper droplets separate from the slag under the action of gravity. The settling rate of entrained droplets can be increased by modifying the slag composition and, thus, the slag properties, which are known to influence the settling rate. The knowledge of industrial CaO slag modification in a reduced iron silicate slag with a Fe/SiO2 ratio close to unity is limited. An industrial trial was thus conducted in an electric settling furnace, where the slag had been pretreated in a fuming furnace, to investigate the effect of CaO slag modification on the final slag copper content. Slag samples were collected from the ingoing and outgoing slag and from within the furnace of batches modified with CaO up to about 16 wt %. The trial was evaluated by comparing the final slag copper content and the copper recovery in the settling furnace. The results indicate that the settling becomes more efficient with the CaO modification as the final slag copper content decreased with increasing CaO content.
|
|
| 8. |
|
|
| 9. |
- Lennartsson, Tommy
(författare)
-
High Nature Value Farming in Sweden
- 2012
-
Ingår i: High nature Value Farming in Europe. - 9783897356573 ; , s. 406-420
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)
|
|
| 10. |
|
|
