Lithological core logging is a subjective and time consuming endeavour which could possibly be automated, the question is if and to what extent this automation would affect the resulting core logs. This study presents a case from the Zinkgruvan Zn-Pb-Ag mine, Bergslagen, Sweden; in which Classification and Regression Trees and K-means Clustering on the Self Organising Map were applied to X-Ray Flourescence lithogeochemistry data derived from automated core scan technology. These two methods are assessed through comparison to manual core logging. It is found that the X-Ray Fluorescence data are not sufficiently accurate or precise for the purpose of automated full lithological classification since not all elements are successfully quantified. Furthermore, not all lithologies are possible to distinquish with lithogeochemsitry alone furter hindering the success of automated lithological classification. This study concludes that; 1) K-means on the Self Organising Map is the most successful approach, however; this may be influenced by the method of domain validation, 2) the choice of ground truth for learning is important for both supervised learning and the assessment of machine learning accuracy and 3) geology, data resolution and choice of elements are important parameters for machine learning. Both the supervised method of Classification and Regression Trees and the unsupervised method of K-means clustering applied to Self Organising Maps show potential to assist core logging procedures.

Inthe mining industry people remove rock from the ground to obtain a metal ore. Afterprocessing , the uneconomic fraction called tailings is deposited as a slurry in large reservoirs .The processing adds water and chemical agents to the tailings so that the original structure ofthe material therefore changes, which make storage of tailings complicated. If a tailingreservoir c ollapse s , it can damage p roperties and life downstream . In addition, tailings maycontain contaminants that disturb living organism s and contaminated groundwater in the localarea even under normal operation s . Therefore, tracing the contaminants and study ing thestability of the tailing reservoir s are important. The aim of the thesis is to investigate seepage,contaminant transport, tailings compaction and slope stability of the Zhaoli ditch tailingsreservoir (China) during its construction and afterwards. Simulations are performed with thecomputer program GeoStudio . According to the simulations and the conditions , contaminanttransport was highly related with total head. Total head boundary conditi ons have also a largeeffect on slope stability. The area that has most vertical displacement is at the middle of thetailing s reservoir , and the greatest change of vertical displacement is located near the slope,w here the vertical displacement can increa se 0.5 meter over a 1 0 30 meter distance. Theslope stability can be different from case to case, but the original designed tailing reservoirhave a good safety factor, indicating that the slope is not going to collapse easily. / Vi människor villutnyttja malm erna i marken för att skapa ett mer effektiv t industrisamhälleF ör att utvinna så myck et användbara metaller som möjligt tillsätts kemika lier och vattenunder anriknings processen, vilket gör att deponering av de vattenmättade restprodukt erna isandmagasin blir en utmaning med avseende på dammstabilitet och föroreningstransport.Eftersomdet är svårt att ändra på en färdig byggd damm för anrikningssand e n använder dettaexamensarbete av Geostudio för att simulera hur olika parameter påverkaföroreningstransport i dammen, vattenläckage från dammen samt da mmens stabilitet ochsäkerhet. Projektet har simulerat förhållanden i Zhaoli ditch damm i Kina .Simulering i GeoStudio visar att förorening sspridning är stark kopplad till den totalahydrauliska potentialen och materialets hydrauliska konduktivitet. Rand villkoren medavseende på den hydrauliska potentialen utanför dammen även har en stor inverkan pådammvallens stabilitet. De största vertikala sättningar sker i mitten av dammen, och denstörste sättningsgradient finns i dammvallens sluttning, där en vertikal sättning på 0.5 meteröver ett avstånd på 10 3 0 meter beräknas. Deformation är störst på första lagret överberggrunden. Simuleringarna visar att dammvallens sluttning är stab il med en tillräcklig högsäkerhetsfaktor.

Background: The Digital Twin is an increasingly trending technology that utilizes many of the key technologies relevant to the digitalization of industries and Industry 4.0, such as AI, Big Data, and IoT, to bring a virtual asset and a physical asset together to perform analysis and execute real-time decision making backed up by data (Grieves & Vickers, 2017; Rasheed et al., 2020). Current research on the benefits and challenges of Digital Twins in process industries is sparse and under-developed, and the significance of Digital Twins in their operational lifecycle phase requires investigation (Perno et al., 2020; Schleich et al., 2019; Sjödin, 2013). Research Questions: RQ1: What are the benefits of industrial process plant Digital Twins for companies in process industries? RQ2: What are the challenges that companies will face with industrial process plant Digital Twins in process industries? Literature Review: A theoretical framework was developed based on the applications, challenges, and enablers researched in other industries which acted as a foundation for the data collection process. Research Method: The thesis follows a qualitative research approach. A single-case study was employed with a large equipment supplier in the mineral processing industry, where data was collected through 17 semi-structured interviews with people possessing in-depth knowledge about the needs of the mineral processing industry. Findings: Five main benefits of industrial process plant Digital Twins in process industries were identified, Process performance, Monitoring and control, Predictive maintenance and scheduling, Business opportunities, and Safety. Correspondingly, four main challenges were identified, Perception and presentation, Privacy and security, Data management and performance, and Mutual scope and focus. Conclusions: The thesis project's managerial and theoretical implications include providing equipment suppliers in process industries with what benefits there lie with industrial process plant Digital Twins and which challenges must be overcome. By providing these benefits and challenges to equipment suppliers, they can prioritize which of these are most important to consider in their situation. The thesis contributes to the research of Digital Twins and adds to the sparse existing knowledge of what the benefits and challenges are of industrial process plant Digital Twins in process industries. The main limitation is the absence of process plant companies during the data collection phase.

Roterugnar är cylindriska kärl som används för att höja materials temperaturer i en kontinuerlig process som kallas för kalcinering. Roterugnar kan tillämpas i olika processer såsom reduktion av oxidmalm samt återvinning av farligt avfall. Fördelen med roterugnar ligger i dess förmåga att hantera råmaterial som sträcker sig från slam till granulära material med en mängd olika partikelstorlekar, och därigenom upprätthålla distinkta miljöer såsom en bädd av fasta partiklar som samexisterar med ett oxiderande fribord. Sex olika bäddbeteende har dokumenterats med avseende på fyllningsgrad samt Froude nummer. Syftet med denna studie var att utveckla en tvådimensionell suspensions modell med CFD genom att använda den kommersiella mjukvaran COMSOL 5.5 för att simulera de två faser, gas och fast, som en blandad fas efter verk av Philips et. al., Physics of Fluids A: Fluid Dynamics 4.1 (1992) 30-40 och Acrivos & Zhang., International Journal Multiphase Flow 20.3 (1994) 579-591. Denna modell undersöktes genom att jämföra den med de dokumenterade flödesregimerna samt genom parameter som partikelstorlek, partikeldensitet och viskositeten hos gas i flödesregimen känd som rullande läge. Dessutom undersöktes temperaturprofilen för den roterande ugnen genom att utforska hur blandningsvariationer av den fasta bädden i den roterande ugnen påverkas av värmeöverföringen när värme tillförs från väggen under rullande läge. Resultaten av den tvådimensionella suspension modellen visade att det var bara möjligt att simulera glidläge korrekt; andra lägen kunde inte beskrivas som dokumenterat i litteraturen. Det indikeras att vilovinkeln och viskösa krafter i den roterande ugnen var låga vilket resulterade i att suspensions modellen inte kunde avbilda exakt de återstående flödesregimerna som dokumenterat. Till exempel avbildades rullningsläget mer likt forsandeläge då partiklarna fall fritt efter höjning av bädden. Partikelstorlek och partikeldensitet har visat sig ha en betydande påverkan på suspensions modellen eftersom de viskösa krafterna blir låga för en partikelstorlek och partikeldensitet under 0,4 mm respektive 1500 kg/m3. Angående gasens viskositet visades det sig att ju närmare värdet 2.055e-3 (Pa*s) den blev desto större blev sedimentationsflödet vilket resulterade i att bäddpartiklarna dras ner och förblir där. Suspensions modellen kunde således simulera en fast och flytande fas och inte en gasfas som avsett. Slutligen visade temperaturanalysen att påverkan av den termiska konduktiviteten var mer signifikant än den specifika värmekapaciteten i intervallet 1 - 50 (W/(m*K)) respektive 300 - 800 (J/(kg*K)) på grund av den tid det tog att nå en homogen temperaturprofil. / Rotary kilns are cylindrical vessels used to raise materials temperature in a continuous process known as calcination. Rotary kilns find application in various processes such as reduction of oxide ore and hazardous waste reclamation. The advantage of the rotary kiln lies in its ability to handle feedstock ranging from slurries to granular materials with a variety of particle size, thereby maintaining distinct environments such as a bed of solid particles coexisting with an oxidising freeboard. Six different bed behaviours within the kiln have been documented with respect to the filling degree and Froude number. The aim of this study was to develop a two-dimensional suspension model with CFD by using the commercial software COMSOL 5.5 to simulate the two phases, gas and solid, as a mixed phase, following the works of Philips et. al., Physics of Fluids A:  Fluid Dynamics 4.1 (1992) 30-40 and Acrivos & Zhang., International Journal Multiphase Flow 20.3 (1994) 579-591. This model was investigated by comparing it against the documented flow regimes as well as through parameters such as particle size, particle density and viscosity of gas in the flow regime known as rolling mode. In addition, the temperature profile of the rotary kiln was investigated by exploring how the mixture variation of the solid bed within the rotary kiln affects the heat transfer when heat is supplied from the wall during a rolling mode. The results of the two-dimensional suspension model showed that it was only possible to simulate the slipping mode accurately; others mode could not be described as documented in literature. It is indicated that the angle of repose and viscous forces within the rotary kiln were low resulting in the suspension model not being able to accurately depict the remaining flow regimes as documented. For instance, the rolling mode was depicted more as a cataracting mode due to the free fall of particles after elevation of the bed. The particle size and the particle density were found to have a significant impact on the suspension model as the viscous forces became low for a particle size and particle density below 0.4 mm and 1500 kg/m3 respectively. As for the viscosity of gas it was found that the closer it got to the value 2.055e-3 (Pa*s) the sedimentation flux became too large resulting in the bed particles being pulled down and remaining there. Thus, the suspension model could simulate a solid and liquid phase and not a gas phase as intended. Lastly, the temperature analysis revealed that the impact of the thermal conductivity was more significant than the specific heat capacity in the range of 1 - 50 (W/(m*K)) and 300 - 800 (J/(kg*K)) respectively, due to the time it took to reach a homogeneous temperature profile.

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