[report] Kemian tekniikan korkeakoulu / CHEM
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Item Raspberry Pi AWB determination methods and their statistical analyses(Aalto University, 2023) Miikki, Kim; Kemian laitos; Department of Chemistry; Kemian tekniikan korkeakoulu; School of Chemical TechnologyThe determination of a correct auto white balance (AWB) parameters in photography are essential for good color reproducibility and invariance in the same lightning conditions. The easiest way to determine AWB gains is to read the camera's AWB gain values. However, this paper demonstrates that the gray card calibration method is more accurate than the built-in AWB method. The major disadvantage of gray card calibration is the time consumption compared to an AWB reading. Two optimized gray card calibration methods are also presented as a much faster methods than the traditional and slow exhaustive search method.Item BIWIC 2022 : 27th International workshop on industrial crystallization : 31 August – 2 September, 20022, Aalto University, Finland(Aalto University, 2022) Ila, Mitra (editor); Louhi-Kultanen, Marjatta (editor); Kemian laitos; Department of Chemistry; Kemian tekniikan korkeakoulu; School of Chemical TechnologyThe 27th International Workshop on Industrial Crystallization (BIWIC 2022) was hosted at Aalto University as an in-person event after a two-year delay due to the COVID-19 pandemic. BIWIC is an international conference that brings researchers and engineers from academia and industry together to discuss latest discoveries and challenges in industrial crystallization. The BIWIC 2022 workshop addressed and promoted discussion on the role of industrial crystallization with special emphasize on circular economy and bioeconomy.Item Properties of the liquid miscibility gap in the system Cu-Cu2S(Aalto University, 2012) Forsström, Antti; Taskinen, Pekka; Johto, Hannu; Materiaalitekniikan laitos; Department of Materials Science and Engineering; Kemian tekniikan korkeakoulu; School of Chemical TechnologyItem International Hydrometallurgy Symposium in Honor of Professor Olof Forsén, 2-3 November 2015, Aalto University, Espoo, Finland(Aalto University, 2015) Seisko, Sipi; Aromaa, Jari; Lundström, Mari (editors); Materiaalitekniikan laitos; Department of Materials Science and Engineering; Kemian tekniikan korkeakoulu; School of Chemical TechnologyItem Cellulose materials doctoral students summer conference 2015(Aalto University, 2015) Hauhio, Leena (editor); Puunjalostustekniikan laitos; Department of Forest Products Technology; Kemian tekniikan korkeakoulu; School of Chemical TechnologyItem Cellulose materials doctoral students summer conference 2014(Aalto University, 2014) unknown; Hauhio, Leena (graphic design); Puunjalostustekniikan laitos; Department of Forest Products Technology; Kemian tekniikan korkeakoulu; School of Chemical TechnologyItem MT-0.3201 : Materials production and synthesis / 2014(Aalto University, 2014) Kekkonen, Marko (ed.); Materiaalitekniikan laitos; Department of Materials Science and Engineering; Kemian tekniikan korkeakoulu; School of Chemical TechnologyItem Teollisuuden ympäristöasioiden hallinta(Aalto University, 2013) Laukkanen, Timo; Dahl, Olli Martikka, Mikko; Puunjalostustekniikan laitos; Department of Forest Products Technology; Kemian tekniikan korkeakoulu; School of Chemical TechnologyItem Materials production and synthesis/ 2013 : MT-0.3201(Aalto University, 2013) Kekkonen, Marko (ed.); Materiaalitekniikan laitos; Department of Materials Science and Engineering; Kemian tekniikan korkeakoulu; School of Chemical TechnologyItem European Forest Products Doctoral Symposium 2013(Aalto University, 2013) Järvelä, Heli (graphic design); Puunjalostustekniikan laitos; Department of Forest Products Technology; Kemian tekniikan korkeakoulu; School of Chemical TechnologyItem Teräskennorakenteiden korroosio merivedessä(Aalto University, 2011) Aromaa, Jari; Leino, Jaakko; Pehkonen, Antero; Virtanen, Jorma; Materiaalitekniikan laitos; Department of Materials Science and Engineering; Kemian tekniikan korkeakoulu; School of Chemical TechnologyItem ACTIVITY REPORT 2007 - 2010(Aalto University, 2011) Jämsä-Jounela, S.-L.; Kämpe, J.; Räisänen, A.; Biotekniikan ja kemian tekniikan laitos; Department of Biotechnology and Chemical Technology; Kemian tekniikan korkeakoulu; School of Chemical TechnologyAalto University School of Science and Technology is the largest and oldest institute of engineering education in Finland. The University campus is situated about 10 km west of Helsinki in the Otaniemi area, in the township of Espoo. The number of undergraduates is about 12 000 and that of postgraduates about 2800. The degrees offered in the School of Science and Technology are the basic Master’s degree in engineering, architecture or landscape-architecture (minimum 4.5 years) and the postgraduate degree Doctor of Technology (minimum 4 years). The Department of Biotechnology and Chemical Technology comprises eight research groups (= eight full professorships): Biochemistry, Microbiology, Bioprocess Technology, Chemical Engineering, Plant Design, Industrial Chemistry, Polymer Technology and Process Control. The Laboratory of Process Control and Automation, as a member of the department was founded in 1987. The aim of the laboratory is to serve all fields of process technology - chemical, metallurgical and forest products - in terms of process automation. The laboratory gives courses in process modelling, simulation, control, optimization and automation as well as in production control. The undergraduate students typically have a few years background of process engineering studies, after which a one-to-two-year portion of automation studies. Post-graduate students typically work in the field of process technology - either in the industry or in research institutes or universities - while studying. This report describes briefly the staff, teaching, facilities, research and other activities of the Laboratory of Process Control and Automation during 2007 - 2010.Item MT-0.3201 : materials production and synthesis / 2011(Aalto University, 2011) Kekkonen, Marko (editor); Materiaalitekniikan laitos; Department of Materials Science and Engineering; Kemian tekniikan korkeakoulu; School of Chemical TechnologyItem Densities of Molten and Solid Alloys of (Fe, Cu, Ni, Co)-S at Elevated Temperatures - Literature Review and Analysis(Aalto University Publications in Materials Science and Engineering, 2010) Tesfaye, Fiseha; Taskinen, Pekka; Materiaalitekniikan laitos; Department of Materials Science and Engineering; Metallurgical Thermodynamics and Modelling Research Group; Metallurgisten prosessien termodynamiikan ja mallinnuksen tutkimusryhmä; Kemian tekniikan korkeakoulu; School of Chemical TechnologyDensities of solid and liquid Fe, Cu, Ni and Co, and their alloys both at the presence and absence of sulfur have been reviewed. Volumetric thermal expansions were used to estimate the densities at different temperatures. Densities of the alloys generally decrease with increasing temperature. For the pure metals the reduction in density as temperature rises from 25 oC to their respective melting point can be estimated to be about 7.05 ± 0.4 % just before melting and about 11.63 ± 0.92 on complete melting. According to the literature data and the analyzed results, at ambient pressure condition, density of the stoichiometric FeS changes from 4.615 g/cm3 at 25 oC to 3.8 g/cm3 at 1200 oC (17.7 %), density of the stoichiometric Cu2S changes from 5.65 g/cm3 at 25 oC to 5.18 g/cm3 at 1200 oC (8.3 %), density of the stoichiometric NiS changes from 5.5 g/cm3 at 25 oC to 5.025 g/cm3 at 1027 oC (8.5 ± 1.8 %) and density of the stoichiometric CoS changes from 5.45 g/cm3 at 25 oC to 4.88 g/cm3 at 1100 oC (10.45 %). A study on the Fe-S melts at 4GPa suggests that in sulfur-poor compositions, where solubility of sulfur is less likely to be affected by pressure, the density of the sulfides at isothermal conditions decreases in a similar fashion as under 1 bar, i.e., density decreases non-linearly with increasing composition of sulfur.Item Sulfide Mineralogy - Literature Review(Aalto University, 2010) Tesfaye, Fiseha; Taskinen, Pekka; Materiaalitekniikan laitos; Department of Materials Science and Engineering; Metallurgical Thermodynamics and Modeling Research Group; Metallurgisten prosessien termodynamiikka ja mallinnus; Kemian tekniikan korkeakoulu; School of Chemical TechnologyThe aim of this study was to have an insight into the sulfide mineralogy, mainly based on sulfides mineralogical studies prior to the year 1975. In the first two chapters, the metal sulfides crystal structures and chemistries are reviewed. Then, the electronic interactions and chemical bonding followed by experimental methods in sulfides research with the proposed phase equilibria are reviewed. Phase relations in the (Cu, Ni, Zn)-S systems are discussed. Due to its influential and common appearance, in most natural sulfides (the common rock-forming minerals: po and py), the Fe-S system has been summarized relatively in detail. Sulfide petrology has been also discussed. The metal sulfides are the raw materials for most of the world supplies of non-ferrous metals. Their complex chemistry, as a result of high impurities association (such as As, Sb, Bi, etc...) and less base-metals content (metal poor rocks: composition of base-metal is less than 1 at.%), and the ever growing demand for the metals as well as the embroiling need to optimize minerals processing and sulfides smelting claim intense mineralogical studies. The main goal of such studies are to acquire accurate thermodynamic data which are useful to predict reactions and stable relationships, and in defining the limiting conditions under which phases may exist.Item Thernmodynamics and Phase Equilibria in the (Ni, Cu, Zn)-(As, Sb, Bi)-S Systems at Elevated Temperature (300-900 C)(Aalto University, 2010) Tesfaye, Fiseha; Taskinen, Pekka; Materiaalitekniikan laitos; Department of Materials Science and Engineering; Metallurgical Thermodynamics and Modeling Research Group; Metallurgisten prosessien termodynamiikka ja mallinnus; Kemian tekniikan korkeakoulu; School of Chemical TechnologyStable phase relations in the (Ni, Cu)-(As, Sb)-S, Cu-Bi-S and Zn-As-S systems and their thermodynamic properties, at the presence of the impurities, are reviewed. The Cu-based systems are relatively intensively studied. Among the sulfosalts of these systems tetrahedrite (Cu12+xSb4+yS13, where 0 < x < 1.92 and -0.02 < y < 0.27) and tennantite (Cu12+xAs4+yS13, where 0 < x < 1.72 and 0 < y < 0.08) are reported to be the most stable relative to other sulfosalts and certain other sulfide phases, which accounts for their common occurrence in a variety of mineral ore deposits. Natural tetrahedrite and tennantite in equilibrium with other minerals commonly constitute other chemical elements as a substitution for Cu, As and Sb and both are described by the general formula:(Cu, Ag)10(Fe, Zn, Cu, Hg, Cd, Co, Au)2(Sb, As)4S13. According to the literature data the Ni-based systems comprise a single stoichiometric ternary stable phase for their respective impurities (gersdorffite, NiAsS, and ullmannite, NiSbS), and both experience a wide solid solubility range. At favorable conditions substitution of As for S in the gersdorffite and Co for Ni and Sb for As in the ullmennite are the main mechanisms of solid solution formations. Thermodynamic properties and phase equilibria studies in the Zn-As-S system are rare among published litrature. A study about this system, below 760 oC, has shown that there is no ternary phase stable. In general, the ternary systems have complex phase relations, which may be as a result of the very low differences in their Gibbs energies of formation.Item A thermodynamic assessment of the BaO-MgO, BaO-CaO, BaO-Al2O3 and BaO-SiO2 systems(Aalto University, 2014) Zhang, Rui; Taskinen, Pekka; Materiaalitekniikan laitos; Department of Materials Science and Engineering; Thermodynamic and Modelling of Metallurgical Processes; Kemiantekniikan korkeakoulu; School of Chemical TechnologyLiterature data concerning thermodynamic data for BaO including melting point, heat capacity, enthalpy increment, enthalpy of formation and entropy of formation were reviewed. The phase diagram data of the BaO-MgO, BaO-CaO, BaO-Al2O3 and BaO-SiO2 systems were evaluated and taken into account in the thermodynamic assessment in the present work. Associate model was employed to describe the liquid phase in the BaO-Al2O3 and BaO-SiO2 systems. Four sets of consistent thermodynamic parameters, which can explain most of the experimental data of the BaO-MgO, BaO-CaO, BaO-Al2O3 and BaO-SiO2 systems, were achieved. The calculated phase diagrams of BaO-MgO, BaO-CaO, BaO-Al2O3 and BaO-SiO2 systems were provided. By employing the optimized thermodynamic parameters, mixing of enthalpies of the liquid phase for the four systems and heat capacities for BaAl2O4 and BaAl12O19 were calculated and compared with the literature values.Item Korroosion ja korroosioneston historia(Aalto University, 2013) Aromaa, Jari; Materiaalitekniikan laitos; Department of Materials Science and Engineering; Korroosio ja hydrometallurgia; Kemian tekniikan korkeakoulu; School of Chemical TechnologyKorroosio on teknologian alue, joka käsittelee materiaaleja, ympäristöjä ja niiden vuorovaikutusta, ja jonka painotus on teknisten ratkaisujen toiminnan varmistamisessa. Korroosio alkoi aiheuttaa ongelmia teknisissä ratkaisuissa jo 1400-1600-luvuilla. Korroosion vaarallisia vaikutuksia ei havaittu, ennen kuin metalleja alettiin käyttää runsaasti rakenteisiin, koneisiin ja laitteisiin. Korroosion yleistyminen ja korroosionestomenetelmien kehittämisen alku ajoittuvat 1850-luvulle. Jo 1900-luvun alussa oltiin huolestuneita rautamalmien riittävyydestä, koska yhä suurempi osa teräsrakenteista tuhoutui korroosion takia. Yhdysvalloissa vuosina 1999-2001 tehdyn arvion mukaan suorat korroosiokustannukset olivat 3,2 % bruttokansantuotteesta ja epäsuorat ainakin yhtä suuret. Vakavia onnettomuuksia, joissa korroosio on ollut merkittävä tekijä, on ollut useita. Tämä kirjallisuustutkimus on katsaus poikkitieteellisen tekniikan alan teorian ja ajattelutapojen kehittymisestä nykytilaansa.Item Hydrometallurgical recovery of platinum group metals(Aalto University, 2012) Lillkung, Kristian; Aromaa, Jari; Materiaalitekniikan laitos; Department of Materials Science and Engineering; Corrosion and Hydrometallurgy; Korroosio ja hydrometallurgia; Kemian tekniikan korkeakoulu; School of Chemical TechnologyThe demand for platinum group metals (PGMs) has been rising significantly for the last few decades as the metals have become very important for the today’s society. They are used in pollution control and also in many other applications where their unique properties are needed. It seems that the trend is towards even further increase in the consumption due to tightening emission standards and new energy sources. The supply of PGMs is limited as they only exist in a larger scale in South Africa and Russia. As the end products where PGMs are used are scattered around the globe, the recycling of the metals at these locations also seems attractive. This literature review focuses on the extraction and separation processes used in the platinum group metals industry nowadays. The information available is partly limited as companies are not willing to give their secrets away. Most of the processes reviewed are meant for primary metals processing, but some of them are also used to recycle PGMs from secondary sources. The number of specific processes proposed in the literature is high, but most of these processes are however mainly modifications from existing processes and based on the same principles. Differences in the used raw material lead to clear differences in the used process chemistry and technology when producing platinum group metals. As more metals are present, usually a more complex process chain has to be utilized. The process chemistry has to adapt easily to small changes in order to make the process profitable. In this report some of the commercially available processes were reviewed as well as some of the processes proposed in the literature. No one outstanding process stood out, but many processes have advantages that can be employed when processing some certain ore or secondary material. The modern process technology employing ion exchange and molecular recognition appears to be more flexible considering the raw material. This has been one of the reasons besides faster and more efficient operation, why the traditional processing methods have been replaced by the modern refining processes.Item Lectures in English as a Lingua Franca - Interactional Features(Aalto University, 2012) Suviniitty, Jaana; Puunjalostustekniikan laitos; Department of Forest Products Technology; Kemian tekniikan korkeakoulu; School of Chemical TechnologyInternationalization is one of the strategic goals of universities and other higher education institutions in Finland. This tends to be transferred to English-medium instruction (EMI) and English degree programs. This "Anglicization” has raised concerns and discussion despite its perceived benefits. The aim of this study was to investigate an international Master’s Program in the field of engineering and to explore students’ perceptions of lectures and their comprehension within this Master’s Program. These lectures were further examined in order to shed light on what linguistic features used in English as a lingua franca (ELF) lecturing influence students’ perceptions. This exploratory, descriptive case study takes a phasal approach to obtain a holistic view on this Master’s Program. The findings of the study are based on authentic data: video-recorded lecture material, their transcriptions, and surveys. These surveys contain lecture evaluations provided by the students immediately after attending them. Guided by the student evaluations, an analysis based on genre analysis and discourse analysis was conducted to locate the linguistic differences of these lectures. The results indicate that students’ perception of lectures relates to the use of interactionalfeatures regardless of the lecturers’ perceived English skills. Those lectures students found accessible contained more interactional features than those lectures students found challenging. Additional results, contrary to prior studies, also show that the use of interactional features in native language (Finnish) lecturing is notably lower than in ELF lecturing. Furthermore, the comparison of student achievements when lecturing in the Master’s Program was in Finnish with the student achievements from the ELF lectured program showed slightly higher results in the ELF lectured program. Conclusions drawn from these results suggest that when lecturing in a non-native language, lecturers attempt to ensure the audience’s comprehension through various linguistic devices, interactional features being one of them. Therefore, ELF lectures do not have an adverse effect on lecture comprehension or course results.
