| 1. |
- Andersson, Anton, et al.
(författare)
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A Method for Synthesizing Iron Silicate Slags to Evaluate Their Performance as Supplementary Cementitious Materials
- 2023
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Ingår i: Applied Sciences. - : Mdpi. - 2076-3417. ; 13:14
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Tidskriftsartikel (refereegranskat)abstract
- Utilizing iron silicate copper slag as supplementary cementitious material (SCM) is a means to improve resource efficiency and lower the carbon dioxide emissions from cement production. Despite multiple studies on the performance of these slags in SCM applications, the variations in cooling procedure, grinding, and methods for evaluating reactivity limit the ability to assess the influence of chemical composition on reactivity from the literature data. In this study, a methodology was developed to synthesize iron silicate slags, which were then evaluated for their inherent reactivity using the R-3 calorimeter-based experiments. The results demonstrated that laboratory-scale granulation produced the same reactivity as industrially granulated slag. Furthermore, a synthesized triplicate sample showed high repeatability. Based on these two aspects, this method can be used to systematically study the influence of chemical composition on the inherent reactivity of iron silicate slags while producing results that are directly translatable to industrial slags.
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| 2. |
- Andersson, Anton, et al.
(författare)
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Ground granulated iron silicate slag as supplementary cementitious material: Effect of prolonged grinding and granulation temperature
- 2023
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Ingår i: Cleaner Materials. - : Elsevier. - 2772-3976. ; 10
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Tidskriftsartikel (refereegranskat)abstract
- The metallurgical and cement industries contribute significantly to anthropogenic carbon dioxide emissions. Utilizing oxidic by-products from the metallurgical industry as supplementary cementitious materials (SCMs) can improve resource efficiency and reduce emissions from cement production. Iron silicate copper slags have been studied as SCMs, but mainly in systems where Portland cement is used as an activator. There is limited research on the inherent reactivity of the slag under changing processing conditions. The present study offers insight into the effect of granulation temperature and grinding on the inherent reactivity of an industrially produced iron silicate copper slag. The results showed that granulation temperature had an insignificant effect on reactivity, while grinding generated substantial improvements. The latter effect was concluded to stem from the increased specific surface area, increased number of sites for nucleation and growth of hydrates, and changes in the inherent reactivity owing to structural changes induced by the grinding.
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| 3. |
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| 4. |
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| 5. |
- Appelquist, Karin, 1979, et al.
(författare)
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Age, tectonic setting and petrogenesis of the Habo Volcanic Suite: Evidence for an active continental margin setting for the Transscandinavian Igneous Belt
- 2008
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Ingår i: GFF. - 1103-5897. ; 130, s. 123-138
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Tidskriftsartikel (refereegranskat)abstract
- The Habo Volcanic Suite is situated in the south-western part of the Småland-Värmland batholith of the Transscandinavian Igneous Belt (TIB), Sweden. The TIB consists mainly of ~1.85-1.65 Ga granitoids along with associated mafic intrusions and volcanic rocks. The Habo Volcanic Suite comprises mainly intermediate to mafic pyroclastic and resedimented pyroclastic volcanic rocks and is distinct from other, more felsic, Småland-Värmland volcanic units. Two groups can be distinguished geochemically. The first consists of primitive, alkaline mafic samples whereas the second group reflects felsic to intermediate, subalkaline compositions. Mixing or crustal assimilation between a primary basaltic magma and an upper-crustal component is likely to have formed the second group. An active continental margin setting is suggested for the Habo Volcanic Suite, supporting previously suggested theories of an Andean-type convergent continental margin setting for the TIB. U-Pb dating of zircon from the Habo Volcanic Suite yielded two ages; 1795±14 Ma and 1694±7 Ma for low-Th/U rims. The 1795±14 Ma age is interpreted as the crystallization age of the Habo Volcanic Suite, linking it to other Småland volcanic rocks, whereas the 1694±7 Ma rims are interpreted to reflect a metamorphic imprint related to intrusions of TIB 2 granitoids and gabbroic rocks. These interpretations are constrained by LA-ICPMS REE zircon analyses. The Habo Volcanic Suite has been intruded by a TIB-granite, which has also been dated, at an age of 1660±9 Ma.
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| 6. |
- Appelquist, Karin, 1979, et al.
(författare)
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Character and origin of variably deformed granitoids in central southern Sweden: implications from geochemistry and Nd isotopes
- 2011
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Ingår i: Geological Journal. - : Wiley. ; 46:6, s. 597-618
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Tidskriftsartikel (refereegranskat)abstract
- We present major and trace element data for eighteen 1.71–1.66 Ga granitoid samples, and Sm–Nd whole‐rock isotope data for eleven of these samples, in a transect across the border between the Transscandinavian Igneous Belt (TIB) and the Eastern Segment in central southern Sweden. The geochemistry of the granitoids varies from alkalic to alkali‐calcic and peraluminous in the east to predominantly calc‐alkaline and metaluminous in the west. Rocks in the west also have lower SiO2 contents. Trace element signatures favour formation in an active continental margin setting. Nd isotope data are completely overlapping along the transect and initial εNd values are mildly depleted in the range +0.3 to +2.6. The combined data suggest that the magmas were derived mainly from juvenile, pre‐existing crust, increasingly mafic and less alkaline towards the west.
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| 7. |
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| 8. |
- Bok, Gunilla, et al.
(författare)
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Nya möjligheter att minska mängden deponerat gipsavfall från bygg- och ombyggnadsprojekt
- 2018
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Plasterboard is a common building material used in several parts of a building. In the case of retrofitting and demolition a part of the waste consists of components combined with the plasterboards, for example, frame work timber.In the case of new construction and retrofitting, construction waste is produced from clean plasterboard boards, either as cut off pieces or as unused whole boards. This waste can be used as raw material to produce new plasterboards. Manufacturers want to use gypsum from wasted boards to decrease the use of primary gypsum from mining and the quality requirements are relatively easy to achieve.In this project it has been found that the major construction companies already handle gypsum from new construction separately. This waste fraction could already be used in the production of new boards. Gypsum from retrofitting is usually assembled with other building materials and require more extensive efforts to achieve necessary purity to be used in the productions of new boards. Today, plasterboard waste is deposited or used to improve soil and/or sludge. In order to increase the recycling of plasterboards new inventory routines of rebuilding and demolition projects need to be elaborated. New tools and methods for dismantling plasterboard need to be development to achieve safe working environment and environmentally and economically sustainable recycling.Preparation plants producing raw material from plasterboard waste are already in operation. Today the waste mainly is wastage from the production stage. In order to increase the recycling of plasterboards from the construction- and demolition branch new logistic systems need to be developed, for example by creating collection points for gypsum board waste and / or developing new transport vehicles and systems. Prerequisites of changing the system of piece work in the construction industry need to be investigated with the intension to create a more sustainable building industry.
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| 10. |
- Brander, Linus, 1978, et al.
(författare)
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Brittle-plastic deformation in initially dry rocks at fluid-present conditions : transient behaviour of feldspar at mid-crustal levels
- 2012
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Ingår i: Contributions to Mineralogy and Petrology. - : Springer Science and Business Media LLC. - 0010-7999 .- 1432-0967. ; 163:3, s. 403-425
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Tidskriftsartikel (refereegranskat)abstract
- We present detailed microstructural and chemical analyses from an initially dry anorthositic rock deformed during wet amphibolite facies conditions. Three different domains representing the microstructural variation of the deformed samples are investigated in detail in terms of fracture morphology and mode, grain characteristics and chemistry of present phases. Results show transient deformational behaviour where a close interaction between brittle, plastic and fluid-assisted deformation mechanisms can be observed. Our analysis allows us to describe the succession, interrelationships and effects of active mechanisms with progressively increasing strain in three so-called stages. In Stage 1, initial fracturing along cleavage planes promoted fluid influx that caused fragmentation and chemical reactions, producing fine-grained mineral assemblages in the fractures. Deformation twins and dislocations developed in clast pieces due to stress relaxation. Passive rotation of conjugate fracture sets and interconnection of intracrystalline fractures formed micro-shear-zones, constituting Stage 2. Microstructures and grain relationships indicate the activity and fluctuation between fracturing, dissolution-precipitation creep, grain boundary sliding and locally dislocation creep, reflecting the transient behaviour of brittle and plastic deformation mechanisms. Further rotation and widening of fractures into overall foliation parallel shear-bands (Stage 3) promoted strain partitioning into these areas through increased fluid influx, influence of fluid-assisted grain boundary sliding, phase mixing and presence of weak phases such as white mica. We suggest that local differences in fluid availability, volume fraction of weak phases produced by fluid present metamorphic reactions coupled with volume increase and local variations in stress concentration induced transient brittle-plastic behaviour. The studied shear-zone represents an example of the transformation of a rigid dry rock to a soft wet rock during deformation through syntectonic fracturing.
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