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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
231

Développement d'un procédé de production de biodiesel de troisième génération à partir d'un déchet organique issu de l'agro-industrie réunionnaise : la vinasse de distillerie / Biotechnological valuation for distillery slops as biodiesel

Hoarau, Julien 20 September 2016 (has links)
La Réunion dispose d'un gisement important de ressources organiques renouvelables dont une grande partie est sous forme de déchets liquides tels que les vinasses de distillerie, représentant plus de 150 000 tonnes d'effluent par an. Les problématiques de gestion de ces effluents sont fortement impactées par leur haute charge en élément organique et nécessitent la mise en œuvre de techniques de dépollution coûteuses. Leur valorisation en tant que matière première est donc une voie potentielle pour une gestion plus efficace et économiquement rentable. Parmi les nombreuses pistes de valorisation biotechnologiques existantes pour les vinasses de distillerie, nous nous sommes proposés dans ce projet de valoriser ces déchets sous forme de biodiesel. La sélection de microorganismes oléagineux (champignons filamenteux et levures) adaptés aux déchets liquides de distilleries locales en vue de leur transformation en biodiesel a mis en avant les capacités de croissance des souches de champignons filamenteux dont 60% de celles testées ont démontré une croissance supérieure à 8 g/L et allant jusqu’à 20 g/L, avec des capacités de mobilisation des ressources nutritives de la vinasse jusqu’à 50% de l'azote et du carbone organique. L'adaptation du procédé à la levure oléagineuse Yarrowia lipolytica, connue comme microorganisme oléagineux modèle pour la production de biodiesel a mis en évidence une carence en phosphate limitante pour la croissance de ce microorganisme, ainsi qu'une amélioration de 80% de la biomasse produite observée après ajout de KH2PO4. Par ailleurs, la mobilisation du matériel enzymatique d'un microorganisme à forte croissance sur vinasse a également permis d'obtenir une amélioration de la production de biomasse levurienne, laissant entrevoir la possibilité de valorisation d'un cocktail enzymatique spécifiquement adapté à la dégradation de vinasses de distilleries. Enfin, l'évaluation de protocoles de transformation des lipides plus efficaces a été réalisée en cherchant à limiter les coûts liés au séchage et à l'extraction des lipides avant méthanolyse. L'application de la transestérification directe de la biomasse a permis une production plus importante de biodiesel comprise entre 10 et 90 % selon l'humidité de la biomasse, démontrant la possibilité de supprimer l'étape d'extraction des lipides. Par ailleurs, la combinaison de catalyseurs basiques et acides permet d'augmenter les rendements en biodiesel à partir de biomasse humide pour se rapprocher des performances obtenues sur biomasse sèche. / Reunion Island offers an important source of renewable organic resources, much of which is in liquid waste such as distillery slops, representing more than 150 000 tons of effluent annually. The management issues of these effluent are strongly affected by their high load of organic element and require implementation of expensive decontamination techniques. Their value as raw material is thus a potential route for more efficient and cost-effective management. Among the many tracks of biotechnological valuation existing for distillery slops, this project focus on enhancing these wastes as biodiesel. The selection of oleaginous microorganisms (molds and yeasts) suitable for liquid waste of local distilleries for further processing into biodiesel have demonstrated the high growth ability of filamentous fungi with 60% of tested strains offering higher growth than 8 g/L and up to 20 g/L, with nutrient resource mobilization capacities from vinasse up to 50% of the nitrogen and organic carbon. Adapting the process to the oleaginous yeast Yarrowia lipolytica, known as oleaginous microorganism model for biodiesel production highlighted a phosphate deficiency limiting for the growth of this microorganism with 80% improvement observed when KH2PO4 was fed. Furthermore, the mobilization of the enzymatic equipment of a high growing microorganism on vinasse has also yielded improved biomass production, raising the possibility of recovery of an enzymatic cocktail specifically adapted to the degradation of distillery slops. Finally, the evaluation of more effective lipid transformation protocols was conducted in seeking to limit the costs for drying and lipid extraction prior to methanolysis. The application of the direct transesterification of biomass has increased production of biodiesel between 10 and 90% depending on the moisture of biomass, demonstrating the ability to remove lipid extraction step. Furthermore, the combination of basic and acidic catalysts can increase biodiesel yields from wet biomass to reach performance close to dry biomass.
232

The crustal structure of the northern Juan de Fuca plate from multichannel seismic reflection data

Hasselgren, Elizabeth January 1991 (has links)
The crustal structure of a young (<10 My) ocean basin is imaged by two multichannel seismic reflection lines comprising 230 km recorded over the central part of the northern Juan de Fuca plate off western Canada. The more northerly line ties previously interpreted deep seismic reflection lines across the Juan de Fuca ridge and the Cascadia subduction zone; the southern line ties with another interpreted line across the subduction zone. Both lines trend obliquely to the spreading direction. A marine refraction profile crossing the eastern end of the lines provides velocity constraints. The processing sequence applied to the data includes a prestack inside-trace mute of CMP gathers to reduce noise levels on the deep data, CMP stack, post-stack dip filtering, f-k migration and bandpass. Coherency-filtered stacks are helpful in tracing weaker reflectors. The stacked sections reveal a horizontally layered sedimentary sequence overlying a rugged and prominent basement reflector dipping slightly landward. A strong, fairly continuous reflection from the base of the crust at about 2 s two-way-time below the basement surface generally mimics the basement topography and shows the characteristic doubling and tripling of reflections seen in other similar surveys. Although in general the crust appears acoustically transparent, weaker, discontinuous intracrustal reflectors are observed over 40 km at the eastern end of the northern line, and are interpreted to arise from the oceanic Layer 3A/3B and Layer 2/3 boundaries. The im-persistence of these reflectors is an indication of the complexity of the processes producing intracrustal reflectivity, and an indication of the lateral variability of crustal formation. Pseudofault traces of propagating rifts are crossed at three different locations on the two lines, the first MCS crossings of such structures. Crust associated with the pseudofault traces is related to both subhorizontal and dipping subcrustal events which are interpreted as zones of crustal thickening or underplating. Although the crustal thickness elsewhere on the lines varies by only about 10%, crust associated with the pseudofaults is as much as about 25% thicker than average, suggesting that magma supply at transform-type offsets may at times be large. A small seamount discovered on the southern line may result from the excessive magma production at the ridge postulated at propagating rift zones. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
233

A re-evaluation of the seismic structure across the active subduction zone of Western Canada

Drew, Jeffrey John January 1987 (has links)
The 1980 Vancouver Island Seismic Project (VISP) was conducted to investigate lithospheric structure associated with the underthrusting oceanic Juan de Fuca plate and the overriding continental America plate. The principal components of the survey were: (l) an onshore-offshore refraction line, which was approximately perpendicular to the continental margin (line 1), and (2) a refraction line which ran along the length of Vancouver Island approximately parallel with the continental margin (line IV). Lines I and IV were originally interpreted by Spence el a.1. (1985) and McMechan and Spence (1983), respectively. However since the original interpretations of these lines, deep multichannel seismic reflection data have been obtained on southern Vancouver Island as part of the 1984 LITHOPROBE project and off the west coast of the island during a marine survey in 1985. This study was undertaken to resolve differences between the subsurface structures proposed in the original interpretations of lines I and IV and those suggested by the more recently acquired deep reflection data. The vertical two-way traveltimes to prominent reflectors, observed in the onshore-offshore deep reflection data, were used as a constraint in constructing velocity models which are consistent with both the reflection and refraction data. The traveltimes and amplitudes observed in the VISP refraction data were modeled using a two-dimensional raytracing and asymptotic ray theory synthetic seismogram routine. The principal difference between the model originally interpreted for line I and the revised model involves the introduction of a twice repeated sequence of a low velocity zone (≈ 6.4 km/s) above a thicker high velocity zone (≈ 7.1 km/s) for the underplated region directly above the subducting Juan de Fuca plate in place of the single high velocity block underlain by a thick low velocity zone. The revised model for line IV is significantly different from the originally interpreted model. The two low-high velocity zones of line 1 are continued along the length of the island at depths between 10 and 35 km. Below this, the structure of the subducted plate is included to maintain consistency with the revised model developed for line 1. Additional features of the revised onshore-offshore model corresponding to line 1 include an oceanic lithosphere that dips approximately 3° beneath the continental slope, then 14° to 16° beneath the continental shelf and Vancouver Island, and an average velocity for the upper oceanic mantle of 8.22 km/s. Two separate two-dimensional models were needed to explain the data collected along line IV as a result of considerable azimuthal coverage due to a 30° change in profile direction. The revised models developed for line IV are consistent with the revised model developed for line 1. The velocity in the upper 10 km ranges from 5.5 km/s to approximately 6.7 km/s. Below 10 km the velocity structure is consistent with that interpreted for line 1 and shows some variations along strike of the subduction zone. Several possible interpretations can be made for the origin of the sequence of layers directly above the subducting plate beneath Vancouver Island. The two favored interpretations are: (1) a. three stage tectonic process consisting of: stage 1 — offscraping of sediment from the top of the subducting plate forms the uppermost low velocity layer in the sequence; stage 2 — an imbricated package of mafic rocks derived by continuous accretion from the top of the subducting oceanic crust forms the first high velocity layer; and stage 3 — stages 1 and 2 repeat themselves with stage 2 currently occurring; or (2) remnant, pieces of oceanic lithosphere left stranded above the current subducting plate during two previous episodes of subduction in which the subduction thrust jumped further westward isolating the remnant. The revised model along line IV indicates that this process of subduction underplating could have been a pervasive feature of this convergent margin. / Science, Faculty of / Physics and Astronomy, Department of / Graduate
234

Shallow crustal structure of the Endeavour Ridge segment, Juan de Fuca Ridge, from a detailed seismic refraction survey

Cudrak, Constance Frances January 1988 (has links)
The Endeavour Ridge is a segment of the Juan de Fuca Ridge, an active spreading centre which lies off western North America between the Pacific and Juan de Fuca plates. This segment is a bathymetric high and a site of hydrothermal activity—both characteristics suggest an underlying heat source such as an axial magma chamber which is associated with crustal generation. To investigate the creation and evolution of oceanic crust, a detailed refraction survey was carried out over the Endeavour Ridge in the fall of 1985. As a component of this survey, a diamond-shaped array consisting of eight OBS along a 20-km line across the ridge and two OBS placed along it at distances of 10 km on either side of the cross-ridge line was deployed to define the shallow crustal structure near and beneath the ridge, especially the possible existence of an axial magma chamber. Airgun shots at 0.2 km intervals along ~300 km of profiles provide conventional reversed and unreversed refraction lines as well as multiple full azimuthal coverage of the region. Travel-time and amplitude data from fifteen in-line airgun profiles recorded on the inner array were forward modelled using an algorithm based on asymptotic ray theory with a starting model obtained from a concurrent study. Two-dimensional models were constructed and then combined to obtain the three-dimensional structure of the region. These models consist of four layers, with the average model correlating well to the classic model of oceanic crust. Layer 2A averages 0.40 km in thickness and has velocities of 2.6 km/s and 2.8 km/s at the top and bottom of the layer, respectively. To achieve such a low velocity, Layer 2A must consist of highly fractured vesicular basalts. A sharp velocity increase to 4.8 km/s marks the transition to Layer 2B. This velocity discontinuity is also visible as a reflector on a. multichannel reflection line obtained through the centre of the study region and is caused by an abrupt decrease in porosity. Layer 2B averages 0.67 km in thickness, has a velocity of 5.4 km/s at its base and consists of less fractured pillow basalts and sheet flows. The Layer 2B-Layer 2C interface is a velocity increase to 5.8 km/s and is the pillow basalt-sheeted dike contact. A small velocity increase from 6.3 to 6.5 km/s delineates the base of the 0.95 km-thick Layer 2C which is the boundary between the sheeted dikes and cumulate gabbros in Layer 3. Layer 3 has the lowest velocity gradient (0.30 s⁻¹) and a velocity of 7.3 km/s at 4.65 km below the seafloor, the maximum depth constrained by the modelling. Lateral heterogeneities on the scale of 2-3 km are superimposed on this basic velocity structure. These heterogeneities are effects of porosity changes, differential pressure changes, and alteration caused by hydrothermal circulation. Layer 2A thins and increases in velocity away from the ridge; ridge-parallel cracks create a velocity anisotropy of ~10-25%, the faster direction parallel to the ridge. Velocities within Layers 2B and 2C also increase by 0.1 km/s away from the axis of the ridge. Layer 3 velocities decrease by 0.1 km/s for arrivals travelling under the ridge. Increased Layer 2 velocities at the ridge crest reveal high lateral velocity constrasts in very young crust, but within 0.03 Ma the oceanic crust at the ridge has matured to the off-ridge structure. No firm evidence exists for a large magma chamber under Endeavour Ridge. Although the bathymetric high and high-temperature hydrothermal discharges are evidence for a magma chamber, the lack of recent sheet flows at the ridge crest and the presence of a rift along the crest indicate the magma chamber is waning and must be of a size (<1 km in width) not resolvable by seismic refraction data. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
235

Water Governance in the SDG Era - An Analysis of National Commitments to Water, Sanitation, and Hygiene

Schiedek, Leonie January 2020 (has links)
The 21st century is marked by the forecast of a frightful set of crises caused by anthropogenic activities. Among them, an emerging water crisis threatens the existence of life on the planet. It is mainly triggered by a lack of good water governance. The concept of water governance refers to a range of different societal systems that are involved in the management of water resources, and the delivery of water services. However, these systems are threatened by several problems causing a mismanagement of water resources, involving corruption, deficits of democratization, or inequalities. This study examines commitments to improved water, sanitation, and hygiene provided by the Sanitation and Water for All partnership through a qualitative content analysis in order to allow an insight in current goal-setting for improved water governance. In this study, we show that even though stakeholders across geographical regions and constituencies aim at efficient governance measures, they neglect the importance of the procedural factors of good governance, for instance participation or adaptiveness. Instead they mostly focus on the outcome. Further, the study reveals that the commitments lack timely and measurable components and often do not include allocation of budgets. Although stakeholders show their intention to commit to action and work collaboratively, they often lack long-term thinking. Against the background of emerging global challenges in the water sector, most stakeholders are not yet prepared to work efficiently with new forms of governance in order to establish sustainable and resilient systems. Nevertheless, multi-stakeholder partnerships provide a basis to start a learning journey and can help to facilitate capacity development and future literacy. This thesis reveals starting points for improvement, gives practical recommendations for action and further research directions, that are necessary to explore the differences between regions and constituencies further and improve the goal-setting process in the following years.
236

Design kadeřnického křesla / Design of armchair for hairdressing

Nečasová, Barbora January 2008 (has links)
This thesis aims to design a modern innovative hairdresser chair. The main innovation of the proposal is seen in the new interior arrangement with a washing component as a central point. The main idea of the whole work is to design such a hairdresser chair that would supersede all other chairs normally used in hairdressing salons. All activities concerned with the hair care (washing, trimming, colouring etc.) would be done on a sole chair that would be in the case of need placed to the washing component. By reclining the chair backrest and turning the washing component a client’s hair could be easily washed (or other functions that need water tap could be done). There are several advantages within this proposal. Primarily it offers fewer chairs in hair dressing salon as well as a more variable interior. Another positive feature is that the washing component can be used more economically when it serves to more seats. Finally, the visual aspect and shape interconnection of two basic components - washing basin and hairdresser’s chair - are innovative.
237

Achieving safe free residual chlorination at point-of-use in emergencies: a modelling approach

Wu, Hongjian 06 May 2020 (has links)
While free (breakpoint) chlorination is widely utilized in humanitarian water treatment, a main challenge limiting its effective application is in determining the initial dose to satisfy both health requirements and aesthetic considerations (i.e. taste and odour). International guidelines and studies showed varying recommendations for the initial chlorine dose and many did not consider chlorine decay during water transportation and storage for up to 24 hours. The main objective of this thesis is to develop a tool for humanitarian staff to accurately determine the initial chlorine dose for achieving free chlorine residual (FCR) objectives with the limited instrumentation and information in the field. The first manuscript included in the thesis gathered and evaluated seven basic chlorine decay models’ applicability in humanitarian treatment contexts. All seven models were found able to accurately describe chlorine decay in water representative of humanitarian treatment contexts with more than half of the regression resulted in R2 over 0.95. However, each model had its own limitations, which were discussed. The second manuscript involved conducting extensive chlorine decay tests in water with different characteristics, explored the relationships between the estimated chlorine decay constant and several water parameters including pH, turbidity, ultraviolet absorption at 254 nm wavelength (UVA254), temperature and 30-minute chlorine demand. It was found that the UVA254 of water followed linear and exponential relationships with the decay constant in Feben and Taras’s empirical model and that in the first order model respectively. Arrhenius-type relations were verified between the decay constant and water’s temperature. A model developed to predict FCR decay in water with known 30-minute chlorine demand accurately predicted FCR level in synthetic water (with humic acid being the main constituent) but underpredicted FCR decay in water with additional chlorine consuming matter. Further research on additional chlorine decay mechanisms are needed to expand the applicability of the model. / Graduate / 2021-04-13
238

Bamboo as a Sustainable Engineering Material: Mechanical Properties, Safety Factors, and Experimental Testing

Sánchez Vivas, Lorena 03 July 2019 (has links)
With exponential global population growth occurring and associated environmentally destructive consumption of natural resources, alternative materials that are fast growing and sustainable are being sought out to satisfy human needs. One material that is fast growing and sustainable that can be used to meet most basic needs of humans (i.e. shelter, food, tools) is the plant bamboo, of the grass family Poaceae. Bamboo was used in the past by native peoples who lived in the environment where bamboo natively grows (all continents except Europe and Antarctica) with proven success for uses such as shelter, piping, tools, wells, food, fencing, baskets and much more. These practices were mostly abandoned and deemed obsolete due to the introduction of long lasting ‘modern’ building materials of steel and concrete which gained popularity in the 1800s. Now, in the current century with much advancement in science, technology, and education, humanity is reconsidering many practices and returning to more ancient practices and ways that are better for human health, the environment, and overall sustainability. These environmental considerations are drivers of this research, which focuses on how to use bamboo for engineering applications. First, in order to use a material for engineering and design applications, a material must be destructively tested to attain material property values. Therefore, a critical examination of the bamboo mechanical property values published literature was performed. It was found that although many scientists all over the world have been working on mechanical property testing of bamboo, their results have been published in different journals, in different languages, and had not yet been aggregated and compared. This led to the first study in this work that analyzed mechanical property data from 43 bamboo peer-reviewed publications written in English, Spanish, and Portuguese (the three main languages in which bamboo literature is published). This study focused on aggregating mechanical property values, establishing a range of values for each property as well as an average, and correlating the difference in property values to bamboo variables stated in bamboo literature (age, bamboo species, density, moisture content, post-harvest treatment, and testing standard employed). The five mechanical properties reviewed were: shear strength, compressive strength, tensile strength, bending strength / modulus of rupture (MOR), and modulus of elasticity (MOE) and their average values were 9 MPa, 52 MPa, 159 MPa, 120 MPa, and 16 GPa, respectively. Although a thorough graphical set of analyses were performed attempting to correlate the difference in mechanical property values to the previously listed variables, and only main variables found to influence strength values were moisture content and specific testing standard employed. The results of the high range of mechanical property values with no variable with which to separate the results to lower the range, led to the second part of the research. It incorporated the high range of values reported in the literature but was able to establish safety factors and reduction factors alongside corresponding failure rates. This work allows for a designer to use bamboo culms choosing a failure rate he/she deems appropriate for structural bamboo construction. The analyses in this work were performed using Allowable Stress Design (ASD) and Load and Resistance Factor Design (LRFD) equations applied to bamboo as well as Monte Carlo statistical analyses for verification. The raw data and statistically analyzed data of 25 publications were used for this analysis, yielding 3806 strength test values (shear strength, compressive strength, bending strength / modulus of rupture, and tensile strength). Shear strength safety factors ranged from 1.38-3.58 for failure ratios from 1:6-1:25000; compressive strength from 1.30-2.79; bending strength from 1.43-4.03; tensile strength from 1.66-7.43. No singular safety factor is suggested for design as that is due to the judgment of the designer of what failure ratio he/she deems appropriate for the specific application. Although many compression tests have been performed on bamboo, there are no known tests which destructively test bamboo after an extended period of time after harvesting (more than ~3 months). This experiment conducted a field experiment to test the functionality of using bamboo for the application of installing bamboo wells to provide groundwater. The bamboo tested in the third part of the study was of two species, Dendrocalamus giganteus and Dendrocalamus asper half of which were 1) air-dried in a laboratory for 3.5 years and the other half of which was 2) inserted in the ground as bamboo wells. The bamboo culms (or poles) had been separately treated in three different ways right after cutting: 1/3 with a borax and boric acid solution (most conventional treatment in the industry), 1/3 with coconut oil (experimental treatment in the literature), and 1/3 air-dried, a non-treated control. Bamboo wells are said to be used in ancient times as well as in more recent applications in the 1990s in India by small scale farmers. The publication of bamboo well studies have been very few and nearly no scientific analyses had been performed on them. Therefore, six bamboo wells were assembled and installed at the University of South Florida Geopark, the first of their kind in the U.S. These wells were half of species D. giganteus and half of species D. asper and also treated individually using the three different treatments described above. The wells were monitored for pH and presence of leached boron for a 3.5-year monitoring period and then removed. Upon removal, the bamboo well casings were examined for molds present as well as by mechanical compression testing to assess degradation in comparison to each other (of different treatments) and to air-dried control samples maintained in the laboratory for 3.5 years. The mold fc. Acrodictys was observed to cover the entire inner portion of the bamboo (inner diameter), from the surface level up to the water table. The lab air-dried control samples had compression strength and compressive modulus of elasticity values correlating to those found in the literature, 44-90 MPa (72 MPa average) and 15-31 GPa, respectively. Removed well samples exhibited compressive strengths and compressive modulus of elasticity values of 22-61 MPa (39 MPa average) and 7-25 GPa, respectively. This study revealed that bamboo wells were feasible and although their compressive strengths lowered by around a half after being in the ground for 3.5 years, their compressive strength and compressive modulus of elasticity values were still in the range of bamboo tested in the literature.
239

Separate treatment of wash water from sand filter using disc filter technology.

González Sánchez, María Fernanda January 2013 (has links)
The purpose of this study is to evaluate the convenience and effectiveness of using a disc filter to treat washing water from the sand filters at Sundet wastewater treatment plant. The disc filter is used aiming for the reduction of suspended solids and phosphorus. The study was divided in two main experimental stages. During the first stage laboratory jar-tests were performed in order to identify which flocculation aid was more suitable, this was further on used to improve the water treatment. Based on the laboratory trials results, two different polymers (1 and 2) were chosen to be tested at pilot scale. The second stage involved the pilot filter operation itself; this period was as well divided in two sub-stages where filter cloths with two different pore openings were tested. During the first sub-stage the pilot operated with an 18 μm pore opening filters cloth and both polymers. At the end of the first half polymer 1 showed to be more efficient and so it was further used throughout the second sub-stage in combination with a 10μm pore opening filter cloth. As from theoretical knowledge the phosphorus and suspended solid removal were expected to be between 75% and 90%, results which were achieved during both laboratory trials and pilot filter. The best results were observed with the 10μm pore opening filter cloth and polymer 1. Also, additional results from pilot trials performed at Sundet after the study period are presented.
240

Utnyttjande av spillvärme och minskade behov av köpt el i biltvättar : En undersökning av Berners miljötvättar i Östersund och Sundsvall / Utilization of waste heat and reduced need for purchased electricity in car washes : A study of Berner's environmental washes in Östersund and Sundsvall

Thorbjörnsson, Ludvig January 2021 (has links)
Berners är en stor aktör inom försäljning och service av bilar och transportfordon i Jämtland och Västernorrland. På sina anläggningar i Sundsvall och Östersund tillhandahåller Berners bland annat biltvättar och rekond och dessa verksamheter ger upphov till stora utsläpp av vatten och kemikalier. För att minska utsläppen har Berners installerat indunstarrening, som är en reningsteknik som bygger på att smutsigt tvättvatten förångas och farliga partiklar faller ur. Med den här tekniken elimineras nästan alla kemikalieutsläpp och ungefär 90 procent av tvättvattnet återanvänds. Indunstarrening kräver mycket energi i form av el som i dagsläget köps in. Reningstekniken ger även upphov till spillvärme i både luft och vatten som i dagsläget inte utnyttjas. Syftet med arbetet är att undersöka potentiella förbättringsåtgärder för Berners biltvättar, för att göra de befintliga och eventuella framtida anläggningar bättre. Detta genom att undersöka möjligheterna av att utnyttja spillvärme och minska behovet av köpt el, genom egenproduktion av el med solceller. Målet är att genom detta ta fram underlag för Berners när de ska besluta om eventuella förändringar av de befintliga tvättarna samt vid byggnation av nya anläggningar. Underlaget ska bestå av resultat för minskade energibehov, minskade utsläpp, minskade behov av köpt el och livstidsbesparingar för förbättringsåtgärderna. I arbetet undersöktes tre olika förbättringsåtgärder. Installation av FTX-ventilation för att värma ingående luft till en angränsande lokal med utgående luft från det rum där indunstaren är placerad, installation av en plattvärmeväxlare för att värma vätskan i en radiatorkrets med utgående destillat från indunstaren samt installation av solceller för att minska behovet av köpt el till indunstaren. Monokristallina-, polykristallina- och tunnfilmssolceller samt olika storlekar av installerad area undersöktes. Minskade energibehov beräknades för FTX och VVX, minskade behov av köpt el beräknades för solceller och minskade utsläpp av koldioxidekvivalenter samt livstidsbesparingar beräknades för alla tre förbättringsåtgärderna. Resultaten visar på att en kombination av att installera FTX, VVX och polykristallina solceller genererar de största livstidsbesparingarna och de största utsläppsminskningarna. Installation av en plattvärmeväxlare för att ta vara på spillvärme i destillat är den enskilt bästa åtgärden för att minska energibehovet. Berners kan vid installation av en eller flera av de olika förbättringsåtgärderna minska energibehoven och utsläppen från biltvättarna, minska behovet av köpt el samtidigt som de kan spara pengar. / Berners is a major player in the sale and service of cars and transport vehicles in Jämtland and Västernorrland. At its facilities in Sundsvall and Östersund, Berners provides, among other things, car washes and auto reconditioning and these operations give rise to large discharges of water and chemicals. To reduce emissions, Berners has installed evaporator treatment, which is a treatment technique based on the evaporation of dirty washing water and the fallout of dangerous particles. With this technology, almost all chemical emissions are eliminated and approximately 90 percent of the washing water is reused. Evaporator cleaning requires a lot of energy in the form of electricity that is currently purchased. The treatment technology also gives rise to waste heat in both air and water, which is currently not used. The purpose of the work is to investigate potential improvement measures for Berner's car washes, to make the existing and possible future facilities better. This is done by investigating the possibilities of utilizing waste heat and reducing the need for purchased electricity, through own production of electricity with solar cells. The goal is to thereby produce a basis for Berners when they are to decide on any changes to the existing washes and when building new facilities. The basis shall consist of results for reduced energy needs, reduced emissions, reduced need for purchased electricity and lifetime savings for the improvement measures. The work examined three different improvement measures. Installation of FTX- ventilation to heat the incoming air to an adjacent room with outgoing air from the room where the evaporator is located, installation of a plate heat exchanger to heat the liquid in a radiator circuit with outgoing distillate from the evaporator and installation of solar cells to reduce the need for bought electricity for the evaporator. Monocrystalline, polycrystalline and thin film solar cells as well as different sizes of installed area were investigated. Reduced energy needs were calculated for FTX and VVX, reduced needs for purchased electricity were calculated for solar cells and reduced emissions of carbon dioxide equivalents as well as lifetime savings were calculated for all three improvement measures. The results show that a combination of installing FTX, VVX and polycrystalline solar cells generates the largest lifetime savings, as well as the largest emission reductions. Installing a plate heat exchanger to take advantage of waste heat in distillates is the single best measure to reduce energy needs. When installing one or more of the various improvement measures, Berners can reduce the energy needs and emissions from the car washes and reduce the need for purchased electricity, while at the same time saving money.

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