Examensarbeten på grundnivå // Basic Level Theses
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- PostLarge, viscosity-enhancing polyelectrolyte complexes and an assessment of their contribution to dry strength in paper(2010) Holmgren, Karin; Chalmers tekniska högskola / Institutionen för kemi- och bioteknik; Chalmers University of Technology / Department of Chemical and Biological Engineering
- PostAvvattning av biologiskt slam(2011) Nes, Ganic; Chalmers tekniska högskola / Institutionen för kemi- och bioteknik; Chalmers University of Technology / Department of Chemical and Biological Engineering
- PostThe influence of the nitrate load on the denitrification capacity(2011) Eriksson, Jenny; Chalmers tekniska högskola / Institutionen för kemi- och bioteknik; Chalmers University of Technology / Department of Chemical and Biological EngineeringGryaab AB, which runs the Rya plant in Gothenburg has expanded its wastewater treatment plant with a new nitrogen and phosphorus removal facility, this in order to achieve the new target values concerning emissions of nitrogen and phosphorus. The new conditions is 0.3 mg/l phosphorus and 10 mg/l nitrogen in the effluent per calendar year. The new nitrogen removal is a post-denitrification plant where bacterias are growing in suspended carriers, so called MBBR-technology. Since this type of biological treatment technology is relatively new there is not so much knowledge about how to operate it to obtain the most effective capacity. The post-denitrification plant at the Rya has six denitrification lines, each line consists of three reactor zones. First zone is designed to be used both as a nitrification- and denitrifikation zone. The thesis aims to study how different nitrate load affects the denitrification capacity. The method for studying the capacity is based on having a test line with low nitrate (NO3) load, 85 NO3 kg / day and a reference line with a high nitrate load, 288 NO3 kg / day. A flow control is used to give a constant nitrate load to the line by regulating the flow of the incoming nitrate concentration.. Denitrification tests are performed to study the changes in the capacity when the nitrate load is altered. The tests are designed to to simulate the condition in the full-scale plant, i.e. oxygen free environment and the carriers under constant suspension. The tests shows the denitrification rate of the bacteria in the postdenitrification plant, and thus the denitrification capacity. During 10 weeks the denitrification in the post-denitrification plant were studied. The first experimental period the test-line had low nitrate load, followed by a period in which the test-line had high nitrate load, and finally a period in which the nitrate load was again low. The reference line had during the study high nitrate load, 288 NO3 kg/day. The results show that at low nitrate load the capacity diminishes for 13-14 days and then stabilizes. Repeatability at low nitrate load exists and with a nitrate load of 85 kg NO3 / day the capacity stabilizes at approximately 1,1- 1,3 gN/m2/d. In the study with high nitrate load, 288 NO3 kg/day the capacity has already increased after 9 days from about 1,1 to 1,8 gN/m2/d gN/m2/d. The highest denitrification capacity value observed was 2,2 gN/m2/d.
- PostThe oxidation behavior of Fe-2.25Cr-1Mo in presence of low amounts of ZnCl2 at 300-400°C(2011) Ålander, Gustaf; Åkesson, Patrik; Chalmers tekniska högskola / Institutionen för kemi- och bioteknik; Chalmers University of Technology / Department of Chemical and Biological EngineeringTo reduce emissions of carbon dioxide, alternative sources for energy production have been adopted in high extent, e.g. biomass. However, since biomass contains higher concentrations of alkali metals and heavy metals compared to fossil fuels [1], corrosion problems e.g. on the waterwalls in biomass fired boilers occur in larger extent. In this work, the corrosion behavior of the low alloyed steel Fe-2.25Cr-1Mo, used in waterwalls due to its economical advantage and mechanical properties, in presence of low amounts of ZnCl2 at 300 – 400°C is investigated. Laboratory experiments were carried out in a tube furnace in wet atmosphere containing 5% O2, 40% H2O in N2, with exposure times up to 168 h. Prior exposures, sample coupons were cleaned, polished, dried and deposited with 0.1 mg ZnCl2/cm2. After exposure, the coupons were analyzed with scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) and X-ray diffraction (XRD). In absence of ZnCl2 at 300°C, only a very small mass gain was measured by gravimetry. In the presence of ZnCl2, a local corrosion attack concentrated to the deposits was observed matching the composition of ZnO, the spinel Fe2ZnO4 and iron oxides. 1 and 24 h exposure yield a mass loss, partly explained by evaporation of solvent and chlorine. After 168 h, a mass gain was observed. In absence and presence of ZnCl2 at 400°C, the mass gain was considerably higher than at 300°C. In presence, no mass loss was observed, indicating faster oxidation rate.
- PostUtveckling av virtuella världen "Krimlab" - Spelbaserat lärande för tonåringar(2011) Andersson, Viktoria; Chalmers tekniska högskola / Institutionen för kemi- och bioteknik; Chalmers University of Technology / Department of Chemical and Biological Engineering
- PostOrganisk beläggning av jonbytarkorn. Optimerat vattenavsaltningsförfarande på ett kärnkraftverk(2011) Grassl, Susan; Chalmers tekniska högskola / Institutionen för kemi- och bioteknik; Chalmers University of Technology / Department of Chemical and Biological Engineering
- PostDevelopment of two methods to evaluate lubricating greases using a rheometer(2011) Agernäs, Oskar; Tenberg, Tommy; Chalmers tekniska högskola / Institutionen för kemi- och bioteknik; Chalmers University of Technology / Department of Chemical and Biological EngineeringLubricating greases are crucial for both industry and every day applications. Lubrication has become a natural part of all moving equipment and lubricating grease plays an important role in keeping different machinery running without failure. Even if it is widely known that grease is vital for many devices, deep and specific knowledge of how grease behave in terms of rheological stresses is scarcely found. The scope of this project was to investigate and develop a standard method of conducting rheological measurements on lubricating greases. Two analytical methods to evaluate apparent viscosity and flow point were developed and evaluated. It was found that different greases did have measurable differences and that the methods evaluated could assist in comparing different greases to each other as well as in selecting the best grease for specific equipment. At higher temperatures a local minimum for both apparent viscosity and flow point was found. The root of this minimum is probably found in the thickener system of lubricating grease. The development of a new standard method for measurements of lubricating greases requires further investigation of why grease behave the way it does under rheological stress.
- PostMethod for measurement of core integrity for baby diapers(2011) Eklund, Emilie; Chalmers tekniska högskola / Institutionen för kemi- och bioteknik; Chalmers University of Technology / Department of Chemical and Biological Engineering
- PostMethod development for determining antimicrobial effect of silver-containing materials and dressings with varying level of moisture saturation(2012) Åkerman, Julia; Chalmers tekniska högskola / Institutionen för kemi- och bioteknik; Chalmers University of Technology / Department of Chemical and Biological Engineering
- PostStudy of the phosphorous separation in the AKD plant Eka Chemicals in Trollhättan(2012) Abdallah, Zeinab; Chalmers tekniska högskola / Institutionen för kemi- och bioteknik; Chalmers University of Technology / Department of Chemical and Biological Engineering
- PostTailor-made silver particles by microemulsion for use in catalysts(2012) Almqvist, Frida; Kempe, Catherine; Chalmers tekniska högskola / Institutionen för kemi- och bioteknik; Chalmers University of Technology / Department of Chemical and Biological Engineering
- PostHögtemperaturoxidation av FeCrAl legeringar vid låg syreaktivitet(2012) Fager, Cecilia; Hansson, Bonnie; Chalmers tekniska högskola / Institutionen för kemi- och bioteknik; Chalmers University of Technology / Department of Chemical and Biological Engineering
- PostCharacterization of Acetylcholine esterase - gold nanoparticle conjugates(2012) Åkesson, Sebastian; Chalmers tekniska högskola / Institutionen för kemi- och bioteknik; Chalmers University of Technology / Department of Chemical and Biological Engineering
- PostTillverkning, karaktärisering och utvärdering av en ny klass av joniska lösningsmedel(2012) Lekström, Glen; Chalmers tekniska högskola / Institutionen för kemi- och bioteknik; Chalmers University of Technology / Department of Chemical and Biological Engineering
- PostEvaluation of chocolate microstructure(2012) Nilsson, Jesper; Chalmers tekniska högskola / Institutionen för kemi- och bioteknik; Chalmers University of Technology / Department of Chemical and Biological Engineering
- PostFumigation av fraktcontainrar(2012) Lysberg, Emelie; Chalmers tekniska högskola / Institutionen för kemi- och bioteknik; Chalmers University of Technology / Department of Chemical and Biological Engineering
- PostImpact of sourdough on in vitro starch hydrolysis in wheat tortilla bread(2012) Hidebring, Elin; Chalmers tekniska högskola / Institutionen för kemi- och bioteknik; Chalmers University of Technology / Department of Chemical and Biological Engineering
- PostCharacterisation of chemical decomposition of biodiesel with a focus on B10, B30 and B100 blends.(2012) Wäring, Jens; Svanberg, Krister; Chalmers tekniska högskola / Institutionen för kemi- och bioteknik; Chalmers University of Technology / Department of Chemical and Biological Engineering
- PostExamination of the factors determining the degree of gloss in paint films(2012) Farmand, Eliza; Chalmers tekniska högskola / Institutionen för kemi- och bioteknik; Chalmers University of Technology / Department of Chemical and Biological Engineering
- PostAnalysis of acrylic acid, phosphoric acid and 2-ethylhexylamine in surfactant with capillary electrophoresis(2012) Larsson, Napaporn; Chalmers tekniska högskola / Institutionen för kemi- och bioteknik; Chalmers University of Technology / Department of Chemical and Biological Engineering