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The master´s thesis concentrates on a project of condensing steam turbine for existing heating plant with back pressure turbine. The master´s thesis subject consists in the thermodynamic calculation of regulating stage and turbine stages. Design documentation is worked up according to the calculated record. From calculated power of turbine is worked a basic project of gearbox and disposal arrangement system.

Mondi Dynäs is a pulp and paper producer in the north of Sweden close to the town Kramfors. Last year Mondi Dynäs produced 231,404 tons of Kraft paper. In order to increase their production to 300,000 tons of paper per year this study was done in order to investigate how the increased biomass flow would affect the generation of steam along with the steam and condensate balance. This study started with a mapping of the current steam and condensate balance for one winter period January – Mars and one summer period July – September 2015. The resulting balance is used as reference period for the development of the future steam and condensate scenario where Mondi Dynäs will achieve the targeted production of 300,000 tons of paper per year. The future model shows that the future production of paper will give an abundance of biomass since the generation of steam will be more than sufficient. For the winter period the venting of steam over roof could be derived to 11.9 tons per hour and 34.4 tons per hour during the summer period. This can be compared to the current situation where the winter period gave an average steam blow out of 8.7 tons per hour and for the summer period 13.1 tons per hour. To utilize the accumulated energy from these energy streams, three different scenarios was studied. The first scenario were a future installation of a backpressure turbine along with a condensing turbine section. The new turbine would be attached to the highest pressure level at 65.5 bar and have a backpressure exhaust at 20 bar which will give a power of 7.6 MWe. The second scenario included the implementation of a new condensing turbine with the current system design for the steam network and boilers. This turbine would be attached to the 3.5 bar network and give the electricity power of 1.9 MWe. The third scenario included the installation of a new bark dryer. This would give Mondi Dynäs the possibility to sell bark to an external actor on the energy market. From derived figures in the future scenario model it would be possible to sell 108,144 MWh of bark while running the bark boiler. Mondi Dynäs AB is recommended to add a new condensing turbine to their steam network. The new turbine would be able to produce 1.9 MWe and need a cooling water flow of 190 tons of water per hour. Derived figures for the investment shows a NPV of 0.6 MEUR and the IRR value of 31 %

Den stora användningen av fossil energi i världen är en av orsakerna till de höga utsläppen av koldioxid som förstärker växthuseffekten. För att minska människans klimatpåverkan bör därför mer förnyelsebar energi användas. EU har därför som mål att minska utsläppen av koldioxid med 40 % till år 2030. Industrisektorn står för 32 % av världens totala energianvändning och pappers- och massaindustrin använder 6 % av den energin. I denna studie undersöks Stora Enso Skoghalls Bruk som är ett pappers- och massabruk beläget norr om Vänern. De senaste åren har en rad energieffektiviserande åtgärder utförts där som gjort att det tidvis produceras ett överskott av ånga. I dagsläget friblåses överskottsångan för att hålla trycket på deras ångnät på avsedd nivå. Studiens syfte är att undersöka om elproduktion med hjälp av en kondensturbin är ett lönsamt alternativ för att ta till vara på överskottsångan istället för att friblåsa den. Målet är att ta fram ett beslutsunderlag för dimensionering och bedömning av lönsamhet samt miljöpåverkan för en kondensturbin på Skoghalls Bruk. Studien utfördes genom energitekniska beräkningar i Simulink och en lönsamhetsbedömning genom en nuvärdesanalys. Som grund till beräkningarna ligger driftdata och vetenskaplig litteratur. Scenarier har konstruerats för att avgöra hur både elpriser och koldioxidalstring knuten till den nordiska elmarknaden kan se ut i framtiden. Den samlade bedömningen av studien är att Skoghalls Bruk inte bör investera i en kondensturbin i dagsläget. Låga elpriser i kombination med höga bränslepriser gör att vinsten inte blir tillräckligt hög i förhållande till investeringskostnaden. Vid mer gynnsamma förhållanden, alltså med högre elpriser, lägre bränslekostnader och låg ränta är det mer troligt att investeringen blir lönsam. Investeringen är dock lönsam ur ett miljöperspektiv så länge kondensturbinens elproduktion ersätter någon form av fossil elproduktion i Norden. / The high use of fossil energy in the world is one of the causes of the high emissions of carbon dioxide, which increases the greenhouse effect. In order to reduce the anthropogenic climate impact, more renewable energy should be used. The EU aims to reduce carbon dioxide emissions by 40 % by the year 2030. The industrial sector accounts for 32 % of the total world energy consumption of which the pulp and paper industry uses 6 %. This study examines Stora Enso Skoghall Mill which is a pulp and paper mill located north of Vänern. In recent years, a series of energy efficiency measures has been carried out at Skoghall Mill. At times these measures have resulted in a surplus of steam production. Today this excess steam is released to the atmosphere to maintain the pressure on the steam network at the required level. The purpose of this study is to investigate whether electricity production using a condensing turbine is a profitable alternative for recovery of the excess steam which is currently being released to the atmosphere. The aim is to develop a decision basis for the design and assessment of profitability and environmental impact of a condensing turbine at Skoghall Mill. The study was conducted through energy calculations in Simulink and a profitability assessment by a present value analysis. The basis for the calculations is operational data provided by Skoghall Mill and scientific literature. Scenarios have been designed to determine both how electricity prices and generation of carbon dioxide linked to the Nordic electricity market might look in the future. The overall conclusion of the study is that Skoghall Mill should not invest in a condensing turbine at this time. The profit is not high enough compared to the investment cost due to low electricity prices combined with high fuel costs. In more favourable conditions, i.e. with higher electricity prices, lower fuel costs and lower interest rates, it is more likely that the investment will be profitable. The investment, however, is profitable from an environmental perspective, as long as the electricity from the condensing turbine is replacing fossil power generation in the Nordic region.

The content of this thesis is the design of a condensing steam turbine with an output of 80 MWe to a waste incinerator with impulse blading. In this work are elaborated proposals and calculations of balancing schemes, which are used in the next part of the work as a foundation for calculation of the blades part of the turbine. The blades part is designed for two operations - for full condensing operation and for full demand operation. The turbine should contain one process offtake and three unregulated offtakes. Besides that, the thesis solves basic strength control. The thesis is finished with a technical drawing of the longitudinal cut of the turbine.

The diploma thesis deals in the theoretical part with various types of sys-tems for the preparation of hot water and specifies the types of solar sys-tems. In the calculation part, it solves the design of kindergarten heating by a system of heating elements. It also solves two variants of hot water preparation in the hot water tank. The design also includes all the equip-ment needed for the proper functioning of the heating system. The exper-imental part compares flat panel and evacuated tube solar collectors.

Tuberculosis emerged from its grave to be one of the deadliest diseases of the present time after recently developing a synergy with AIDS. A fatty acid condensing enzyme-mtFabH has been proposed to connect the key processes involved in biosynthesis of mycolic acids, an important component of mycobacterial cell wall. It condenses long acyl Coenzymes A (CoA; up to C20CoA) with malonyl Acyl Carrier Protein (ACP) to form the elongated β-ketoacyl-ACP which further undergoes rounds of elongation to form mero-mycolate branch of mature mycolic acids. Owing to its proposed central position in mycolic acid synthesis, mtFabH has attracted considerable attention as a good anti-mycobacterial target.In this study, we utilized important biochemical tools such as site directed mutagenesis, mass spectrometry and X-ray crystallography to address some of the key unanswered questions regarding the intricate workings of mtFabH. We solved the first co-crystal structure of substrate C12CoA with mtFabH and further analyzed the substrate specificity of this acylation step. This structure depicts the mode of acyl-CoA binding in mtFabH channels; and its comparison with the parallel E.Coli-acetyl CoA structure provides important similarities and differences in substrate binding in these two FabH enzymes. It also posed an important question about the trajectory of long acyl chain CoA into the deep and "seemingly closed" substrate binding pocket of mtFabH. By utilizing disulfide-based inhibitors, we showed that large conformational changes are necessary to facilitate ligand trafficking in mtFabH while the high catalytic turnover rate of the enzyme is maintained. We also proposed the most likely location of the involved loop.A much faster and less cumbersome assay for mtFabH was also developed and it was utilized to characterize a series of inhibitors. This assay utilizes the commercially available radioactive malonyl-CoA in lieu of malonyl-ACP, the physiological substrate, and thus can serve as ACP independent assay for mtFabH.These studies further our understanding of the biochemistry of mtFabH, which along with the faster assay could be helpful in designing potent mtFabH inhibitors as anti-tubercular agents in the future.

The biosynthesis of wax components containing secondary functional groups was investigated in the current study. Two fundamentally different pathways were proposed to introduce the secondary functional groups. One pathway involves hydroxylation of elongated substrates. Wax components characterized by two functional groups located on or near the centre of the carbon chain, nonacosane-14,15-diol, -14,16-diol and -13,15-diol as well as corresponding ketols were identified for the first time in Arabidopsis stem wax. The alkanediols and ketols were dominated by the C-14,15 isomers. The absence of alkanediols and ketols in Arabidopsis mah1 mutants that are deficient in secondary alcohol biosynthesis confirmed the biosynthetic relationship between secondary alcohols and alkanediols/ketols (Chapter 3). In pea (Pisum sativum) leaf wax, two novel compound classes were identified as primary/secondary alcohols dominated by octacosane-1,14-diol and secondary/secondary alkanediols hentriacontane-9,16-diol, -8,15-diol and -10,17-diol. Co-localization of the secondary/secondary alkanediols and hentriacontan-15-ol and -16-ol pointed to a biosynthetic relationship (Chapter 4). The diverse structures of compounds identified in the current study suggested that hydroxylases can use substrates other than alkanes. The predominance of isomers within homologues indicated a regiospecificity of the hydroxylases involved in wax biosynthesis. In addition to hydroxylation, secondary functional groups could also be introduced through elongation of carbon chains. Homologous series of 5-hydroxyaldehydes (C₂₄ and C₂₆-C₃₆) and 1,5-alkanediols (C₂₈-C₃₈) were identified in yew (Taxus baccata) needle wax. The relative position of both functional groups suggested that these two compound classes are biosynthetically related and their secondary functional groups are introduced during elongation (Chapter 5). The results of incubation of ¹⁴C-labeled malonyl-CoA and acyl-CoAs with different chain lengths in the presence of California poppy (Eschscholzia californica) microsomes provided the first evidence to support the elongation hypothesis. The results indicated that a carbonyl group rather than a hydroxyl group is introduced during elongation. To provide molecular tools for further investigations of the hypothetical pathway, three full length cDNAs encoding putative KCSs were cloned and one of them, PKCSI, was functionally characterized.

The learning process consists of different steps: building a Training Set (TS), training the system, testing its behaviour and finally classifying unknown objects. When using a distance based rule as a classifier, i.e. 1-Nearest Neighbour (1-NN), the first step (building a training set) includes editing and condensing data. The main reason for that is that the rules based on distance need many time to classify each unlabelled sample, x, as each distance from x to each point in the training set should be calculated. So, the more reduced the training set, the shorter the time needed for each new classification process. This thesis is mainly focused on building a training set from some already given data, and specially on condensing it; however different classification techniques are also compared.The aim of any condensing technique is to obtain a reduced training set in order to spend as few time as possible in classification. All that without a significant loss in classification accuracy. Somenew approaches to training set size reduction based on prototypes are presented. These schemes basically consist of defining a small number of prototypes that represent all the original instances. That includes those approaches that select among the already existing examples (selective condensing algorithms), and those which generate new representatives (adaptive condensing algorithms).Those new reduction techniques are experimentally compared to some traditional ones, for data represented in feature spaces. In order to test them, the classical 1-NN rule is here applied. However, other classifiers (fast classifiers) have been considered here, as linear and quadratic ones constructed in dissimilarity spaces based on prototypes, in order to realize how editing and condensing concepts work for this different family of classifiers.Although the goal of the algorithms proposed in this thesis is to obtain a strongly reduced set of representatives, the performance is empirically evaluated over eleven real data sets by comparing not only the reduction rate but also the classification accuracy with those of other condensing techniques. Therefore, the ultimate aim is not only to find a strongly reduced set, but also a balanced one.Several ways to solve the same problem could be found. So, in the case of using a rule based on distance as a classifier, not only the option of reducing the training set can be afford. A different family of approaches consists of applying several searching methods. Therefore, results obtained by the use of the algorithms here presented are compared in terms of classification accuracy and time, to several efficient search techniques.Finally, the main contributions of this PhD report could be briefly summarised in four principal points. Firstly, two selective algorithms based on the idea of surrounding neighbourhood. They obtain better results than other algorithms presented here, as well as better than other traditional schemes. Secondly, a generative approach based on mixtures of Gaussians. It presents better results in classification accuracy and size reduction than traditional adaptive algorithms, and similar to those of the LVQ. Thirdly, it is shown that classification rules other than the 1-NN can be used, even leading to better results. And finally, it is deduced from the experiments carried on, that with some databases (as the ones used here) the approaches here presented execute the classification processes in less time that the efficient search techniques.

The biosynthesis of wax components containing secondary functional groups was investigated in the current study. Two fundamentally different pathways were proposed to introduce the secondary functional groups. One pathway involves hydroxylation of elongated substrates. Wax components characterized by two functional groups located on or near the centre of the carbon chain, nonacosane-14,15-diol, -14,16-diol and -13,15-diol as well as corresponding ketols were identified for the first time in Arabidopsis stem wax. The alkanediols and ketols were dominated by the C-14,15 isomers. The absence of alkanediols and ketols in Arabidopsis mah1 mutants that are deficient in secondary alcohol biosynthesis confirmed the biosynthetic relationship between secondary alcohols and alkanediols/ketols (Chapter 3). In pea (Pisum sativum) leaf wax, two novel compound classes were identified as primary/secondary alcohols dominated by octacosane-1,14-diol and secondary/secondary alkanediols hentriacontane-9,16-diol, -8,15-diol and -10,17-diol. Co-localization of the secondary/secondary alkanediols and hentriacontan-15-ol and -16-ol pointed to a biosynthetic relationship (Chapter 4). The diverse structures of compounds identified in the current study suggested that hydroxylases can use substrates other than alkanes. The predominance of isomers within homologues indicated a regiospecificity of the hydroxylases involved in wax biosynthesis. In addition to hydroxylation, secondary functional groups could also be introduced through elongation of carbon chains. Homologous series of 5-hydroxyaldehydes (C₂₄ and C₂₆-C₃₆) and 1,5-alkanediols (C₂₈-C₃₈) were identified in yew (Taxus baccata) needle wax. The relative position of both functional groups suggested that these two compound classes are biosynthetically related and their secondary functional groups are introduced during elongation (Chapter 5). The results of incubation of ¹⁴C-labeled malonyl-CoA and acyl-CoAs with different chain lengths in the presence of California poppy (Eschscholzia californica) microsomes provided the first evidence to support the elongation hypothesis. The results indicated that a carbonyl group rather than a hydroxyl group is introduced during elongation. To provide molecular tools for further investigations of the hypothetical pathway, three full length cDNAs encoding putative KCSs were cloned and one of them, PKCSI, was functionally characterized.