The presence of pharmaceuticals in the environment has raised an emerging interest due to the fact that they pose negative environmental impact and health hazards related to long-term toxicity effects. As conventional treatments are not able to totally remove these substances it is necessary to seek for alternative advanced technologies such as oxidation with chlorine dioxide (ClO2). The objective of this master thesis is thus to find the most optimal dose – reaction time of ClO2 for the oxidation and maximum removal of selected environmentally relevant pharmaceuticals. Factorial design and subsequent optimization with MODDE was selected as the best approach to find the optimal dose – time. Batch oxidation tests were conducted on 100mL aliquots treated with ClO2 using wastewater effluent from Henriksdal WWTP. Thereafter solid phase extraction and final determination of pharmaceuticals was carried out on a high performance liquid chromatography- triple quadrupole mass spectrometry (HPLC-MS/MS). Results showed that applying a dose of 5 mg ClO2/L and a reaction time of 10 minutes, it is possible to remove more than a half of the 17 analyzed substances. Besides most of the pharmaceuticals with high and moderate environmental risk, would pose a low risk for the environment after treatment with the optimal ClO2 dose – reaction time. Despite the fact that ClO2 could successfully degrade most environmentally relevant pharmaceuticals, deeper research concerning the formation of toxic by-products after oxidative treatment needs to be done before upscaling this technology to pilot or full scale as a suitable end of pipe technology for pharmaceuticals removal.

The process optimization of continuous annealing furnace, RHF 125, for recrystallization annealing of two steel grades, Sandvik 13C26 and Sandvik 20C has been carried out. To recreate the continuous annealing process carried out in the roller hearth furnace in the industry, samples with different cold reduction rates were chosen from ongoing production lines. An experimental heat treatment model was chosen by the ‘Design of Experiments’ approach from MODDE (from U-Metrics). The annealing temperature was chosen below the austenitization temperature for both steel grades and soaking time of 30 seconds to 240 seconds were chosen. Microscopic estimation of fraction recrystallized was performed with the help of Electron Back Scattered Diffraction, accompanied by mechanical testing methods to measure the hardness and yield strength of the steel strips. The experimental output was used to create a model to correlate between the different cold reduction rates and annealing parameters to achieve a higher degree of recrystallization along with desirable mechanical properties. Also, a modified Johnson-Mehl-Avrami-Kolomogrov model, based on hardness values, to determine the transformation kinetics by tracking the progress of recrystallization was developed. The model was verified with EBSD measurements for Sandvik 13C26 strip steels. For 20C, inhomogeneous recrystallization was observed, thus limiting the model’s adaptability to steels which exhibit homogeneous recrystallization behavior and negligible change in precipitation and/or coarsening of secondary phases. / Processoptimering av en kontinuerlig glödgningsugn, RHF 125, för rekristallisationsglödgning av två Sandvik-stål, Sandvik 13C26 och Sandvik 20C, har genomförts. För att återskapa den kontinuerliga glödgningsprocessen som utförs den verkilga processen i valdes prover och olika kallreduktionshastigheter från pågående produktionslinjer. En experimentell värmebehandlingsmodell valdes med metoden 'Design of Experiments' med MODDE (från U-Metrics). Glödgningstemperaturen valdes till en temperatur under austeniseringstemperaturen för båda stålen och hålltider varierade från 30 s till 240 s. Mikroskopisk uppskattning av fraktionen rekristalliserat material utfördes med hjälp av Electron Back Scatter Diffraktion (EBSD), åtföljd av mekaniska testmetoder för att mäta hårdheten och sträckgränsen för stålproverna. De experimentella resultaten användes för att skapa en modell för att korrelera mellan de olika reduktionshastigheterna och glödgningsparametrarna för att uppnå högre grad av rekristallisation tillsammans med önskvärda mekaniska egenskaper. Dessutom utvecklades en modifierad Johnson-Mehl-Avrami-Kolomogrov-modell, baserad på hårdhetsvärden, för att bestämma transformationskinetiken genom att spåra evolutionen för rekristallisation. Modellen verifierades genom jämförelse med EBSD-mätningarna för Sandvik 13C26 bandstål. För 20 °C observerades inhomogen rekristallisation, vilket begränsade modellens användbarhet till stål som uppvisade homogent rekristallisationsbeteende och försumbar förändring i utskiljning och/eller förgrovning av sekundära faser.