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Intresset för användningen av material från förnybara råvaror ökar. Produktionen av vedmassa och material i skogsindustrin genererar dagligen stora mängder biprodukter, särskilt bark. Barken innehåller många värdefulla komponenter som kan förädlas och öka värdet för barken, men först måste de separeras. Målet med denna undersökning var att separera dessa genom att jämföra två olika typer av extraktionsmetoder. Den första metoden använde programmerbar utrustning som namnges accelerated solvent extraction (ASE) och den andra använde manuell teknik som namnges Soxhlet extraktion. Syftet med undersökningen var att avgöra vilken extraktionsmetod som kan användas till att utvinna bark komponenter mest effektivt. Metoden ASE omfattar acetonextraktion och varmvattenextraktion där trycket var 100 bar, temperaturen 100oC och tiden drygt en timme. Soxhletextraktion omfattade enbart acetonextraktion under atmosfäriskt tryck, kontinuerlig värme och tiden 90 minuter. ASE-metoden gav fyra extrakt; acetonextrakt vid 100oC samt varmvattenextrakt vid 100oC, 140oC och 160oC.  Barken som studerades var uppdelad i två fraktioner, fuktig bark och torr bark. En beräkning av utbyte % utfördes efter varje extraktion. Extrakten från fuktig bark hade mörkare färg än extrakten från torr bark. Det uppmätes pH-värden för alla vattenextrakt och den som gav lägst pH var vattenextrakt som erhölls vid 160oC. Slutligen visade utbyteresultaten inga stora skillnader mellan de utförda ASE vattenextraktionerna exklusive extraktfärgen som kan vara en indikation till skillnad i extraherade molekyler. Användningen av sand under varmvattenextraktionerna gav inga förbättringar i extraktionsmetoden. / Interest in the use of materials from renewable sources is increasing. The production of wood pulp and materials in the forest industry generates large amounts of by- products daily, especially tree bark. Bark contains many valuable components which if separated can be used in various types of applications. The aim of this study was to compare two extraction methods. The first method used programmable equipment and is named accelerated solvent extraction (ASE) and the second used manual technology and is named Soxhlet extraction.  The purpose of the study was to determine which extraction method can be used to extract bark components more efficiently. The ASE method included acetone extraction and hot water extraction where the pressure was 100 bar, the temperature 100oC and the time just over an hour. Soxhlet extraction involved only acetone extraction under atmospheric pressure, continuous heating, and a time of 90 minutes. The ASE method yielded four extracts: acetone extract at 100oC and hot water extract at 100oC, 140oC and 160oC.  The bark studied was divided into two parts, undried bark and dry bark. Total calculation of yield% was performed after each extraction. The extracts from undried bark had a darker color than the extracts from dry bark. The pH values were measured for all water extracts and the one that gave the lowest pH was obtained at 160oC. Finally, the extraction results did not show any major differences between the ASE water extractions performed excluding the extract color which may be an indication of difference in extracted molecules. The use of sand during the hot water extractions did not improve the extraction method.

<p>Flow accelerated corrosion(FAC) results in wall thinning of pipes, tubes or vessels from exposure to flow due to corrosion. If FAC is not detected, it can lead to sudden failure of piping components. Orifices are used in piping systems to monitor and control the flow. Flow separation and reattachment downstream of an orifice can enhance the mass transfer of the pipe wall. In this thesis, the effect of Reynolds numbers and surface roughness on the mass transfer rate downstream of an orifice was investigated. A dissolving wall method was used to measure the wall mass transfer. The test sections were cast from gypsum with water as the working fluid. Multiple destructive tests were performed for different test times in a 2.5 cm diameter flow loop, and the wear topology measured by a laser scanner to obtain the progression of wear with time over the pipe surface. None-destructive tests were performed in a 20 cm diameter flow loop using test section with an inner gypsum lining, and measured online at selected locations using an ultrasonic method. Experiments were performed at Reynolds numbers of 80000, 140000 and 200000 in the 2.5 cm diameter flow loop, and at 180,000 in the 20 cm diameter flow loop with an orifice to pipe diameter ratio of 0.5. The results show that different surface roughness patterns are developed at different Reynolds numbers from the initially smooth surfaces. The different surface roughness patterns have a significantly different effect on the mass transfer rate downstream of an orifice. A larger population of scallops developed from the smooth pipe surface, as the Reynolds number was increased, which enhanced the mass transfer rate. The mass transfer rate in the 20 cm diameter test section was much smaller than in the 2.5 cm diameter test section at a similar Reynolds number. The pattern of the roughness in the 20 cm diameter test section was formed as isolated roughness which is similar to the roughness pattern in 2.5 cm diameter test section at much lower Reynolds number.</p> / Master of Applied Science (MASc)

京都大学 / 新制・課程博士 / 博士(工学) / 甲第23483号 / 工博第4895号 / 新制||工||1765(附属図書館) / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 杉浦 邦征, 教授 清野 純史, 教授 八木 知己 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM