| 1. |
- Andersson, Anton, et al.
(författare)
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Insights into the Valorization of Electric Arc Furnace Slags as Supplementary Cementitious Materials
- 2023
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Ingår i: Journal of Sustainable Metallurgy. - : Springer. - 2199-3823 .- 2199-3831. ; 10, s. 96-109
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Tidskriftsartikel (refereegranskat)abstract
- The transition to hydrogen-based reduction processes within the iron and steelmaking industry will generate new types of slag compositions that require valorization routes. Using slags as supplementary cementitious materials (SCMs) addresses the carbon dioxide emissions of the cement industry since the SCM requires neither calcination nor clinkering. Conventionally, ironmaking slags from the blast furnace (BF) are recycled as SCMs, i.e., ground granulated BF slag (GGBS). Ideally, future slags from electric arc furnaces (EAFs) operating on hydrogen-based direct reduced iron should be valorized analogously. Since the hydrogen-based process route is not yet realized in an industrial scale, the literature lacks data to support this valorization route, and additionally, literature on scrap-based EAF slags is scarce. Therefore, the present study aimed to offer insights into the utilization of ore-based EAF slags as SCMs based on an industrial slag sample from an EAF operating on hot briquetted iron. The slag was remelted, modified, and water-granulated in laboratory scale, and its performance as an SCM was compared to water-granulated ladle slag and two commercial GGBS. The results showed promising reactivities measured using the R3 isothermal calorimeter-based testing protocol. Based on the comparison to GGBS, the study indicated that generating reactive and appropriate SCMs from EAF slags will partly be a challenge in balancing the crystallization of the MeO-type solid solution rich in magnesia and addressing the iron oxide content in the amorphous phase.
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| 2. |
- Hammarström, Helena, et al.
(författare)
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Fungal Tracheobronchitis in Lung Transplant Recipients : Incidence and Utility of Diagnostic Markers
- 2023
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Ingår i: Journal of Fungi. - : MDPI AG. - 2309-608X. ; 9:1
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Tidskriftsartikel (refereegranskat)abstract
- Fungal tracheobronchitis caused by Aspergillus and Candida spp. is a recognized complication after lung transplantation, but knowledge of the incidence of Candida tracheobronchitis is lacking. The diagnosis relies on fungal cultures in bronchoalveolar lavage fluid (BALF), but cultures have low specificity. We aimed to evaluate the one-year incidence of fungal tracheobronchitis after lung transplantation and to assess the utility of diagnostic markers in serum and BALF to discriminate fungal tracheobronchitis from colonization. Ninety-seven consecutively included adult lung-transplant recipients were prospectively followed. BALF and serum samples were collected at 1, 3 and 12 months after transplantation and analyzed for betaglucan (serum and BALF), neutrophils (BALF) and galactomannan (BALF). Fungal tracheobronchitis was defined according to consensus criteria, modified to include Candida as a mycologic criterion. The cumulative one-year incidence of Candida and Aspergillus tracheobronchitis was 23% and 16%, respectively. Neutrophils of >75% of total leukocytes in BALF had 92% specificity for Candida tracheobronchitis. The area under the ROC curves for betaglucan and galactomannan in BALF to discriminate Aspergillus tracheobronchitis from colonization or no fungal infection were high (0.86 (p < 0.0001) and 0.93 (p < 0.0001), respectively). To conclude, the one-year incidence of fungal tracheobronchitis after lung transplantation was high and dominated by Candida spp. Diagnostic markers in BALF could be useful to discriminate fungal colonization from tracheobronchitis.
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| 3. |
- Isaksson, Jenny, et al.
(författare)
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Improved Settling Mechanisms of an Industrial Copper Smelting Slag by CaO Modification
- 2023
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Ingår i: Journal of Sustainable Metallurgy. - : Springer Nature. - 2199-3823 .- 2199-3831. ; 9:3, s. 1378-1389
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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.
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| 4. |
- Isaksson, Jenny, et al.
(författare)
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Improved Settling Properties of Iron Silicate Slag by CaO Modifications
- 2023
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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.
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| 5. |
- Isaksson, Jenny, et al.
(författare)
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Interactions of Crucible Materials With an FeOx–SiO2–Al2O3 Melt and Their Influence on Viscosity Measurements
- 2023
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Ingår i: Metallurgical and materials transactions. B, process metallurgy and materials processing science. - : Springer Nature. - 1073-5615 .- 1543-1916. ; 54:6, s. 3526-3541
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Tidskriftsartikel (refereegranskat)abstract
- Viscosity is a critical parameter during metal extraction, influencing the settling of valuabledroplets, slag handling, and mass transfer. The viscosity of oxide melts can be measured withhigh-temperature rheometers. During such measurements, interactions between the crucible andthe oxide system can change the chemical composition, melt structure, and thus the viscosity.For increased reliability of viscosity measurements, the influence of crucible and spindlematerials on viscosity must be studied. In this study, the viscosity of a syntheticFeOx–SiO2–Al2O3 melt was measured using the rotating spindle technique and three differentcrucible and spindle materials (Mo, Fe, and Ni) to determine the interactions with the melt andthe influence on viscosity. The interaction was evaluated by comparing the post-experimentalchemical analyses, the Fe/Fe2+/Fe3+ content, visual observations, and using scanning electronmicroscopy–energy dispersive spectroscopy (SEM–EDS). The results showed that all thecrucibles partially dissolved into the melt, affecting the melt structure, composition, and, thus,the viscosities. The viscosity data obtained using the Mo setup interacted the least with the melt,was the most stable, and with the best reproducibility.
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| 6. |
- Isaksson, Jenny
(författare)
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Settling Mechanisms of Valuable Metal Droplets in Iron Silicate Slag
- 2023
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)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 droplets settle under gravity. Reduced copper losses suggest improved raw material efficiency, and the slag becomes a more environmentally safe byproduct as it contains less copper and its associated elements. The copper content in the discarded slag often equals or is higher than in the copper ore, implying that the copper slag is a valuable secondary resource for copper.The settling velocity of droplets and, thus, the metal recovery depends on the slag viscosity, copper droplet size distribution, dissolved copper content, and density difference between the slag phase and the copper droplets. The process parameters, temperature and settling time, theoretically affect the copper recovery, where an extended settling time means that droplets have a longer time to settle, and the temperature affects the viscosity, where a higher temperature means a lower viscosity and thus a higher settling rate. However, the temperature also affects the copper solubility; therefore, the overall effect of temperature on the copper recovery during industrial settling processes is unknown. Modifying the slag composition is another option to alter the viscosity and copper solubility. CaO has experimentally been shown to affect both factors in iron silicate slag positively and is thus a potential modifier for increased copper recovery in a settling process. However, there is a knowledge gap regarding the industrial CaO slag modification in a settling process and the effect on copper droplet size distribution, dissolved copper content, copper recovery, and the relationship between recovery and viscosity. Further research is necessary to bridge the knowledge gap and explore the potential benefits of CaO slag modification for improved copper recovery.Within the scope of this thesis, an industrial trial was conducted with the identified factors, temperature, settling time, and CaO slag modification to gain knowledge of the effect on the industrial settling process. The trial was evaluated by performing a slag characterization focusing on the appearance of copper and its associated elements and phases, copper droplet size distribution, slag matrix copper content, and investigating the slag copper content, copper recovery, and slag viscosity. The results showed that the copper droplets were mainly copper matte and speiss and were primarily associated with the slag phase and occasionally with a chromium-rich spinel and bubbles, which can hinder the settling. The results suggested that the viscosity and slag matrix copper content decreased when the slag was modified with CaO, and the copper droplet size distribution shifted to contain larger droplets. The CaO modification resulted in a higher copper recovery, revealing a linear relationship between the overall recovery and the viscosity.A crucible and spindle material with minimum interaction and influence on viscosity had to be identified to perform the viscosity measurement. Iron silicate slags are the dominating slag used during pyrometallurgical copper extraction of Cu-Fe-S concentrates. The dissolution of the crucible and spindle material into the melt is often analyzed and reported. However, the influence on viscosity is rarely investigated and reported. Three crucibles were studied, Mo, Ni, and Fe, concluding that Mo was preferable for viscosity measurements as it interacted the least with the melt and gave the most stable measurements with the highest reproducibility. Mo was thus the crucible choice for viscosity measurements of the industrial slag with and without CaO modifications. Based on the results from the industrial trial and the experimental evaluation, it was concluded that it is difficult to see an effect of regulating the temperature and settling time in the settling furnace process. It was, however, possible to increase the copper recovery by industrial CaO slag modification, which contributes to an increased raw material efficiency and, thus, a more sustainable pyrometallurgical copper extraction.
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| 7. |
- Isaksson, Jenny, et al.
(författare)
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Industrial Slag Cleaning of Reduced Iron Silicate Slag - Effect of Process Parameters and Slag Modification
- 2022
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Ingår i: Proceedings of Copper 2022 international conference. ; , s. 22-40
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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.
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| 8. |
- Isaksson, Jenny, et al.
(författare)
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Influence of process parameters on copper content in reduced iron silicate slag in a settling furnace
- 2021
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Ingår i: Metals. - : MDPI. - 2075-4701. ; 11:6
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Tidskriftsartikel (refereegranskat)abstract
- During the pyrometallurgical extraction of copper, a significant fraction of this metal is lost with discard slag, which decreases profits and overall copper recovery. These copper losses can be reduced by using a settling furnace, in which suspended droplets containing copper separate from slag under the influence of gravity. An industrial trial was conducted in a settling furnace to increase the knowledge of the effect of temperature and settling time on the copper content of slag, and thus enhance the settling process to increase copper recovery. Slag samples were collected from four sample points: the ingoing and outgoing slag stream, within the furnace during settling, and the granulated slag. The chemical composition of the slag samples was analyzed and compared between batches with different temperatures and settling times. The appearance of copper and its associated phases were analyzed using a scanning electron microscope with an energy‐dispersive X‐ray spectroscopy detector (SEM‐EDS). The results indicated that the outgoing slag copper content increased with an increase in temperature, and it was also concluded to be influenced by the attachment of copper to spinels and gas bubbles. The results indicate that regulating the settling furnace temperature to a lower interval could increase copper recovery.
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| 9. |
- Isaksson, Jenny, et al.
(författare)
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Real-world evaluation of upfront docetaxel in metastatic castration-sensitive prostate cancer
- 2021
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Ingår i: World Journal of Clinical Oncology. - : Baishideng Publishing Group Inc. - 2218-4333. ; 12:11, s. 1009-1022
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUNDThe majority of patients with newly diagnosed metastatic prostate cancer (PC) initially respond to androgen deprivation therapy (ADT) and are classified as metastatic castration-sensitive PC (mCSPC). Following months to years of ADT, the disease tends to become resistant to ADT. Recent randomized phase-III trials demonstrated a survival benefit with the addition of upfront docetaxel to ADT in mCSPC. Following its implementation in routine care, this combined treatment strategy requires more detailed evaluation in a real-world setting.AIMTo assess the real-world outcome and safety of upfront docetaxel treatment in mCSPC.METHODSA multicenter retrospective cohort study in the Southeast Health Care Region of Sweden was performed. This region includes approximately 1.1 million citizens and the oncology departments of Linkoping, Jonkoping, and Kalmar. All patients given upfront docetaxel for mCSPC from July 2015 until December 2017 were included. The primary endpoint was progression-free survival (PFS) at 12 mo, and the secondary endpoints were PFS at 24 mo, overall survival (OS), treatment intensity, adverse events, and unplanned hospitalizations. Exploratory analyses on potential prognostic parameters were performed.RESULTSNinety-four patients were eligible and formed the study cohort. PFS at 12 and 24 mo was 75% (95%CI: 66-84) and 58% (46-70), respectively. OS at 12 and 24 mo was 93% (87-99) and 86% (76-96). A total of 91% of patients (n = 86) were given docetaxel according to the standard protocol of 75 mg/m(2) every 3 wk (6 cycles), while 9% (n = 8) received a modified protocol of 50 mg/m(2) every 2 wk (9 cycles). The average overall dose intensity for those commencing standard treatment was 91%. Univariate Cox regression analyses show that baseline PSA > 180 vs < 180 and the presence of distant metastases vs locoregional lymph node metastases were only negative prognostic factors (HR 2.86, 95%CI: 1.39-5.87, P = 0.0041 and 3.36, 95%CI: 1.03-10.96, P = 0.045). Following multivariate analysis, statistical significance remained for PSA (2.51, 95%CI: 1.21-5.19, P = 0.013) but not for metastatic status (2.60, 95%CI: 0.78-8.65, P = 0.12). Febrile neutropenia was recorded in 21% (n = 20) of patients, and 26% (n = 24) had at least one episode of unplanned hospitalization under and up to 30 d after the treatment course.CONCLUSIONResults from this study support the implementation of upfront docetaxel plus ADT as part of the standard of care treatment strategy in mCSPC.
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| 10. |
- Isaksson, Jenny, et al.
(författare)
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Settling of copper phases in lime modified iron silicate slag
- 2021
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Ingår i: Metals. - : MDPI. - 2075-4701. ; 11:7
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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.
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