| 1. |
- Alvarenga, Rodrigo A.F., et al.
(författare)
-
Towards product-oriented sustainability in the (primary) metal supply sector
- 2019
-
Ingår i: Resources, Conservation and Recycling. - : Elsevier. - 0921-3449 .- 1879-0658. ; 145, s. 40-48
-
Tidskriftsartikel (refereegranskat)abstract
- Consideration of sustainable supply of (primary) metals is increasingly influencing the policy agenda of western societies. Environmental sustainability can be managed from different perspectives, including a site-oriented one (strongly used by the mining sector) and a product-oriented one (as with life cycle assessment). The objectives of this article are to analyse and discuss the differences in these perspectives; to discuss potential benefits to the metal/mining sector of also considering the product-oriented perspective; and to propose ways for a smooth implementation. We made use of literature and expert knowledge, on top of interviews with different stakeholders, to identify why and how these perspectives are (not) used in the metal/mining sector. Moreover, we identified three key concerns related to the implementation of a product-oriented perspective in the sector (e.g., use of unrepresentative life cycle inventory (LCI) datasets for metal-based products) and proposed three corrective actions for all of them (e.g., increase the quantity and quality of LCI). Finally, we discuss how the corrective actions could be implemented in the sector in a smooth way and some potential benefits from its implementation.
|
|
| 2. |
|
|
| 3. |
- Fettweis, Reginald, et al.
(författare)
-
The new Vindelgransele gold ore domain, northern Sweden; preliminary results from the Fabodtjarn lode gold deposit
- 2017
-
Ingår i: Mineral Resources to Discover. - : Society for Geology Applied to Mineral Deposits. - 9782981689801 ; , s. 139-142
-
Konferensbidrag (refereegranskat)abstract
- The Fabodtjarn lode gold deposit is located in the Vindelgransele area, in the Skellefte District, in northern Sweden. The mineralization consists of a quartz vein system hosted in a sequence of turbiditic greywackes and pelitic sedimentary rocks, situated 20-30 meters above the contact with a granodiorite sill. The aim of the study is to better understand the genesis and controls on ore at Fabodtjarn and improve exploration guides for the area. Gold deposits have been known in the Skellefte District for over a century. However, there is an ongoing debate whether some of these deposits are intrusion-related or orogenic gold. Several gold deposits in the Vindelgransele area are spatially associated with intrusive rocks. There might thus be a genetic link between the Fabodtjarn deposit and the intrusion, or the intrusive rocks have simply acted as structural traps during compressional stress conditions.
|
|
| 4. |
- Garcia Uriarte, Ainara, et al.
(författare)
-
SUstainable management of PRIMary raw materials through a better approach in Life Cycle Sustainability Assessment (SUPRIM)
- 2019
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The project focuses on the assessment of the environmental impact of raw materials production and the development of services to better understand sustainability issues in the sector. The main objectives of the project are:• Development of a Life Cycle Impact Assessment (LCIA) method to address resource accessibility in sustainability assessment and testing and validatingthe method.• Development of Life Cycle Inventory (LCI) datasets through case studies in collaboration with the industrial partners from the mining sector and apply anenvironmental assessment with the aim to better understand the environmental impacts of the production of copper and the sources of these impacts.• Bring the service to a broader audience, including the LCIA community, mining companies and their downstream users, policy makers, academia.Two case studies have been performed, the Cobre las Cruces mine in Spain, operated by First Quantum Minerals Ltd, as well as the Aitik mining operation innorthern Sweden, operated by Boliden Mineral AB.
|
|
| 5. |
- Hamberg, Roger, et al.
(författare)
-
Release of arsenic from cyanidation tailings
- 2016
-
Ingår i: Minerals Engineering. - : Elsevier BV. - 0892-6875 .- 1872-9444. ; 93, s. 57-64
-
Tidskriftsartikel (refereegranskat)abstract
- At a gold mine in northern Sweden, gold occurring as inclusions in pyrrhotite and arsenopyrite is leached by cyanidation of the ore. The main sulphide minerals in the ore are pyrrhotite and arsenopyrite. Effluents from the cyanidation process are treated with Fe2(SO4)3 to form Fe-precipitates suitable for the co-precipitation of As. The aim of this study was to perform static and kinetic leaching tests on the ore and tailings to define geochemical processes governing As mobility. Sequential leaching tests suggested that the majority of dissolved As deriving from the sulphide fraction in the ore was incorporated in newly formed Fe-precipitates in the tailings. The mobility of As in the tailings was therefore mainly dependent on the stability of these As-bearing Fe-precipitates. Weathering cell tests (WCT) involving 31 weekly cycles of wetting and air exposure were conducted to assess the stability of the As in the tailings under accelerated weathering conditions. The first stage of the WCT was characterized by a pH ≈ 5 and low As leaching, probably driven by the dissolution of amorphous Fe-As species. In the second stage of the WCT, leaching of Fe, S and As increased and the pH decreased to <3.5. An increase of the leachate’s molar Fe/S-ratio suggested that pyrrhotite oxidation was occurring. The falling pH destabilized As-bearing Fe-precipitates, causing further As release. The total As release during the WCT corresponded to only a small proportion of the tailings’ total As content. The accelerated As-leaching observed towards the end of the WCT could thus indicate that its release could increase progressively over time.
|
|
| 6. |
- Riegler, Thomas, et al.
(författare)
-
Petrographic and mineralogical study of the Kilmacoo gold occurrence, Avoca District, Southeast Ireland
- 2019
-
Ingår i: Proceedings of the 15th SGA Biennial Meeting, 27-30 August. - : University of Glasgow Publicity Services. ; , s. 323-326
-
Konferensbidrag (refereegranskat)abstract
- Petrographic investigation of the quartz vein hosted Kilmacoo gold occurrence spatially associated with the copper rich Avoca massive sulphide ore body evidenced a close association between gold and sulphides. Visible electrum grains are frequently observed within chalcopyrite, and more rarely as minute inclusions in both arsenopyrite and pyrite. Mineralogical investigations also revealed complex sulphide paragenetic succession from framboidal pyrite to colloform and idiomorphic cements with overall a low arsenopyrite content. We also documented the presence of hydrothermal phosphates (apatite and monazite) subsequently altered in aluminum phosphate sulphate minerals, as well as a broad diversity of phyllosilicates. These observations as well as the cross cutting relationships tend to indicate a brittle deformation event involving possible remobilization of some of the copper mineralization from the main VMS ore body. At the present time the source of gold is still under investigation to determine the possible contribution from both local and distal sources.
|
|
| 7. |
- Thomas, Helen V., et al.
(författare)
-
Mineralization, alteration and age of the host at the Barsele orogenic gold deposit, northern Sweden
- 2019
-
Ingår i: Proceedings of the 15th SGA Biennial Meeting, 27-30. - : University of Glasgow Publicity Services. ; , s. 707-710
-
Konferensbidrag (refereegranskat)abstract
- The Barsele Gold deposit is located near Storuman in Northern Sweden. Mineralization is hosted in approximately N-S to NW-SE trending D3 oriented quartz-carbonate veins and microfractures located in a granodiorite intrusion dated at 1.872 Ga +/- 11 Ma by this study. Gold is primarily free milling with a minor proportion occurring as invisible gold associated with sulphide minerals.
|
|
| 8. |
- Warlo, Mathis, et al.
(författare)
-
Automated quantitative mineralogy optimized for simultaneous detection of (precious/critical) rare metals and base metals in a production-focused environment
- 2019
-
Ingår i: Minerals. - : MDPI. - 2075-163X. ; 9:7
-
Tidskriftsartikel (refereegranskat)abstract
- Automated Scanning Electron Microscopy (ASEM) systems are applied in the mining industry to quantify the mineralogy of the ore feed and products. With society pushing towards sustainable mining, this quantification should be comprehensive and include trace minerals since they are often either deleterious or potential by-products. Systems like QEMSCAN® offer a mode for trace mineral analysis (TMS mode); However, it is unsuitable when all phases require analysis. Here, we investigate the potential of detecting micron-sized trace minerals in fieldscan mode using the QEMSCAN® system with analytical settings in line with the mining industry. For quality comparison, analysis was performed at a mining company and a research institution. This novel approach was done in full collaboration with both parties. Results show that the resolution of trace minerals at or below the scan resolution is difficult and not always reliable due to mixed X-ray signals. However, by modification of the species identification protocol (SIP), quantification is achievable, although verification by SEM-EDS is recommended. As an add-on to routine quantitative analysis focused on major ore minerals, this method can produce quantitative data and information on mineral association for trace minerals of precious and critical metals which may be potential by-products in a mining operation
|
|
| 9. |
- Warlo, Mathis, et al.
(författare)
-
Gold and silver mineralogy of the Liikavaara Cu-(W-Au) deposit, northern Sweden
- 2019
-
Ingår i: Proceedings of the 15th SGA Biennial Meeting, 27-30 August 2019, Glasgow, Scotland. - : Society for Geology Applied to Mineral Deposits. ; , s. 1532-1535
-
Konferensbidrag (refereegranskat)abstract
- The Liikavaara Cu-(W-Au) deposit in northern Sweden is scheduled for production by the mining company Boliden AB in 2023. The ore will be processed in the plant of the nearby Aitik Cu-Au deposit. Copper will be the primary product and the trace metals Au andAg will be byproducts.The trace mineralogy of Liikavaara, however, differs from that of Aitik and this might have implications on the mineral processing and recovery efficiency. Gold occurs mostly as free <10μm-sized grains of native Au and electrum. Some Au is associated with native Bi, typically in <5μm Bi-melt drops. Gold grains commonly form inclusions in quartz and sulfide minerals. Silver is found in electrum, hessite and acanthite. Hessite is the most abundant Ag mineral and it is commonly intergrown with pilsenite. Similar to Au, inclusions and crack-fillings of Ag in sulfides and quartz are most prominent. The small grain size, the diverse mineralogy, the association with Bi-phases, and the occurrence as inclusions in quartz may lower the recovery of Au and Ag in Liikavaara compared to Aitik, where Au and Ag phases are mostly bound in sulfides. Hence, adaptation of the processing parameters may be necessary in order to increase recovery of Au and Ag from the Liikavaara ore.
|
|
| 10. |
- Warlo, Mathis
(författare)
-
Improving trace metal characterisation of ore deposits – a crucial step towards sustainable mining
- 2019
-
Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Sustainable mining, including the utilisation of an ore body to its full potential, is becoming increasingly important for human society as the demand for metals increases. In order to maximise the recovery of useful metals, detailed characterisation of the ore prior to processing is vital. Characterisation should include major and minor ore minerals, gangue minerals, and also trace metals. Trace metals despite their low abundance are often particularly important, either due to their high economic value and criticality for society, or their negative impact on the quality of the main commodity recovered and/or the environment. To properly characterise trace metals in an ore deposit the use of micro-analytical techniques is necessary. Nowadays, a plethora of techniques exist, each with their own strengths and weaknesses. In the mining industry, automated scanning electron microscopy systems are widely used. These systems allow for rapid mineralogical characterisation and quantification of a sample and are commonly used to quantify the mineralogy of the ore feed and subsequent products. Operators of these systems benefit from prior knowledge of the mineralogy of a sample/deposit to fine-tune their processing software to deliver data of highest quality. In this study, a method to improve trace metal characterisation in ore deposits with automated scanning electron microscopy systems is presented. It is implemented as a case study on the Liikavaara Cu-(W-Au) deposit in northern Sweden. The deposit is enriched in several trace metals including Au, Ag, Bi and Sn, and is planned for production in 2023. The mine will produce Cu as the main product and Au and Ag as by-products, and the processing of the ore will be performed in the nearby Aitik plant. For this study, a detailed geological and mineralogical investigation of the deposit was performed prior to analysis with the automated scanning electron microscopy system. A good understanding of the mineralogy is necessary to be able to select a representative sample for the subsequent automated analysis and to guarantee optimal data quality produced by the automated system, and to judge the performance of the automated system, to improve the method of analysis.Manuscript 1 deals with the geological description and genetic aspects of the Liikavaara ore deposit. Results indicate that Liikavaara is an intrusion-related vein-style deposit. Mineralisation is hosted by quartz-tourmaline and calcite veins in a metadiabase that is partly metamorphosed to biotite schist. A 1.87 Ga granodiorite intrudes the footwall. Aplite dikes, genetically related to the intrusion, crosscut the metadiabase host rock. Mineralised veins are concentrated in and around these dikes.Manuscript 2 deals with method development of automated mineralogical analysis. A sample from a mineralised quartz-tourmaline vein at Liikavaara was analysed in great detail with the QEMSCAN® system. Apart from ore minerals in major and minor abundance the sample also contains ore minerals in trace quantities, e.g. Au and Ag minerals. The sample was analysed using two different analytical settings, at two different laboratories, one typical of a production-focused industrial approach and one quality-focused scientific approach. A first analysis using the industrial approach was unable to detect any Au and Ag minerals in the sample. By modification of the QEMSCAN® mineral reference library, through iterative use of the data from both the industrial- and the scientific approach, detection and quantification of Au and Ag minerals was successful. This method can be implemented as an add-on for routine industrial analysis by automated scanning electron microscopy systems to gain information on trace metal occurrence and distribution. This information can then be used for targeted sample selection for further in-depth analysis of the trace metal content and occurrence in the deposit.
|
|
