| 1. |
- Ahmed, Hesham, et al.
(författare)
-
Effect of the Ash from H2‐Rich Carbonaceous Materials on the Physicochemical Properties of Raceway Slag and Coke Reactivity
- 2020
-
Ingår i: Steel Research International. - : John Wiley & Sons. - 1611-3683 .- 1869-344X. ; 91:11
-
Tidskriftsartikel (refereegranskat)abstract
- The iron and steel industry is one of the most important sectors worldwide, and it has a great impact on the global economy; however, this sector is still highly dependent on fossil carbon. To decrease this dependency, approaches to partially replace the injected pulverized coal with secondary, highly reactive, renewable (biomass) and H2‐rich materials have been studied. The injection of such materials is expected to significantly decrease the emitted CO2 from blast furnaces. However, due to the different ash composition of these alternative materials (especially alkali and alkaline earth metals) compared to that of ordinary injected coal, these materials are expected to alter the raceway slag properties and affect the coke reactivity. In the present article, the effect of the ash from different hydrogen‐rich carbonaceous materials on the raceway slag physicochemical properties as well as coke reactivity is reported. The melting characteristics of the ash briquettes in contact with the coke and wettability of the melted ash on the coke surface are determined visually using an optical heating microscope. The effect of the ash on the coke reactivity is studied by means of thermogravimetry under a continuous flow of CO2.
|
|
| 2. |
- Andersson, Anton, et al.
(författare)
-
A Method for Synthesizing Iron Silicate Slags to Evaluate Their Performance as Supplementary Cementitious Materials
- 2023
-
Ingår i: Applied Sciences. - : Mdpi. - 2076-3417. ; 13:14
-
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.
|
|
| 3. |
- Andersson, Anton, et al.
(författare)
-
Ground granulated iron silicate slag as supplementary cementitious material: Effect of prolonged grinding and granulation temperature
- 2023
-
Ingår i: Cleaner Materials. - : Elsevier. - 2772-3976. ; 10
-
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.
|
|
| 4. |
- Andersson, Anton, et al.
(författare)
-
Insights into the Valorization of Electric Arc Furnace Slags as Supplementary Cementitious Materials
- 2023
-
Ingår i: Journal of Sustainable Metallurgy. - : Springer. - 2199-3823 .- 2199-3831. ; 10, s. 96-109
-
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.
|
|
| 5. |
|
|
| 6. |
- Awe, Samuel Ayowole, et al.
(författare)
-
Wise process routes for varying feedstock in base metal extraction
- 2011
-
Ingår i: Proceedings, European Metallurgical Conference EMC 2011. - Germany : GDMB. - 9783940276391 ; , s. 1315-1322
-
Konferensbidrag (refereegranskat)abstract
- In Sweden, there are several large but low-grade ore deposits that have not been extracted so far. The main reason is presence of impurities such as arsenic and antimony that increase the overall cost of the process and make the extraction uneconomical. In-depth experimental studies, plant data and theoretical modelling and innovations are needed to develop new techniques for an efficient use of the resources. Besides, recycling of metals from end of life scrap and metal containing waste, e.g. waste electric and electronic equipment (WEEE), is an important part of a metal production plant. Most of these secondary raw materials contain mixtures of different metals together with various plastics and ceramics that may adversely affect products and by-products of the metallurgical opera-tion. Therefore, a thorough study on how to control possible changes of properties is required. The aim of the research is to develop an optimum combination of hydro- and pyro- metallurgical path-ways to bleed out impurities from the metal extraction chain and/or convert them into valuable by-products. The first part of the current paper focuses on impurity removal from a complex copper concentrate as an upgrading stage. It is shown that by selective dissolution of tetrahedrite in alkaline sulphide solution, antimony and arsenic would be eliminated and the concentrate can be treated in pyro-metallurgical processes. In the second part of the paper, influences of one of the most common and significant compounds that is included in most of the secondary raw materials, alumina Al2O3, on properties of a copper production slag are explained. Results show that increased alumina content of the slag will cause formation of a new phase and rises the liquidus temperature, while its leaching properties are not adversely affected.
|
|
| 7. |
- Babanejad, Safoura, et al.
(författare)
-
High-Temperature Behavior of Spent Li-Ion Battery Black Mass in Inert Atmosphere
- 2022
-
Ingår i: Journal of Sustainable Metallurgy. - : Springer Nature. - 2199-3823 .- 2199-3831. ; 8, s. 566-581
-
Tidskriftsartikel (refereegranskat)abstract
- The increased demand for Li-ion batteries has prompted the scientific community to improve recycling routes in order to reuse the valuable materials in batteries. After their end-of-life, the batteries are collected, discharged, and mechanically disintegrated, generating plastic and metallic streams that are recycled directly; this leaves behind a small particle size fraction known as black mass (BM). BM is composed mainly of graphite and Li-metal complex oxides. Pyrometallurgy is a route known for recycling of BM, in which identifying the BM’s behavior at high temperatures is essential. In this study, two types of BM are characterized in two fractions of 150–700 µm and smaller than 150 µm. The thermal behavior of the BM is studied with thermal analysis techniques. The analyses demonstrate that the mineralogical and morphological properties of the two fractions do not significantly differ, while the amounts of C and organic materials might vary. When the BM was thermally treated, the binders decomposed until a temperature of 500 ℃ was reached, where the volatilization of hydrocarbons was observed, although F mostly persisted in the BM. The Li-metal oxide was partially reduced to lower oxides and Li carbonate at ⁓ 600 ℃, and the main mass loss was caused by carbothermic reduction immediately thereafter. As the products of this process, metallic Co and Ni phases were formed, and part of the graphite remained unreacted. Regarding the Li behavior, it was observed that in the presence of Al, AlLiO2 is the most likely composition to form, and it changes to LiF by increasing the F concentration in the composition.
|
|
| 8. |
|
|
| 9. |
- Canny, G, et al.
(författare)
-
Functional and biochemical characterization of epithelial bactericidal/permeability-increasing protein
- 2006
-
Ingår i: American Journal of Physiology: Gastrointestinal and Liver Physiology. - : American Physiological Society. - 1522-1547 .- 0193-1857. ; 290:3, s. 557-567
-
Tidskriftsartikel (refereegranskat)abstract
- Epithelial cells of many mucosal organs have adapted to coexist with microbes and microbial products. In general, most studies suggest that epithelial cells benefit from interactions with commensal microorganisms present at the lumenal surface. However, potentially injurious molecules found in this microenvironment also have the capacity to elicit local inflammatory responses and even systemic disease. We have recently demonstrated that epithelia cells express the anti-infective molecule bactericidal/permeability-increasing protein (BPI). Here, we extend these findings to examine molecular mechanisms of intestinal epithelial cell (IEC) BPI expression and function. Initial experiments revealed a variance of BPI mRNA and protein expression among various IEC lines. Studies of BPI promoter expression in IECs identified regulatory regions of the BPI promoter and revealed a prominent role for CCAAT/enhancer binding protein and especially Sp1/Sp3 in the basal regulation of BPI. To assess the functional significance of this protein, we generated an IEC line stably transfected with full-length BPI. We demonstrated that, whereas epithelia express markedly less BPI protein than neutrophils, epithelial BPI contributes significantly to bacterial killing and attenuating bacterial-elicted proinflammatory signals. Additional studies in murine tissue ex vivo revealed that BPI is diffusely expressed along the crypt-villous axis and that epithelial BPI levels decrease along the length of the intestine. Taken together, these data confirm the transcriptional regulation of BPI in intestinal epithelia and provide insight into the relevance of BPI as an anti-infective molecule at intestinal surfaces.
|
|
| 10. |
- Cozzi, Elisabetta, et al.
(författare)
-
Identification of long non-coding RNAs involved in leukemogenesis and venetoclax response in acute myeloid leukemia through functional CRISPR-dCas9 interference screens
-
Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Acute myeloid leukemia (AML) is a malignant hematologic disease with poor prognosis. Increased understanding of disease biology is therefore needed to improve outcome for patients. While the protein-coding genome is well characterized in AML, knowledge about the involvement of non-coding genes is very limited in AML. Here, it was sought to investigate how long non-coding RNAs (lncRNAs) could contribute to disease biology and treatment resistance in AML. Three high-throughput lncRNA-CRISPR-interference screens were performed in MOLM-13 cells, knocking down about 8000 lncRNA expressed in hematopoietic cells. Effects on cell proliferation, cell differentiation and response to the anti-leukemic Bcl-2-inhibitor venetoclax were investigated upon lncRNA repression. LncRNAs most likely to positively or negatively regulate these processes were identified and top lncRNA candidates investigated with respect to expression in AML and healthy CD34+ cells and clinical AML correlations. Four lncRNAs involved in AML cell proliferation were identified (lncRNAs MIR17HG, CATG00000056335, CATG00000095269, CATG00000002239), two lncRNAs involved in differentiation (lncRNAs RP11-444A22.1, CATG00000058672) and seven lncRNAs implicated in venetoclax response. Among those, enhanced expression of proliferation-promoting lncRNA MIR17HG significantly correlated with poor outcome in AML patients (p= 0.03; p= 0.016). Further, lncRNA RP11-444A2 was identified as a predicted negative regulator of cell differentiation and was found to correlate with poor outcome (p=0.014). Further, lncRNA AC009299.3, predicted in venetoclax sensitivity, was found to be associated with poor outcome (p<0.0001), adverse risk (p=0.0014) and increased age (p=0.0045) in AML patients. Together, this study identified 14 lncRNAs proposed to be implicated in key leukemogenic events, highlighting their potential for elucidating AML biology, prognosis or treatment-response prediction and/or therapeutic use.
|
|
| 11. |
- Deneberg, Stefan, et al.
(författare)
-
microRNA-34b/c on chromosome 11q23 is aberrantly methylated in chronic lymphocytic leukemia
- 2014
-
Ingår i: Epigenetics. - : Informa UK Limited. - 1559-2294 .- 1559-2308. ; 9:6, s. 910-917
-
Tidskriftsartikel (refereegranskat)abstract
- A commonly deleted region in chronic lymphocytic leukemia (CLL) is the 11q22-23 region, which encompasses the ATM gene. Evidence suggests that tumor suppressor genes other than ATM are likely to be involved in CLL with del(11q). A microRNA (miR) cluster including the miR-34b and miR-34c genes is located, among other genes, within the commonly deleted region (CDR) at 11q. Interestingly, these miRs are part of the TP53 network and have been shown to be epigenetically regulated. In this study, we investigated the expression and methylation status of these miRs in a well-characterized cohort of CLL, including cases with/without 11q-deletion. We show that the miR-34b/c promoter was aberrantly hypermethylated in a large proportion of CLL cases (48%, 25/52 cases). miR-34b/c expression correlated inversely to DNA methylation (P = 0.003), and presence of high H3K37me3 further suppressed expression regardless of methylation status. Furthermore, increased miR-34b/c methylation inversely correlated with the presence of 11q-deletion, indicating that methylation and del(11q) independently silence these miRs. Finally, 5-azacytidine and trichostatin A exposure synergistically increased the expression of miR-34b/c in CLL cells, and transfection of miR-34b or miR-34c into HG3 CLL cells significantly increased apoptosis. Altogether, our novel data suggest that miR-34b/c is a candidate tumor suppressor that is epigenetically silenced in CLL.
|
|
| 12. |
- Deneberg, Stefan, et al.
(författare)
-
Prognostic DNA methylation patterns in cytogenetically normal acute myeloid leukemia are predefined by stem cell chromatin marks
- 2011
-
Ingår i: Blood. - : American Society of Hematology. - 0006-4971 .- 1528-0020. ; 118:20, s. 5573-5582
-
Tidskriftsartikel (refereegranskat)abstract
- Cytogenetically normal acute myeloid leukemia (CN-AML) comprise between forty and fifty percent of all adult acute myeloid leukemia (AML) cases. In this clinically diverse group molecular aberrations such as FLT3ITD, NPM1 and CEBPA mutations recently have added to the prognostic accuracy. Aberrant DNA methylation is a hallmark of cancer including AML. We investigated in total 118 CN-AML samples in a test and a validation cohort for genome-wide promoter DNA methylation with Illumina Methylation Bead arrays and compared them to normal myeloid precursors and global gene expression. IDH and NPM1 mutations were associated with different methylation patterns (p=0.0004 and 0.04, respectively). Genome-wide methylation levels were elevated in IDH mutated samples (p=0.006). We observed a negative impact of DNA methylation on transcription. Genes targeted by Polycomb group (PcG) proteins and genes associated with bivalent histone marks in stem cells showed increased aberrant methylation in AML (p<0.0001). Furthermore, high methylation levels of PcG target genes were independently associated with better progression free (OR 0.47, p=0.01) and overall survival (OR 0.36, p=0.001). In summary, genome wide methylation patterns show preferential methylation of PcG targets with prognostic impact in CN-AML.
|
|
| 13. |
- Eriksson, Anna, et al.
(författare)
-
Epigenetic aberrations in acute myeloid leukemia : Early key events during leukemogenesis
- 2015
-
Ingår i: Experimental Hematology. - : Elsevier BV. - 0301-472X .- 1873-2399. ; 43:8, s. 609-624
-
Tidskriftsartikel (refereegranskat)abstract
- As a result of the introduction of new sequencing technologies, the molecular landscape of acute myeloid leukemia (AML) is rapidly evolving. From karyotyping, which detects only large genomic aberrations of metaphase chromosomes, we have moved into an era when sequencing of each base pair allows us to define the AML genome at highest resolution. This has revealed a new complex landscape of genetic aberrations where addition of mutations in epigenetic regulators has been one of the most important contributions to the understanding of the pathogenesis of AML. These findings, together with new insights into epigenetic mechanisms, have placed dysregulated epigenetic mechanisms at the forefront of AML development. Not only have several new mutations in genes directly involved in epigenetic regulatory mechanisms been discovered, but also previously well-known gene fusions have been found to exert aberrant effects through epigenetic mechanisms. In addition, mutations in epigenetic regulators such as DNMT3A, TET2, and ASXL1 have recently been found to be the earliest known events during AML evolution and to be present as preleukemic lesions before the onset of AML. In this article, we review epigenetic changes in AML also in relation to what is known about their mechanism of action and their prognostic role.
|
|
| 14. |
|
|
| 15. |
- Heikkinen, Eetu-Pekka, et al.
(författare)
-
A dialogue about teaching and learning metallurgy in Finland and Sweden
- 2019
-
Ingår i: Pedaforum 5.–6.6. 2019 Helsinki. - : University of Helsinki. ; , s. 187-187
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Metallurgy is taught as a part of degree programmes of process and environmental engineering at the University of Oulu in Finland and at the Luleå University of Technology in Sweden. In both universities metallurgy education is organised by units very closely linked with metallurgical industry which is the most significant employer of the students graduating in metallurgy. The purpose of this presentation is to consider the state of pedagogy in the education of metallurgy in these two universities with a dialogue of teachers representing both universities. The aim is not only to find the similarities and differences, but also to find ways to improve teaching and learning based on the ideas raised in the dialogue. Key issues in the education of metallurgy, as in all engineering education, are the connections between theory and practice and how these connections are seen and adopted by students while their expertise in metallurgy develops. Our dialogue is based on how these connections are recognised and taken into account in teaching and learning of metallurgy as well as in the development of metallurgical expertise of both students and teachers. We will also discuss what kind of pedagogical solutions that can be used to support this development.
|
|
| 16. |
|
|
| 17. |
- 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.
|
|
| 18. |
- 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.
|
|
| 19. |
- 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.
|
|
| 20. |
- Isaksson, Jenny, et al.
(författare)
-
Influence of process parameters on copper content in reduced iron silicate slag in a settling furnace
- 2021
-
Ingår i: Metals. - : MDPI. - 2075-4701. ; 11:6
-
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.
|
|
| 21. |
- Isaksson, Jenny, et al.
(författare)
-
Interactions of Crucible Materials With an FeOx–SiO2–Al2O3 Melt and Their Influence on Viscosity Measurements
- 2023
-
Ingår i: Metallurgical and materials transactions. B, process metallurgy and materials processing science. - : Springer Nature. - 1073-5615 .- 1543-1916. ; 54:6, s. 3526-3541
-
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.
|
|
| 22. |
- Isaksson, Jenny
(författare)
-
Settling Mechanisms of Valuable Metal Droplets in Iron Silicate Slag
- 2023
-
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.
|
|
| 23. |
- 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.
|
|
| 24. |
- Isaksson, Jenny
(författare)
-
Slag Cleaning of a Reduced Iron Silicate Slag by Settling : Influence of Process Parameters and Slag Modification on Copper Content
- 2021
-
Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- During the pyrometallurgical extraction of copper, a significant part of the copper is lost with discard slag, which decreases profits, overall copper recovery, and efficiency of raw material usage. Smelting furnace slag usually has a copper content that is close to or higher than that of copper ores. The investigation of copper losses to slag is thus a task of practical significance, as the ore grades are depleting. Slag cleaning, e.g., a settling furnace, can reduce copper losses to slag as the mechanically suspended copper-containing droplets separate from slag under the action of gravity and can hence be recovered. An industrial trial was conducted in an electric settling furnace with slag originating from an electric smelting furnace and processed in a zinc fuming furnace. The trial was conducted to increase the understanding of copper losses to slag and how the process parameters temperature and settling time influence the slag copper content. The obtained slag samples were also evaluated to gain better insights as to the settling mechanism and, if any, factors that hinder the copper phases from settling. Slag modification with CaO was also evaluated to investigate how the modification influences the settling of copper phases and, thus, the final slag copper content. Samples collected during the industrial trial were the basis for the evaluation in the current work. The samples came from batches with varying temperatures, settling times, and CaO content collected at four different sample positions. Instrumental techniques, including XRF, FAAS, ICP-SFMS, and SEM-EDS, were used to analyze the chemical compositions of the samples and the appearance of copper and associated phases. The results indicated that the copper content of outgoing slag increased with increasing temperature in the evaluated interval. The copper content was also concluded to be more strongly affected by the temperature compared to the settling time. Regulating the temperature to the lower temperature interval in the settling furnace could thus decrease the final slag copper content. During the slag characterization, it was found that suspended copper-containing phases were hindered from settling, due to the attachment to solid phases and gas bubbles in the slag. By controlling and minimizing the presence of the bottom buildup and thus solid phases in the slag, the copper content can be decreased. The results indicated that the CaO slag modification decreased the final slag copper content, and can thus be used as a modifier for increased settling.
|
|
| 25. |
- Kalushkova, Antonia, et al.
(författare)
-
One Omics Approach Does Not Rule Them All : The Metabolome and the Epigenome Join Forces in Haematological Malignancies
- 2021
-
Ingår i: EPIGENOMES. - : MDPI. - 2075-4655. ; 5:4
-
Tidskriftsartikel (refereegranskat)abstract
- Aberrant DNA methylation, dysregulation of chromatin-modifying enzymes, and microRNAs (miRNAs) play a crucial role in haematological malignancies. These epimutations, with an impact on chromatin accessibility and transcriptional output, are often associated with genomic instability and the emergence of drug resistance, disease progression, and poor survival. In order to exert their functions, epigenetic enzymes utilize cellular metabolites as co-factors and are highly dependent on their availability. By affecting the expression of metabolic enzymes, epigenetic modifiers may aid the generation of metabolite signatures that could be utilized as targets and biomarkers in cancer. This interdependency remains often neglected and poorly represented in studies, despite well-established methods to study the cellular metabolome. This review critically summarizes the current knowledge in the field to provide an integral picture of the interplay between epigenomic alterations and the cellular metabolome in haematological malignancies. Our recent findings defining a distinct metabolic signature upon response to enhancer of zeste homolog 2 (EZH2) inhibition in multiple myeloma (MM) highlight how a shift of preferred metabolic pathways may potentiate novel treatments. The suggested link between the epigenome and the metabolome in haematopoietic tumours holds promise for the use of metabolic signatures as possible biomarkers of response to treatment.
|
|
| 26. |
- Lennartsson, Andreas, et al.
(författare)
-
A murine antibacterial orthologue to human bactericidal/permeability-increasing protein (BPI) is expressed in testis, epididymis, and bone marrow.
- 2005
-
Ingår i: Journal of Leukocyte Biology. - : Oxford University Press (OUP). - 1938-3673 .- 0741-5400. ; 77:3, s. 369-377
-
Tidskriftsartikel (refereegranskat)abstract
- The bactericidal/permeability-increasing protein (BPI), stored in human neutrophil granulocytes, is cytotoxic against Gram-negative bacteria. Several genes related to BPI cluster on human chromosome 20 and on mouse chromosome 2, but expression and characterization of a BPI ortholog in the mouse have not been reported. We asked whether BPI is structurally and functionally conserved between humans and mice and whether murine BPI might be synthesized in neutrophils as well as in other tissues. We report the isolation of a murine full-length cDNA encoding a 54-kDa protein, showing 53% amino acid identity and 71% similarity, to human BPI. The murine BPI and human BPI genes show a similar exon-intron organization. Murine BPI mRNA was detected in testis, epididymis, and bone marrow, as well as in Sertoli and promyelocytic cell lines. Although levels of BPI mRNA in human and murine testis were comparable, expression in murine bone marrow cells was low as compared with that in human bone marrow. BPI protein showed a cytoplasmic, granular localization in mature neutrophils. BPI gene expression in Sertoli and promyelocytic cells was enhanced several-fold by all-trans retinoic acid. Overexpression of murine BPI in human embryonic kidney 293 cells resulted in antibacterial activity against Escherichia coli, comparable with that obtained with human BPI. In conclusion, it was demonstrated that mouse neutrophils store BPI with antibacterial activity and that murine BPI is also expressed in testis and epididymis.
|
|
| 27. |
- Lennartsson, Andreas, et al.
(författare)
-
All-trans retinoic acid-induced expression of bactericidal/permeability-increasing protein (BPI) in human myeloid cells correlates to binding of C/EBP{beta} and C/EBP{varepsilon} to the BPI promoter.
- 2006
-
Ingår i: Journal of Leukocyte Biology. - : Oxford University Press (OUP). - 1938-3673 .- 0741-5400. ; 80:1, s. 196-203
-
Tidskriftsartikel (refereegranskat)abstract
- Bactericidal/permeability-inereasing protein (BPI) neutralizes the proinflammatory effects of lipopolysaccharide and is of potential clinical use in the treatment of fulminant Gram-negative infections. BPI is a cationic protein with antibacterial activity stored in azurophil (primary) granules of neutrophil granulocytes. However, the absence of BPI in patients with specific granule deficiency indicates a transcriptional control of BPI, which is distinct from that of other azurophil granule proteins. Accordingly, we demonstrate in vivo that the BPI mRNA level peaks, together with mRNA for specific granule proteins, during the myelocytic and metamyelocytic stage of granulocytic maturation. The human promyelocytic cell line NB4 expresses several azurophil granule proteins, but expression of BPI is undetectable. We show that treatment of NB4 cells with all-trans retinoic acid (ATRA) induces BPI expression at mRNA and at protein level. The induction is dependent on de novo protein synthesis, as judged by sensitivity to cycloheximide. Previous investigations have indicated a potential role of CCAAT/enhancer-binding protein (C/EBP) transcription factors in the regulation of BPI expression. Here, we show that induction of NB4 cells with ATRA correlates to direct binding of C/EBP beta and C/EBP epsilon to the proximal BPI promoter, as determined by electrophoretic mobility shift analysis and chromatin immunoprecipitation. The dependency on C/EBP beta and C/EBP epsilon provides an explanation for delayed BPI mRNA expression, as compared with mRNA of other azurophil granule proteins.
|
|
| 28. |
|
|
| 29. |
- Lennartsson, Andreas, 1980-
(författare)
-
Application of FactSage in Education within Process Metallurgy at Luleå University of Technology
- 2017
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Luleå University of Technology are educating engineers, teachers nurses etc. The research subject Process Metallurgy is involved in the education of engineers within the MSc program Sustainable Process Engineering and especially the focus area called Sustainable Minerals and Metals Processing.FactSage is used in the education to introduce the possibilities, advantages and disadvantages with computational thermochemistry. To do this, the different FactSage modules are introduced in different courses both during lab-sessions and as a supplement to practical projects.This presentation will give some examples on how FactSage and computational thermochemistry is taught within the program.
|
|
| 30. |
- Lennartsson, Andreas, et al.
(författare)
-
Characterisation of buildup in an electric furnace for smelting copper concentrate
- 2015
-
Ingår i: Canadian metallurgical quarterly. - 0008-4433 .- 1879-1395. ; 54:4, s. 477-484
-
Tidskriftsartikel (refereegranskat)abstract
- The results from a characterization of buildup in an electric smelting furnace for treating copper-rich feed material at the Boliden Rönnskär smelter in Sweden are presented. The aim of the work was to obtain better knowledge about the mechanisms behind the formation of the buildup. Samples from the buildup were taken during the rebuilding of the furnace. The samples were characterized using chemical and mineralogical techniques. The buildup consists mainly of different phases such as spinel, matte, olivine and metalloids and has a complex and varying mineralogy, which indicates that the buildup is not formed under equilibrium conditions.
|
|
| 31. |
- Lennartsson, Andreas, et al.
(författare)
-
Development of a model for copper converting
- 2013
-
Ingår i: Canadian metallurgical quarterly. - 0008-4433 .- 1879-1395. ; 52:4, s. 422-429
-
Tidskriftsartikel (refereegranskat)abstract
- Building on previous work reported in the literature, a dynamic model of the operation of the Peirce-Smith Converter has been developed to describe the distribution of the major elements present. The fundamental principle of the model was a thermodynamic calculation. The situation of non-equilibrium conditions was considered by dividing the converter into different zones linked by predefined flow parameters. The model was verified against actual converter plant data, with the simulated results for the major elements being in good agreement with the plant data. The agreement between plant and calculated data for Pb, and Zn was not as good and more work is required regarding this aspect.
|
|
| 32. |
- Lennartsson, Andreas
(författare)
-
Development of a process model for a Peirce-Smith converter
- 2013
-
Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Copper was one of the first metals ever extracted and used by mankind. It is used for its unique properties, like corrosion resistance, good workability, high thermal conductivity and attractive appearance. New mines are opened to maintain a supply of primary feedstock to copper smelters. These new deposits are in many instances found to have a more complex mineralogy with several minor elements. Besides treating primary material, copper smelters also show an increasing interest in treating secondary material, such as copper containing scrap from waste electric and electronic equipment, which also have a complex composition.Waste electric and electronic equipment are first disassembled and upgraded by mechanical processing, generating a product stream called e-scrap, that can be added directly to the smelting processes as cold material or melted in a separate furnace producing a metallic alloy (referred to as black copper) and a slag phase. The black copper can be refined in different ways, whereof one is by using it as a secondary feed material for input to Peirce-Smith converters. Consequently the load of minor elements to the converter can be expected to increase with an increased treatment of e-scrap.This increased complexity of the raw material can potentially lead to smelter plants having to deal with a feedstock containing several minor elements such as; antimony, bismuth, arsenic, gold, silver, etc. in levels that can influence the ability to, in a cost effective way, maintain the final grade of the copper cathode. Process simulations can be an important tool for understanding the impact of process parameters on the product quality and for the purpose of process optimisation. In the present work a dynamic, non-equilibrium model based on thermodynamics over the Peirce-Smith converter has been developed. The non-equilibrium conditions have been simulated by introducing individual but linked segments. The purpose of using segments was to consider different reaction zones which yield different conditions within the converter. The model was validated using plant data and showed good agreement for the major elements. The agreement between plant and calculated data for Pb, and Zn was not as good and more work is required regarding this aspect. The model was used to investigate the influence on the distribution of Bi and Sb during addition of black copper with or without slag. When black copper is added to a blow, the removal of Bi and Sb becomes lower compared to a blow without addition of black copper. Similar result is obtained during addition of black copper with slag. To maintain a total removal of Bi and Sb in similar levels as a blow without black copper, the black copper should be added as early as possible during the converting operation.
|
|
| 33. |
- Lennartsson, Andreas, 1980-, et al.
(författare)
-
Large-Scale WEEE Recycling Integrated in an Ore-Based Cu-Extraction System
- 2018
-
Ingår i: Journal of Sustainable Metallurgy. - : Springer. - 2199-3823 .- 2199-3831. ; 4:2, s. 222-232
-
Tidskriftsartikel (refereegranskat)abstract
- At Boliden’s Rönnskär smelter, WEEE is smelted in a Kaldo process and the black copper, together or without the slag, is charged to the PS converter. This process route has proven to be a viable way to obtain a high WEEE smelting capacity in an originally ore-based process system. Experience shows that the slag in the PS converter is usually not fully liquid, and the amount of solids present in the slag increases due to introduction of slag and black copper from WEEE smelting. The effect of increased content of Al2O3 and Cr in the slag on the liquidus temperature has been calculated using FactSage both for the converter slag and for the slag in the electric smelting furnace. The potential of changed slag chemistry is discussed. The consequences of the applied praxis on the removal of Antimony in the converter have been modeled using SimuSage.
|
|
| 34. |
|
|
| 35. |
|
|
| 36. |
- Lennartsson, Andreas, et al.
(författare)
-
Modelling of a Cu-making converter, a necessary tool for improved recycling
- 2014
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Process simulation is an important tool for understanding the impact of process parameters on the product quality and for the purpose of process optimisation. In the present work a dynamic, non-equilibrium model based on thermodynamics over the Peirce-Smith converter has been developed. The non-equilibrium conditions have been simulated by introducing individual but linked segments. The purpose of using segments was to consider different reaction zones which yield different conditions within the converter. The model was validated using plant data and showed good agreement for the major elements
|
|
| 37. |
|
|
| 38. |
- Lennartsson, Andreas, et al.
(författare)
-
Thermodynamic process modelling of black copper addition to a Peirce-Smith converter: effect on the distribution of antimony and bismuth
- 2014
-
Ingår i: Mineral Processing and Extractive Metallurgy. - 0371-9553 .- 1743-2855. ; 123:3, s. 157-164
-
Tidskriftsartikel (refereegranskat)abstract
- The effect of adding black copper, originating from treating waste electrical and electronic equipment (WEEE), to a Peirce-Smith converter has been investigated by using a thermodynamic process model. The model was formulated, by the authors, in an earlier publication and expanded, in the present work, to include the minor elements antimony and bismuth. The results show that the model describes the distribution of Bi well, whereas the distribution of Sb is not described as well and should only be used for trends. Addition of black copper lowers the removal of Bi and Sb compared to a converter cycle without addition. To maintain a good removal of Bi and Sb, black copper should be added as early as possible during a converter cycle.
|
|
| 39. |
- Lennartsson, Andreas
(författare)
-
Transcriptional control of Bactericidal/permeability increasing protein (BPI) and cathepsin G in myeloid cells
- 2004
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The neutrophil store its effector proteins in several distinct types of cytoplasmic granules, developed sequentially during cell maturation. The different subtypes of granules have unique protein content and functional characteristics. The formation of each granule subtype coincides with the biosynthesis of its content. Granule proteins synthesised during the formation of a granule subtype are thus stored in that granule type. Therefore, the temporal regulation of granule protein expression is an important mechanism by which sorting into different granule subtypes is achieved. BPI (bactericidal/permeability increasing protein) is a cationic protein with antibacterial activity, present in azurophil (primary) granules of neutrophils. BPI neutralises the pro-inflammatory effects of LPS and is of potential clinical use in the treatment of fulminant gram-negative infections. The expression of BPI occurs during the promyelocyte stage of neutrophil maturation, but absence of BPI in patients with specific granule deficiency indicates a transcriptional control distinct from that of other azurophil granule proteins. In the present thesis have I show that AML1, Sp3 and PU.1 activate the BPI promoter in HL60 cells. Moreover, all trans retinoic acid (ATRA)-induced BPI expression in NB4 cells correlates with C/EBP binding to BPI promoter. Furthermore, have I identified a mouse BPI orthologue that is expressed in both bone marrow and testis. Cathepsin G is a haematopoietic serine protease also stored in azurophil granules of neutrophils. I show that transcription of cathepsin G is activated by assembly of an enhanceosome including cis-elements for C/EBP and c-myb, and a GC-rich region, and corresponding trans-factors. Binding of trans-factors C/EBPa and C/EBPe to the enhancesome is shown by chromatin immunoprecipitation. Furthermore, PU.1 binding to the cathepsin G promoter in monocytic cells confers a high cathepsin G mRNA expression.
|
|
| 40. |
- Lennartsson, Andreas, et al.
(författare)
-
Understanding the bottom buildup in an electric copper smelting furnace by thermodynamic calculations
- 2019
-
Ingår i: Canadian metallurgical quarterly. - : Taylor & Francis. - 0008-4433 .- 1879-1395. ; 58:1, s. 89-95
-
Tidskriftsartikel (refereegranskat)abstract
- Thermodynamic calculations were used to investigate the liquidus temperature of the slag and the possible influence on the buildup formation in an electric copper smelting furnace. The impact of parameters such as Fe/SiO2 ratio, partial pressure of oxygen and the content of the oxides ZnO, Al2O3 and Cr2O3 in the slag were investigated with respect to the liquidus temperature of the slag. Results show that the chromium content in the slag has the greatest impact on the liquidus temperature and on the formation of solid particles. The characterization of the buildup done earlier showed that spinel phases were among the dominating phases. This is supported by the thermodynamic calculations in the present paper, where the chromite solid solution was found to be the primary precipitation phase.
|
|
| 41. |
- Lennartsson, Andreas
(författare)
-
Wise Process Routes for Varying Feedstock in Base Metal Extraction : Modelling of a Peirce-Smith Converter and Investigation of Buildup Formation in an Electric Smelting Furnace
- 2015
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Copper, like silver and gold, is one of the metals that are known to have been worked by some of the oldest civilisations on record. It is used forits unique properties such as corrosion resistance, good workability, high thermal conductivity and attractive appearance. New mines are opened to maintain a supply of primary feedstock for copper smelters. These new deposits are in many instances found to have a more complex mineralogy with several minor elements. Besides treating primary material, copper smelters are also showing an increasing interest in treating secondary materials, such as copper containing scrap from waste electrical and electronic equipment, which also have a complex composition. This increased complexity of the raw material can potentially lead to smelter plants having to deal with a feedstock containing several minor elements, including antimony, arsenic, bismuth, gold, silver, etc., at levels that can influence the ability to, in a cost effective way, maintain the final grade of the copper cathode. Process simulations can be an important tool for understanding the impact of process parameters on product quality and for the purpose of process optimisation. In the present work a dynamic, non-equilibrium model based on thermodynamics over the Peirce-Smith converter has been developed. The model was found to predict the composition of the main condensed phases well. Thermodynamic calculations in combination with characterisation have also been used to understand the buildup in an electric smelting furnace. Results from the characterisation and the modelling showed that the buildup consists mainly of different phases such as spinel, matte, olivine and metalloids and has a complex and varying mineralogy, which indicates that the buildup is not formed under equilibrium conditions. During the modelling the impact of parameters such as Fe/SiO2ratio, partial pressure of oxygen and the content of the oxides ZnO, Al 4O3 and Cr2O3 in the slag were investigated with respect to the liquidus temperature of the slag. The modelling showed that the chromium content in the slag has the greatest impact on the liquidus temperature and on the formation of solid particles. The thermodynamic modelling supports the result from the characterisation.The combination of characterisation, thermodynami-based modelling and process knowledge gives further understanding of element distribution. This enhances the potential to adjust for variations in raw material feed and flexible process routes.
|
|
| 42. |
|
|
| 43. |
- Lotfian, Samira, et al.
(författare)
-
Evaluating the potential of plastic-containing materials as alternative reducing agents
- 2019
-
Ingår i: Canadian metallurgical quarterly. - : Taylor & Francis. - 0008-4433 .- 1879-1395. ; 58:4, s. 389-399
-
Tidskriftsartikel (refereegranskat)abstract
- The amount of discarded plastic-containing materials is increasing, and one option to help with this issue is to use these materials in bath smelting processes. The injection of plastic-containing materials to partially substitute coal in zinc-fuming processes has been studied in an industrial trial at Boliden–Rönnskär smelter. To evaluate the potential of plastic-containing materials, thermodynamic calculations were performed in this study. In the first step, a thermodynamic calculation was performed for trials with only coal injection, and then this calculation was applied to trials with the co-injection of plastic materials. The thermodynamic calculation shows that not all the injected coal participates in the reactions within the slag. Similarly, the calculation with the co-injection of plastic-containing materials shows that different amounts of each plastic material participate in the reactions within the slag bath.
|
|
| 44. |
- Lotfian, Samira, et al.
(författare)
-
Plastic-containing materials as alternative reductants for base metal production
- 2019
-
Ingår i: Canadian metallurgical quarterly. - : Taylor & Francis. - 0008-4433 .- 1879-1395. ; 58:2, s. 164-176
-
Tidskriftsartikel (refereegranskat)abstract
- Shredder residue materials are produced after the removal of ferrous and non-ferrous fractions from end-of-life electronic equipment. Despite the high plastic content and metal value in the ash, high percentages of these materials are currently sent to landfills. In this study, the potential of utilising shredder residue material and other plastic-containing materials as reducing agents was studied. Plastic-containing materials were co-injected with coal into a zinc-fuming furnace in Boliden-Rönnskär smelter. The data obtained from the trial, such as the data from the chemical analysis of the slag and the steam production, are discussed. The observations indicate that plastic-containing material can replace up to 1 ton h−1 of coal without a significant decrease in the zinc reduction rate.
|
|
| 45. |
- Lotfian, Samira, et al.
(författare)
-
Sustainable Management of the Plastic-Rich Fraction of WEEE by Utilization as a Reducing Agent in Metallurgical Processes
- 2019
-
Ingår i: Applied Sciences. - : MDPI. - 2076-3417. ; 9:20
-
Tidskriftsartikel (refereegranskat)abstract
- In modern society, there is a fast growth in the production of electrical and electronic equipment (EEE); however, rapid growth results in the frequent discarding of this equipment. During the treatment of discarded materials, a stream is generated that contains a high fraction of plastic materials, but also metals and oxides. This stream, which is called shredder residue material (SRM), is heterogeneous, which limits its recycling options. Utilizing this material in metallurgical processes allows the plastic fraction to be used as a reductant and energy source and the metallic fraction to be recycled and returned to the production of EEE. The aim of this study was to evaluate the potential of plastic-containing materials, especially SRM, as alternative reductants in metallurgical processes. The first step was to compare the thermal conversion characteristics of plastic-containing materials to the currently used reducing agent, i.e., coal. Three main candidates, polyurethane (PUR), polyethylene (PE), and SRM, were studied using a drop tube furnace and an optical single-particle burner. PE had the highest volatile content and the fastest conversion time, whereas PUR had the longest conversion time. Thereafter, plastic materials were tested at the industrial scale through injection to the zinc fuming process at the Boliden Rönnskär smelter. During the industrial trial, the amount of coal that was injected was reduced and substituted with plastic material. The results indicate the possibility of reducing the coal injection rate in favor of partial substitution with plastic materials.
|
|
| 46. |
- Mareschal, Sylvain, et al.
(författare)
-
Challenging conventional karyotyping by next-generation karyotyping in 281 intensively treated patients with AML
- 2021
-
Ingår i: Blood Advances. - : American Society of Hematology. - 2473-9529 .- 2473-9537. ; 5:4, s. 1003-1016
-
Tidskriftsartikel (refereegranskat)abstract
- Although copy number alterations (CNAs) and translocations constitute the backbone of the diagnosis and prognostication of acute myeloid leukemia (AML), techniques used for their assessment in routine diagnostics have not been reconsidered for decades. We used a combination of 2 next-generation sequencing-based techniques to challenge the currently recommended conventional cytogenetic analysis (CCA), comparing the approaches in a series of 281 intensively treated patients with AML. Shallow whole-genome sequencing (sWGS) outperformed CCA in detecting European Leukemia Net (ELN)-defining CNAs and showed that CCA overestimated monosomies and suboptimally reported karyotype complexity. Still, the concordance between CCA and sWGS for all ELN CNA-related criteria was 94%. Moreover, using in silico dilution, we showed that 1 million reads per patient would be enough to accurately assess ELN-defining CNAs. Total genomic loss, defined as a total loss 200 Mb by sWGS, was found to be a better marker for genetic complexity and poor prognosis compared with the CCA-based definition of complex karyotype. For fusion detection, the concordance between CCA and whole-transcriptome sequencing (WTS) was 99%. WTS had better sensitivity in identifying inv(16) and KMT2A rearrangements while showing limitations in detecting lowly expressed PML-RARA fusions. Ligation-dependent reverse transcription polymerase chain reaction was used for validation and was shown to be a fast and reliable method for fusion detection. We conclude that a next-generation sequencing-based approach can replace conventional CCA for karyotyping, provided that efforts are made to cover lowly expressed fusion transcripts.
|
|
| 47. |
- Miliara, Sophia, et al.
(författare)
-
The biological and prognostic role of long non-coding RNA NEAT1 in acute myeloid leukemia
-
Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Nuclear paraspeckle assembly transcript 1 (NEAT1) is a long non-coding RNA localized in the cell nucleus that has been associated to promote several malignant solid tumors. Its role in acute myeloid leukemia (AML) remains largely elusive. Therefore, the aim of this study was to define the role of NEAT1 in AML compared to normal hematopoiesis. During normal hematopoiesis, it was identified that NEAT1 expression was low in early progenitors but increased in more differentiated cells, especially in monocytes. NEAT1 expression was increased in AML as a whole compared to normal bone marrow (NBM). It was specifically high in AML with inv(16) and t(8;21), while it was lower in patients with t(15;17). Further, NEAT1 expression correlated positively with ASXL1, KRAS and NRAS mutations and negatively with TP53 mutant AML. Higher NEAT expression was associated to better overall survival in AML, independent of other known risk factors. Antisense oligo-mediated knockdown of NEAT1 in AML cells significantly increased expression of the monocytic marker CD14 while granulocytic markers did not change. Genes affected by NEAT1-knockdown using CAGE-sequencing were significantly enriched for genes involved in glucose metabolism. By investigating genome-wide RNA and DNA interactions using RADICL-sequencing, it was revealed that NEAT1 binds to the loci of key hematopoietic regulator RUNX2 as well as the chromatin regulators KMT2A, KMT5B and CHD7. The results suggest that lncRNA NEAT1 has a potential role in hematopoietic and AML cell differentiation and could be a potential new biomarker in AML.
|
|
| 48. |
- Mujahed, Huthayfa, et al.
(författare)
-
AML displays increased CTCF occupancy associated with aberrant gene expression and transcription factor binding
- 2020
-
Ingår i: Blood. - : American Society of Hematology. - 0006-4971 .- 1528-0020. ; 136:3, s. 339-352
-
Tidskriftsartikel (refereegranskat)abstract
- CCTC-binding factor (CTCF) is a key regulator of gene expression through organization of the chromatin structure. Still, it is unclear how CTCF binding is perturbed in leukemia or in cancer in general. We studied CTCF binding by chromatin immunoprecipitation sequencing in cells from patients with acute myeloid leukemia (AML) and in normal bone marrow (NBM) in the context of gene expression, DNA methylation, and azacitidine exposure. CTCF binding was increased in AML compared with NBM. Aberrant CTCF binding was enriched for motifs for key myeloid transcription factors such as CEBPA, PU.1, and RUNX1. AML with TET2 mutations was characterized by a particularly strong gain of CTCF binding, highly enriched for gain in promoter regions, while AML in general was enriched for changes at enhancers. There was a strong anticorrelation between CTCF binding and DNA methylation. Gain of CTCF occupancy was associated with increased gene expression; however, the genomic location (promoter vs distal regions) and enrichment of motifs (for repressing vs activating cofactors) were decisive for the gene expression pattern. Knockdown of CTCF in K562 cells caused loss of CTCF binding and transcriptional repression of genes with changed CTCF binding in AML, as well as loss of RUNX1 binding at RUNX1/CTCF-binding sites. In addition, CTCF knockdown caused increased differentiation. Azacitidine exposure caused major changes in CTCF occupancy in AML patient cells, partly by restoring a CTCF-binding pattern similar to NBM. We conclude that AML displays an aberrant increase in CTCF occupancy that targets key genes for AML development and impacts gene expression.
|
|
| 49. |
- Neddermeyer, Anne, et al.
(författare)
-
A new mutant NPM1/IDH2R140- and PML-RARA-associated lncRNA MALNC plays a role in AML biology, prognosis and drug response
-
Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Acute myeloid leukemia (AML) is a hematopoietic malignancy characterized by poor prognosis that requires better understanding of its disease biology and new tools for suitable risk stratification and effective treatments. Long non-coding RNAs (lncRNAs) are involved in numerous molecular mechanisms, are implicated in tumor biology and can serve as clinical biomarkers, yet their role remains mostly unclear in AML. In this study, the aim was to discover and characterize lncRNAs implicated in AML and to describe their role in AML biology. Further aims were to explore their use as prognostic or predictive biomarkers. Using whole-transcriptome analysis, a novel lncRNA, here named MALNC, was identified. MALNC had elevated expression in two large AML cohorts compared to normal CD34+ cells. Clinical correlation analyses indicated that MALNC was almost uniquely expressed in patients with PML-RARA fusion gene and with co-mutated isocitrate dehydrogenase-2 R140 and nucleophosmin-1 (IDH2R140/NPM1). MALNC expression was specifically high at the promyelocytic stage and decreased with maturation in leukemic and normal cells. High MALNC expression associated independently with better overall survival. CRISPR-Cas9-knockout in promyelocytic cell lines impaired proliferation, colony formation and all-trans retinoic acid (ATRA)-induced differentiation. Also, MALNC-knockout dramatically sensitized cells to arsenic trioxide (ATO), ATO-ATRA combinatorial and Bcl-2-inhibitor venetoclax treatment as well as associated with cyclin-dependent kinase (Cdk)-inhibitor resistance. In conclusion, MALNC is overexpressed in certain subgroups of AML and could play a role during normal and leukemic hematopoietic maturation. Furthermore, it correlates with response to anti-leukemic drugs, which suggests a role as a predictive marker to drug response and survival in AML.
|
|
| 50. |
- Nilsson, Helena Jernmark, et al.
(författare)
-
The transcriptional coregulator NAB2 is a target gene for the Wilms' tumor gene 1 protein (WT1) in leukemic cells
- 2017
-
Ingår i: Oncotarget. - : Impact Journals, LLC. - 1949-2553. ; 8:50, s. 87136-87150
-
Tidskriftsartikel (refereegranskat)abstract
- The Wilms' tumor gene 1 (WT1) is recurrently mutated in acute myeloid leukemia. Mutations and high expression of WT1 associate with a poor prognosis. In mice, WT1 cooperates with the RUNX1/RUNX1T1 (AML1/ETO) fusion gene in the induction of acute leukemia, further emphasizing a role for WT1 in leukemia development. Molecular mechanisms for WT1 are, however, incompletely understood. Here, we identify the transcriptional coregulator NAB2 as a target gene of WT1. Analysis of gene expression profiles of leukemic samples revealed a positive correlation between the expression of WT1 and NAB2, as well as a non-zero partial correlation. Overexpression of WT1 in hematopoietic cells resulted in increased NAB2 levels, while suppression of WT1 decreased NAB2 expression. WT1 bound and transactivated the proximal NAB2 promoter, as shown by ChIP and reporter experiments, respectively. ChIP experiments also revealed that WT1 can recruit NAB2 to the IRF8 promoter, thus modulating the transcriptional activity of WT1, as shown by reporter experiments. Our results implicate NAB2 as a previously unreported target gene of WT1 and that NAB2 acts as a transcriptional cofactor of WT1.
|
|
