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Hassanain, Ahmed A. "Investigation of solar chimneys and tubular transpired solar air heaters as improved systems for solar dryers." Thesis, University of Ulster, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.393770.
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Sotocinal, Samson A. "Design and testing of a natural convection solar fish dryer." Thesis, McGill University, 1992. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=60638.
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A natural convection solar fish dryer consisting of a flat-plate solar collector, drying chamber, and an auxiliary heater was designed, constructed and tested in the Philippines. The dryer is capable of drying 5 kg of fish in 10 hours.Water was first heated in a flat-plate solar collector then through thermosyphon effect, heat and mass was moved to the heat exchanger where heat was transferred to the air. Heated air was allowed to flow through the drying chamber where trays of prepared samples of fish were laid. Pre-drying treatment of fish similar to those used in commercial practice, were used for individual drying experiments in order to permit a general evaluation of the system.
Seven drying experiments using different fish samples were conducted and the data generated was used to determine the efficiency of the system in terms of solar energy utilization. Results indicate that the system function efficiently at a minimal water temperature increase of 10$ sp circ$C, and the dryer operates at a system efficiency of 9 per cent which compares well with the findings of Yu Wai Man (1986) which found that natural convection solar dryers operate in the efficiency range between 7 to 14 per cent.
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Ekechukwu, O. V. "Experimental studies of integral-type natural-circulation solar-energy tropical crop dryers." Thesis, Cranfield University, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.379485.
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Tang, Lisa S. B. Massachusetts Institute of Technology. "The effects of geometrical changes on airflow of developing-world solar fruit dryers." Thesis, Massachusetts Institute of Technology, 2020. https://hdl.handle.net/1721.1/127869.
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Thesis: S.B., Massachusetts Institute of Technology, Department of Mechanical Engineering, May, 2020Cataloged from the official PDF of thesis.
Includes bibliographical references (pages 43-45).
Small fruit-drying operations are becoming increasingly prevalent in the developing world. Many of these operations rely on solar thermal dryers with small fans to induce active air flow, which enhances drying capabilities. This thesis examines the effects of changes in dryer geometry on the air flow within flatbed solar dryers. The interior of a dryer was simulated using Ansys Fluent, and air flow velocity and patterns were observed as the dryer's length, width, and height were varied. It was found that a small fan placed at the dryer's entrance introduces a thin jet of air, which slows and spreads out over the course of the dryer. A steady air flow pattern was reached 4 meters into the modeled dryer. Reducing dryer height was found to increase the air flow velocity at the dryer's center, but not at the dryer's bottom where fruit is usually located. In addition to decreasing dryer height, the study recommends vertically raising the racks of fruit further above the dryer bottom. Air flow consistency across the width of the dryer persisted as an issue through the variations of width and height.
by Lisa Tang.
S.B.
S.B. Massachusetts Institute of Technology, Department of Mechanical Engineering
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Diallo, Alseyni. "A solar fish dryer for the Republic of Guinea." Virtual Press, 1989. http://liblink.bsu.edu/uhtbin/catkey/562780.
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The Republic of Guinea is located on the west coast of Africa at about 11° North latitude. A large portion of Guinea's supply of protein is dried fish. The actual drying method operates under open air, the foodstuff being unprotected from unexpected rains, windborne dirt and dust, and from infestation by insects, rodents, and other animals. More, the deforestation rate is increasing year after year, depleting the source of fuel for drying. Practical ways of drying fish cheaply and sanitarily would be welcome.The present work develops a prototype solar dryer on the basis of natural convection of air. The device is comprised of a glazed flat plate collector, a furnace with translucent walls, and an air tunnel adjoining the two. Air entering the collector is heated and flows into the furnace where energy is absorbed by pieces of fish placed on horizontal racks. The air exits through an opening in the top of the device carrying moisture with it.Using the prototype solar dryer, a fish drying experiment was conducted at the Center for Energy Research, Education, and Service (CERES) at Ball State University. The primary objectives were to investigate drying rates, times, and loads expected for a dryer constructed using simple techniques and materials readily available in the Republic of Guinea. The drying experimental results are in many ways similar to those reported by previous authors.The solar dried product appears to be superior to the product of current drying methods and the foodstuff is protected from infestation or contamination during drying.Future work suggested by the project experience includes refinement of the dryer design and additional fish drying experimentation. An economic analysis would also yield information on the feasibility of widespread use of solar dryers for drying of fish in the Republic of Guinea.Department of Physics and Astronomy
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Serem, Vincent Kipyego Arap. "Forced air solar system for drying of Arabica coffee in Kenya." Thesis, McGill University, 1987. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=63902.
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Bonaparte, Anthony. "Solar drying of cocoa beans (Theobroma cacao) in St. Lucia." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=23384.
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An indirectly heated solar drier fitted with a flat plate collector and a directly heated solar drier were compared with open air sun drying of cocoa beans under field conditions in St. Lucia. Sun drying was conducted on two surfaces, perforated steel and non perforated wood. The methods were examined for the ability to adequately dry fermented beans and effect on quality. Loading rates of 13.5, 26.9 and 40.4 kg/m$ sp2$ were examined.Temperature increases of 15$ sp circ$C and 20$ sp circ$C above ambient were achieved in the indirect and direct drier, respectively. The solar driers were more efficient than sun drying units at removing moisture throughout at loading rates of 26.9 and 40.4 kg/m$ sp2$ but only in the initial stages at 13.5 kg. External mould development was therefore reduced. Open air sun drying on the wooden surface proved more effective in the final stages at 13.5 kg/m$ sp2$.
The dried beans were of similar internal quality despite faster drying in the driers. The various drying methods and loading rates produced beans of similar pH while only loading rates affected titratable acidity differently. The direct solar drier achieved lower final moisture levels at high loads and was the cheaper alternative.
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Starčević, Nikica. "Systematic design and process optimisation of a robot for treatment of biomass in solar dryers." München Oldenbourg-Industrieverl, 2009. http://d-nb.info/994276966/04.
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Silveira, Luciano Roberto da. "Sistema de aquisição de dados utilizando telemetria: aplicação em secador solar de produtos agrícolas." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/11/11131/tde-07022012-145453/.
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A secagem para conservação de produtos agrícolas e alimentícios e feita geralmente com emprego de eletricidade ou combustível fóssil, que incrementa o custo do produto final. Dessa forma, faz-se necessário o desenvolvimento de sistemas que utilizam energia renovável, como a solar, de modo a reduzir custos sem prejuízo na qualidade do produto. Assim, um secador solar de convecção natural misto foi projetado e construído, bem como um sistema de aquisição de dados (SAD) utilizando telemetria, para monitorar temperatura e umidade relativa, ambas do ar, no interior do secador. Para o projeto do secador pesquisou-se na literatura diversos modelos já estudados, a m de reunir idéias para definição de um modelo particular. Apos construiu, um teste operacional foi realizado no secador, utilizando tomate cereja. O SAD foi construído em três partes: o transmissor com os sensores, protegido em caixa selada e afixado ao secador solar; o receptor, acoplado a um PC em local abrigado e cerda de 60 m distante do secador; e o software de aquisição de dados no PC. Os sensores foram fixados em três pontos diferentes do secador e protegidos com pedaços de tubo de PVC. O transmissor permite visualização instantânea de dados num LCD, gravação em cartão de memória SD e transmissão via RF para o receptor/PC. O software no PC e um aplicativo web, permitindo acesso externo e apresentando os dados em forma de gracos, tabela ou ilustração, alem de possuir um sistema de alerta via SMS para temperatura. Em testes de campo, o SAD apresentou bom funcionamento. Houve pouca perda de dados na transmissão, devido a veículos no caminho do sinal RF, e os sensores responderam corretamente as variações do ambiente. O secador apresentou boa resistência as intempéries, e o teste com tomate cereja mostrou que esta operacional.Drying for preservation of agricultural and food products is usually done with the use of electricity or fossil fuel, increasing the cost of the nal product. Therefore, it is necessary to develop systems that use renewable energy such as solar, to reduce costs without impairing the quality of the product. Thus, a mixed-mode natural-circulation solarenergy dryer and a telemetry data acquisition system (DAS) to log air temperature and air relative humidity inside the dryer were designed and built. For the dryer design, in the literature several models already studied were investigated in order to gather ideas for dening a particular model. Once built, an operational test was conducted in the dryer, using cherry tomatoes. The DAS was built in three parts: the transmitter with the sensors, protected in a weather-resistant enclosure and xed in the solar dryer; the receiver, coupled to a PC in a sheltered place; and the PC software data acquisition. The sensors were put at three dierent points in the dryer and xed with PVC pipe pieces. The transmitter allows data instant viewing on an LCD, SD card logging and RF transmission to the receiver/PC. The PC software is a web application, allowing external access and presenting the data in graph, table or illustration, in addition to having an alert system to temperature by SMS. In eld tests, the DAS was worked well. There was little data loss in transmission due to vehicles in the RF signal path, and sensors correctly responded to the changing environment. The dryer had good weather resistance, and the test with cherry tomatoes showed that it is operational.
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Svenneling, Johnna. "Constructing a solar dryer for drying of pineapples : Implementing a solar dryer for sustainable development in Ghana." Thesis, Karlstads universitet, Avdelningen för energi-, miljö- och byggteknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-15737.
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Drying of fruits has been done for many years and different techniques have been developed. For preservation of fruit, drying is a good method for producing sustainable food products that avoids waste. The interest in producing sustainable food products that are nutritious and safe from bacterial growth has increased. In developing countries large amounts of food are destroyed, while many people are undernourished. Every year large amounts of pineapples are produced in Ghana. The pineapples are either being sold fresh or distributed to juice producers. To minimize the wastes and improve the economy in rural areas, drying is an interesting method. The unreliable power supply system is a problem in Ghana. Power failure is frequent. During dry season, sun drying is a suitable method for Ghana, which has a tropical climate with dry and rain seasons. A solar dryer for pineapples has been developed, constructed, modified, tested and implemented in the village Edumafa, in a rural area of Ghana. The only energy source that has been used to dry the pineapples is the sun. Before the trip to Ghana, drying tests were made in a laboratory in Sweden and a prototype of the dryer was built in the university workshop. This was done to facilitate the work in Ghana by gaining experience from drying and constructing. The prototyping also clarified which type of tools that would be needed so the tools could be transported from Sweden. The results from drying pineapple slices at 70°C in an oven in Sweden resulted in slices with hard shells and a soft, moist content (the moisture could not be removed since it became enclosed inside the slices).The conclusion was drawn that the pineapples cannot be dried in such a high temperature. Slices were in good quality when dried at 50°C. Since the citizens in the village Edumafa have never dried pineapples before, it is important for them to learn how to use the dryer and keep it in good working condition. During wet season it is important that the dryer is protected against rain. In the mid of a sunny day, when the temperature in the ambient air was 30°C, the temperature in the drying chamber could be around 50°C. Temperatures over 50°C were possible to achieve and there were no risk for getting to high temperature in the drying chamber. Therefore good drying temperatures can be achieved. To change the economy in considerable proportions for the citizens in Edumafa, a bigger dryer is necessary. The villagers need investment help to afford a bigger dryer of this type. The dryer can minimize losses of pineapples and create bigger incomes if the solar dryer is maintained in good condition and the villagers use it often to dry pineapples.Att torka frukt har gjorts i många år och olika tekniker har utvecklats. Torkning av frukt är en bra metod för att förlänga hållbarheten och minimera spill. Att producera mat som både har en lång hållbarhet, är näringsrik och har låg mikrobiologisk tillväxt har idag blivit mer och mer aktuellt. I utvecklingsländer förstörs stora mängder av mat samtidigt som det finns ett problem med undernärda människor. I Ghana skördas stora mängder ananas varje år och säljs antingen färska eller skickas iväg för juiceproduktion. För att minimera spill och förbättra ekonomin på landsbygden, torkning är en intressant metod. Ett problem i Ghana är det instabila elnätet. Strömavbrott är vanligt förekommande och därför är det bra om torkningen sker med metoder som inte kräver elektricitet. Klimatet är tropiskt med torr- och regnperioder, och soltorkning passar sig bara under torrperioden. En soltork för ananas har utvecklats, byggts upp, modifierats, testats och implementerats i byn Edumafa på den ghanesiska landsbygden. Den enda energikällan som används av torken är solen. Inför resan till Ghana har i Sverige torkförsök gjorts i ett laboratorium samt en prototyp av en soltork byggts upp i universitetets verkstad. Detta för att underlätta arbetet i Ghana genom att få erfarenheter från torkning och byggande. Byggandet har även klargjort vilken typ av verktyg som kan tänkas behövas så att de kan bli transporterade från Sverige. Resultatet av torkförsöken i Sverige visade att vid 70°C blir ananasen bränd på ytan (fukten kan inte transporteras ut eftersom den blir instängd inuti skivorna), vilket gör att ananasen inte går att torka vid en sådan hög temperatur. Ananasskivorna fick bra kvalité vid torkning i 50°C i laboratoriets ugn. Eftersom soltorkning av ananas är något som byborna i Edumafa aldrig har gjort tidigare, är det viktigt att de förstår hur torken fungerar samt att de kan torka ananas på egen hand. Under regnperioden är det viktigt att torken skyddas från regn. Mitt under en solig dag då utetemperaturen är cirka 30°C kan temperaturen i torkkammaren bli cirka 50°C. Temperaturer över 50°C var möjliga att uppnå och det blev aldrig för varmt i torkkammaren. Vilket tyder på att bra torktemperaturer kan uppnås. För att kunna få till stånd en betydande förändring i ekonomin i Edumafa, är det nödvändigt att bygga en större tork. Invånarna behöver ekonomisk hjälp till investeringen för att ha råd med en större tork av denna typ. Torken kan minimera spill av ananas och generera större inkomster, om torken bevaras i ett gott skick och invånarna använder den ofta för att torka i.
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Bogojevic, Ivana. "Construction and simulation of a solar dryer for drying pineapples in Ghana." Thesis, Karlstads universitet, Fakulteten för teknik- och naturvetenskap, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-15166.
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Drying of agricultural products using solar energy is a method for preservation that has been used for centuries all over the world. This method has been effective especially in tropical and subtropical climates, due to the great availability to solar energy. The village Edumafa in Ghana has great cultivation of pineapples but has no post harvest process. A post harvest process as drying of pineapples can increase cultivation and introduce a new product to be sold at the market. This thesis is investigating the possibility of drying pineapples in coastal Ghanaian climate including both experimental method and simulation. A well functioning solar dryer is constructed based on literature study, which after the dryer is studied in simulated environment. Modifications on the model based on the actual dryer are simulated focusing on the temperature and air velocity distribution. The experimental study results in drying pineapple slices corresponding to eight pineapples in two days. Simulation of the solar collector shows that increased temperature at the end of the solar collector can be achieved when decreasing inclination and decreasing the size of the energy storage layer. Simulation of the drying chamber results in improved distribution of temperature and air velocity inside the drying chamber, providing improved drying conditions with increased inlet size and added flow disturbance. Further studies based on this thesis would be a study of adjustable thickness of the energy storage, and transient simulation. Adjustable thickness of the energy storage and air duct on a experimental dryer could improve the drying in undesirable weather conditions, why a study of defining the optimal adjustment thicknesses for different weather conditions could be of interest. Transient simulation of the drying process accounting for the weather change could improve the drying, since the geometry changes could be made and the drying process studied directly in the simulation tool before building the actual dryer. Transient study of the drying process could even study the effect of different thicknesses of the pineapple slices during drying.
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Basso, Diego Morello. "Simulação do sistema de aquecimento de ar de um secador solar híbrido de produtos agroalimentícios usando o TRNSYS." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/163743.
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O presente trabalho tem por objetivo principal apresentar a avaliação térmica, energética e financeira para um sistema de aquecimento de ar de um secador solar híbrido de produtos agroalimentícios, o qual utiliza como fonte de energia a energia solar e uma fonte de energia auxiliar. Dois tipos de fonte de energia auxiliar são utilizados, uma fonte utiliza biomassa como combustível e a outra utiliza energia elétrica. O sistema é composto por um coletor solar térmico, tipo placa plana de exposição indireta, uma fonte de energia auxiliar. O software TRNSYS é utilizado como ferramenta para executar as simulações, tendo como meta alcançar a temperatura do ar de 70°C na entrada da câmara de secagem. Os resultados são apresentados em função das temperaturas da placa absorvedora, do ar de saída do coletor solar e do ar de entrada na câmara de secagem e em função da quantidade de energia, por hora, fornecida para o ar de secagem pelo coletor solar (ganho de energia útil) e pela fonte de energia auxiliar. Calcula-se o custo horário da energia considerando a utilização da biomassa e da energia elétrica, resultando no custo da biomassa equivalente a 42,5% do custo da energia elétrica.Embora os custos com insumos sejam mais baratos para a utilização do sistema com biomassa, a implementação desse sistema é mais cara, sendo viável apenas em longo prazo. O retorno do investimento para o sistema com biomassa ocorre no quarto ano, enquanto que o sistema com energia elétrica obtém retorno no primeiro ano.This work aim to perform thermal, energy and financial analysis for an air heating system of a hybrid solar dryer for agricultural products, which uses as energy source a combination of solar energy and an auxiliary power source. Two types of external auxiliary power source for energy are used, biomass and electric power. The dryer is composed by an indirect flat plate flat plate collector, an external energy source and a drying chamber. The software TRNSYS is used to run the hybrid solar dryer simulations. The simulations goal is for the system to achieve 70°C air temperature at the drying chamber inlet. The results are showed as a function of the absorber flat plate temperature, the solar thermal collector outlet air temperature and the drying chamber inlet air temperature as a function of the energy amount per hour supplied to the drying air by the solar collector (useful energy gain) and by the external auxiliary power source. The energy cost per hour is calculated by assuming each one of the sources, biomass and electric power. It resulted that biomass costs 42.5% of the electrical power total costs. Although the source material costs are cheaper for biomass usage, it implies higher implementation costs, thus requiring long range usage analysis to prove practicable. The biomass system return of investment occurs at the fourth year while at the electrical power system return of investment occurs at the first year.
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El-lamushe, Hassan Yousef. "A numerical and experimental study of a photovoltaic powered solar rice dryer." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0001/MQ31201.pdf.
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Foster, Sean Andrew. "Construction and Performance Testing of a Mixed Mode Solar Food Dryer for Use in Developing Countries." BYU ScholarsArchive, 2013. https://scholarsarchive.byu.edu/etd/3442.
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This study details the construction and performance testing of a mixed mode solar dryer using a combination of direct and indirect solar energy to dry food. One major benefit of this dryer design is its construction. It was simple to construct and was made with low cost materials, to make it feasible for use in developing countries. Previous research has identified several design factors that affect performance and efficiency: product loading density, number of trays, position of the absorber, and chimney type. Performance testing showed that chimney air speeds were not affected greatly by modifying the design aspects of the dryer, with only a small increase occurring when using a box-type chimney. Overall the temperatures were mostly dependent on irradiance, but using a collector-type chimney generally resulted in higher temperatures throughout the dryer. The RH change across the dehydrator was most affected by the number of trays, but the chimney type did have an effect on the RH right at the chimney exit. Efficiency testing showed that product loading density on the trays was tested at 40% and 60% capacity; there was no statistical difference observed for efficiency between the two levels. Our results show that the dryer was more efficient when using the maximum number of trays. The lowest position of the absorber (5 cm from the ground) was found to be most efficient. A box-type chimney was significantly more efficient than the collector-type chimney in this full factorial study.
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MELO, Caio Tácito Miranda Castro Bezerra de. "Desenvolvimento e estudo experimental de um secador solar aplicado na secagem de banana." Universidade Federal de Campina Grande, 2016. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/514.
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Este trabalho apresenta o desenvolvimento e o estudo experimental de um secador solar com foco nas tecnologias apropriadas para a agricultura brasileira, disseminando a cultura das energias renováveis e contribuindo para promoção do desenvolvimento sustentável. Trata-se de um secador solar de exposição indireta, com coletor solar e câmara de secagem. Apresenta como inovações um capacitor térmico no interior do coletor solar e um sistema de movimentação do ar de secagem acionado por energia solar fotovoltaica, para obtenção de convecção forçada. Foi utilizada a relação entre volumes do coletor solar e da câmara de secagem de 5:1 e instalados sensores TH11, que medem a temperatura e umidade relativa do ar de secagem, conectados a uma placa de Arduino. O secador desenvolvido foi submetido a experimentos na secagem de banana prata (Musa Spp.). Foram coletados dados de variação de massa do produto, temperatura e umidade relativa do ar de secagem que permitiram avaliar as curvas de cinética de secagem da banana, a eficiência do processo de secagem e o rendimento térmico do secador solar. As inovações utilizadas permitiram obter temperaturas do ar no interior da câmara de secagem na média de 50ºC ± 5ºC, e umidade relativa do ar de secagem no interior da câmara de secagem na média de 30% ± 5%. O secador solar mostrou-se eficiente, pois, o tempo necessário para a banana atingir os valores de teor de umidade em base úmida em torno de 25%, foi de 840 minutos (14 h), compatível com os tempos relatados na literatura para equipamentos equivalentes. Constatou-se que o processo de secagem se comportou como nos secadores tradicionais com uma média na eficiência mássica do processo de secagem em torno de 83,95%. O Arduino, permitiu a medição de temperatura e umidade relativa do ar de secagem nas entradas e saídas do coletor solar e da câmara de secagem, o que possibilitou a realização do balanço de energia do secador solar, resultando no cálculo do rendimento termodinâmico do secador solar, o qual foi de 28,51% em média, e na obtenção das outras propriedades termodinâmicas do ar de secagem. As curvas de secagem ajustadas ao modelo matemático de Page, apresentaram em média um coeficiente de determinação de 99,06% podendo assim, ser utilizado para predizer o tempo de secagem da fruta até o ponto desejado. É possível concluir que o secador solar desenvolvido atende as demandas necessárias aos processos de secagem de banana, além de ser de baixo custo e de fácil operacionalidade, comparado com equipamentos semelhantes, o que justifica a sua viabilidade.
This paper presents the development and experimental study of a solar dryer with a focus on appropriate technologies for Brazilian agriculture, spreading the culture of renewable energy and contributing to promoting sustainable development. It is a solar dryer of indirect exposure to solar collector and coupled drying chamber, presenting innovations, among which the use of a thermal capacitor inside the solar collector and a drying air drive system powered by photovoltaic solar energy to obtain forced convection. Other innovations were the choice of the relationship between volumes of the solar collector and drying chamber of 5:1 and the installation TH11 sensors that measure temperature and relative humidity, connected to an Arduino board. The dryer developed was subjected to experiments in Silver banana drying (Musa spp.) Which were collected mass of product data, temperature and relative humidity for assessment of drying process efficiency, the drying kinetics curves and the thermal efficiency of the solar dryer and its components. The innovations have enabled used air temperature inside the drying chamber on average 50°C ± 5°C and relative humidity of the drying air in the average of 30% ± 5%. The solar dryer was efficient, because the time required for bananas reach the moisture content values on a wet basis of about 25% was 840 minutes (14 hours) compatible with the times reported in the literature for equipment equivalents. It was found that the drying process behaved as in traditional dryers with an average mass efficiency in the drying process of around 83.95%. The Arduino, guaranteed measuring temperature and relative humidity drying the entrances and exits of the solar collector and drying chamber, which enabled the realization of the energy of the solar drier balance, resulting in the calculation of the thermodynamic efficiency of the solar dryer which was 26.47%, and determination of other thermodynamic properties of the drying air. The drying curves adjusted to the mathematical model of Page, had an average coefficient of determination of 99.06% and can thus be used to predict the fruit drying time to the desired point. The conclusion of this work, the solar dryer developed meets the demands necessary for banana drying processes, in addition to being low cost and easy operation, with efficiency and reliability, compared to similar equipment, which justifies its viability.
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Afriyie, John Kwasi. "Design, simulation and optimisation of a chimney-dependent direct-mode solar crop dryer (CDSCD)." Thesis, De Montfort University, 2007. http://hdl.handle.net/2086/4346.
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Forson, Francis Kofi. "Modelling and experimental investigation of a mixed-mode natural convection solar crop dryer (MNCSD)." Thesis, De Montfort University, 1999. http://hdl.handle.net/2086/4201.
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Silva, Maria Susana. "Destoxicação do farelo de mamona em secador solar." Universidade Federal de Sergipe, 2010. https://ri.ufs.br/handle/riufs/5063.
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The manufacturing process of biodiesel from castor oil produces a byproduct known as pie or meal, which has anti-nutritional characteristics that only allow its use as fertilizer. If there is a chance to detoxify the pie, it can be used as animal feed with high protein content, increasing its value. There are detoxification processes physical, chemical, biological and combined processes. The possibility of physical treatment by the solar dryer becomes attractive because
the process tends to raise the temperature of the bran to about 60 ° C, temperature that eliminates the ricin, a lethal toxin that represents approximately 1.5% of the bran. In the
present work was made a review of the literature about the known processes for the detoxification of castor bean meal, ranging from the use of autoclave until the sun drying.
After the review, was defined as an object to eliminate the toxin ricin, the solar dryer of indirect exposure. Initially, the castor bean meal were separated into samples and measuring
their mass. The initial moisture content and water activity of the samples were identified and these were placed in electric and solar dryers. The results of drying experiments are presented in the form of graphs and tables, with values of temperature, percentage of dry matter, acidity, total moisture, and protein content of ricin eliminated. The results of drying experiments are presented in the form of graphs and tables, with the values of temperatures, percentage of dry
matter, acidity, total moisture, and protein content of ricin eliminated. These data allowed us to observe the optimum conditions of treatment depending on the quality of ricin, concluding that the solar dryer of indirect exposure eliminates part of ricin, but not entirely, because it takes approximately 95 ° C and 6.5 hours of drying to complete elimination of toxin.O processo de fabricação do biodiesel, a partir do óleo de mamona, gera um subproduto conhecido como torta ou farelo, que possui características antinutricionais que só possibilitam sua utilização como adubo. Se houver a possibilidade de destoxicar o farelo, ele poderá servir como ração animal, com alto teor de proteínas, aumentando o seu valor agregado. Existem processos de destoxicação físicos, químicos, biológicos e processos combinados. A possibilidade de fazer o tratamento físico com o secador solar se torna atraente, pois o processo tende a elevar a temperatura do farelo a aproximadamente 60°C, temperatura que elimina a ricina, uma toxina letal que representa aproximadamente 1,5% do farelo. No presente trabalho realizou-se um levantamento bibliográfico quanto aos processos conhecidos para a destoxicação do farelo de mamona, que vão desde o uso de autoclave até a secagem ao sol. Após a revisão, foi definido como objeto eliminar a toxina ricina por meio de secador solar de exposição indireta. Inicialmente, os farelos de mamona foram separados em amostras, com medição de sua massa, umidade e atividade de água iniciais identificadas e colocadas nos secadores elétrico e solar. Os resultados dos ensaios de secagem estão apresentados sob a forma de gráficos e tabelas, com valores de temperaturas, percentual de massa seca, acidez, umidade total, proteínas e teor de ricina eliminado. Esses dados permitiram observar as condições ótimas de tratamento em função do teor de ricina, concluindo que o secador solar de exposição indireta elimina a ricina, mas não totalmente, pois são necessários aproximadamente 95°C e 6,5 horas de secagem para eliminação completa da toxina.
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Crossen, Edward Wayne. "Textural, Color and Sensory Attributes of Fruits and Vegetables Dried Using Electric Forced-Air and Solar Dehydrators." BYU ScholarsArchive, 2017. https://scholarsarchive.byu.edu/etd/6675.
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Direct sun drying is one of the oldest methods of food preservation. A drying method that utilizes solar energy while minimizing negative aspects of sun drying is a solar dryer. However, research about the quality characteristics of fruits and vegetables dried using a solar dryer compared to a traditional dryer is lacking. To measure this, apple, tomato and carrot slices, and grape halves and whole peas were prepared and dried using either a solar or FA dehydrator (FA), Consumer liking was measured using two sensory panels that asked panelists 9-point hedonic questions between like products. Quality differences were analyzed using a TA.XT2 texture analyzer. Color was measured using a Hunterlab colorimeter. There were no significant differences in consumer liking (p<0.05) between drying methods for any fruits and vegetables with regards to overall acceptability. Grapes, tomatoes and carrots all had significant differences in consumer liking with regards to appearance, which correlates well with observed differences in a* values. Consumers liked the aroma of solar-dried peas significantly more. The texture of FA grapes was liked significantly more than their solar counterparts, which likely contributed to consumers significantly ranking the FA grapes higher than their solar counterparts when asked to rank which one they prefer.
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GOMES, Ítalo de Andrade. "Desenvolvimento experimental de um secador solar de frutas com aproveitamento multienergético." Universidade Federal de Campina Grande, 2015. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/485.
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ÍTALO GOMES DE ANDRADE - DISSERTAÇÃO (PPGEM) 2015.pdf: 2168161 bytes, checksum: 897247fa39243206441054b561f5aa4c (MD5)Made available in DSpace on 2018-04-25T12:01:06Z (GMT). No. of bitstreams: 1 ÍTALO GOMES DE ANDRADE - DISSERTAÇÃO (PPGEM) 2015.pdf: 2168161 bytes, checksum: 897247fa39243206441054b561f5aa4c (MD5) Previous issue date: 2015-02-27
Este trabalho expõe o estudo do desenvolvimento experimental de um sistema de secagem direcionado à produção de frutas desidratadas, com uso da energia solar, sob a utilização de duas formas dessa energia, energia solar fototérmica e energia solar fotovoltaica, que se apresenta como alternativa aos secadores comerciais atualmente existentes que usam energia elétrica. No sistema multienergético, a energia solar fototérmica foi utilizada para aquecer o ar ambiente que é o fluido de trabalho no coletor solar, enquanto que a energia solar fotovoltaica foi utilizada para garantir o fluxo deste fluido na câmara de secagem. Para os testes com o secador, foi escolhido o abacaxi, que tem elevado teor de umidade, sendo altamente perecível, e que também se destaca pela alta demanda e rentabilidade no cenário agrícola de frutas. Na concepção do trabalho apresenta-se como o processo de secagem se realiza e quais os equipamentos utilizados para se efetuar essa técnica, bem como, as formas de energia utilizadas. Todos os materiais utilizados são de baixo custo e facilmente encontrados na região. Os testes experimentais foram realizados nas cidades de Campina Grande e Patos, ambas no estado da Paraíba, no período da primavera e verão do ano de 2014. São apresentados os resultados obtidos em cinco testes experimentais, que permitiram a obtenção das curvas de secagem para cada experimento e calculados o rendimento do equipamento e a eficiência do processo de secagem. Os resultados obtidos mostraram que o sistema desenvolvido e testado experimentalmente na produção de abacaxi desidratado funcionou. Esses resultados foram comparados com valores já relatados na literatura e mostraram-se suficientes para produzir um produto final de qualidade elevada, com teor de umidade final na faixa de 20% a 24%. A média do rendimento térmico obtido no equipamento foi de 36%, enquanto que a média da eficiência do processo de secagem foi de 95%. Com a análise dos resultados, ficou comprovada a operacionalidade funcional e construtiva do sistema de secagem multienergético desenvolvido, que contribui para promoção do desenvolvimento sustentável porque utiliza como fonte energética apenas energia de origem solar.
This work presents an experimental study development of a drying system directed to the production of dehydrated fruit, with use of solar energy, in the use of two forms of this energy, photothermal solar energy and photovoltaic solar energy, which is an alternative to dryers commercial currently exist that use electricity. In multi energy system, the photothermal solar energy is used to heat the room air which is the working fluid in the solar collector, while the photovoltaic solar energy was used to ensure the flow of this fluid in the drying chamber. For tests with the dryer, was chosen the pineapple, which has high moisture content and is highly perishable, and that also stands out for the high demand and profitability in the agricultural scenario of fruit. The design of the work is presented as the drying process takes place and what equipment used to perform this technique, as well as the forms of energy used. All materials used are inexpensive and easily found in region. The experimental tests were conducted in the cities of Campina Grande and ducks, both in the state of Paraíba, during the spring and summer of 2014. Are shown the results obtained in five tests which allowed obtaining the drying curves for each experiment and calculating the efficiency of the equipment and the efficiency of the drying process. The results showed that the system developed and tested experimentally in the dehydrated pineapple production worked. These results were compared with values already reported in the literature and shown to be sufficient to produce a final product of high quality final with moisture content in the range of 20% to 24%. The temperature efficiency in the equipment was 36%, while the average drying process efficiency was 95%. With the analysis of the results, it was proved the functional and constructive operation of multienergético drying system developed, which contributes to promoting sustainable development because it uses as an energy source of solar energy only.
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Silva, Tiago Soares da. "Estudo de um secador solar fabricado apartir de sucata de tambor de polietileno." Universidade Federal do Rio Grande do Norte, 2013. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15713.
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Previous issue date: 2013-07-26The scarcity of farmland, reducing the supply of irrigation water and lack of technologies for conservation, makes the globalized world facing serious difficulties in the production of food for its population. The most viable outlet for this dilemma is the dissemination of technologies, economically viable and available to the whole population, for dehydration of perishable foods produced. This paper presents a solar dryer of direct exposure to the production of dried fruit, made from recycled polyethylene drum of 200 liters, used for storing water or trash. The drum was sectioned in half in its longitudinal axis and has its halves together forming a trough-like structure. It describes the processes of construction and assembly of solar dryer proposed, whose main characteristic its low cost, and was designed for use by people with low income, for processing fruits widely available in our region (mango, banana, guava, cashew, pineapple, tomato and others) in dried fruit and flour, contributing significantly to increase the life of these foods. The nuts and flours can be used for own consumption and for marketing jobs and income generation. Tests were conducted to diagnose the feasibility of using solar dryer for the various types of tropical fruits. Were also compared parameters such as drying times and thermal efficiency obtained with the prototype found in the specialized literature in food dehydration. The drying times in the dryer were obtained competitive with those obtained in other models of dryers LMHES developed
A escassez de ?reas de cultivo, redu??o da oferta de ?gua para irriga??o e falta de tecnologias para conserva??o, faz o mundo globalizado enfrentar graves dificuldades na produ??o de alimentos para sua popula??o. A sa?da mais vi?vel para tal dilema ? a dissemina??o de tecnologias, economicamente vi?veis e dispon?veis a toda popula??o, para desidrata??o dos alimentos perec?veis produzidos. Este trabalho apresenta um secador solar de exposi??o direta para a produ??o de frutas secas, fabricado a partir de um tambor de polietileno reciclado, de 200 litros, usado para armazenamento de ?gua ou lixo. O tambor foi seccionado ao meio, em seu eixo longitudinal, e teve suas metades unidas formando uma estrutura tipo calha. Ser?o descritos os processos da constru??o e montagem do secador solar proposto, que tem como principal caracter?stica seu baixo custo, e foi idealizado para uso de pessoas com baixa renda, para o processamento de frutas amplamente dispon?veis em nossa regi?o (manga, banana, goiaba, caju, abacaxi, tomate e outros) em frutas secas e farinhas, contribuindo significativamente para aumentar a vida ?til desses alimentos. As nozes e farinhas podem ser utilizadas para consumo pr?prio e para trabalhos de marketing e gera??o de renda. Foram realizados testes para diagnosticar a viabilidade do uso de secador solar para os diversos tipos de frutas tropicais. Foram tamb?m comparados par?metros como tempos de secagem e efici?ncia t?rmica, obtidos no prot?tipo com os encontrados na literatura especializada em desidrata??o de alimentos. Os tempos de secagem obtidos no secador foram competitivos com os obtidos em outros modelos de secadores desenvolvidos no LMHES
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Anuncia??o, Elenise Barreto Barbosa da. "Utiliza??o de um secador solar para desintoxica??o da torta de mamona." Universidade Federal do Rio Grande do Norte, 2007. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15734.
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Previous issue date: 2007-01-24Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior
It?s been motivating motivated by the current rulers as an energy solution the use of the biodiesel as source of energy, that doesn't damage the environment and promotes the development of the areas where the base plant are grown. The process of production of the biodiesel, starting from the castor oil plant and its derivers, generates a known product as castor oil plant pie that has been used as fertilizer. Once disintoxicated, it can serve as animal ration, because it contains high content of proteins, presenting larger joined value. The disintoxication process, can be obtained through the process of drying the pie with the construction and use of models of dryers capable to elevate the temperature of the castor oil plant pie to approximately 60?C.In this temperature the product tends to eliminate the ricina, with the aid of an aqueous solution of hydroxide of calcium, or still reach higher temperatures to make the disintoxication without a chemical treatment. It was made a bibliographical research about known processes of disintoxication of the castor oil plant pie from the autoclave use to the drying direct exposure to the sun. Starting from the state of the art and identification of the object, it was chosen solar dryers to eliminate the ricina. It was applied two types of solar dryers: the one of solar direct exposure, and the one with concentrador. The castor oil plant pie was separated in samples, with measurement of its initial mass, codified and placed in the dryers. The results were presented in graphs and tables forms, with the values of temperatures noticed. It was noticed the variations of temperature and the relationships analyzed related with the ricina content eliminated from the pie. The analysis of the ricina content was accomplished by Embrapa - Campina Grande, by eletroforese method. The analysis of the result of considering the content of ricina of the samples. It was observed that, we obtained lower rate of ricina in samples that had larger drying time and average value temperature above 60?C. Comparing with the ones submitted to higher temperatures and in a shorter period of time. It was possible to evaluate the efficiency of the dryers in the desintoxication process of the samples, as well as the type of more appropriate dryer for the drying pie process. Finally, it was concluded that the solar dryer with concentrador presents higher values temperatures than the direct exposure one. So, it?s being more opportune applied in the castor oil plant pie drying process. However, more than one hour for drying time is needed
O uso do biodiesel como fonte de energia, que n?o danifica o meio ambiente e promove o desenvolvimento das regi?es que plantam as mat?rias primas para sua fabrica??o, ? uma alternativa energ?tica incentivada pelos atuais governantes. O processo de fabrica??o do biodiesel, a partir do ?leo de mamona e seus derivados, gera um subproduto conhecido como torta de mamona que vem sendo utilizada como adubo. Desintoxicada ela poder? servir como ra??o animal, tendo em vista o alto teor de prote?nas, apresentando, assim, maior valor agregado. A desintoxica??o pode ser obtida por meio do processo de secagem da torta com a constru??o e utiliza??o de modelos de secadores capazes de elevar a temperatura da torta de mamona a aproximadamente 60?C. Ao atingir essa temperatura, o produto tende a eliminar a ricina, com o aux?lio de uma solu??o aquosa de hidr?xido de c?lcio ou ainda atingir temperaturas maiores para realizar a desintoxica??o sem o tratamento qu?mico. Realizou-se um levantamento bibliogr?fico quanto aos processos conhecidos para a desintoxica??o da torta de mamona que v?o desde o uso de autoclave at? a secagem ao sol. A partir do estado da arte e identifica??o do objeto optou-se eliminar a ricina por meio de secadores solares, sendo utilizados dois tipos de secadores o solar de exposi??o direta e o solar com concentrador. A torta de mamona foi separada em amostras, com medi??o de sua massa inicial, codificada e colocada nos secadores. Os resultados apresentados sob a forma de gr?ficos e tabelas, com valores de temperaturas, permitiram que fossem analisadas suas varia??es e as rela??es com o teor de ricina eliminado da torta. A an?lise do teor de ricina foi realizada pela Embrapa -Campina Grande, pelo m?todo de eletroforese. No resultado da an?lise do teor de ricina das amostras, observou-se que aquelas que tiveram maior tempo de secagem e valor de temperatura em m?dia acima de 60?C apresentavam uma menor taxa de ricina em compara??o com as submetidas a maiores temperaturas por um curto per?odo de tempo, assim foi poss?vel avaliar a efici?ncia dos secadores na desintoxica??o das amostras, bem como o tipo de secador mais apropriado para o processo de secagem da torta. Conclui-se, finalmente, que o secador solar com concentrador apresenta valores de temperaturas mais elevados quando comparado com o de exposi??o direta, sendo ent?o mais oportuno na secagem da torta de mamona, por?m ? necess?rio um tempo superior a 1 hora de secagem
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Alessi, Egly Sturion. "Tomate seco obtido por energia solar e convencional a partir de mini-tomates congelados." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/11/11141/tde-26112010-110653/.
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O tomate constitui-se uma das hortaliças mais exploradas cientificamente, devido à sua importância comercial. O tomate pode, através de processamento adequado, dar origem a inúmeros produtos, alguns deles de elevado consumo no Brasil. Depois da boa aceitação do tomate cereja pelo consumidor, um novo segmento de mini-tomate, chamado Grape, começa a despontar nos mercados brasileiros. O destaque é o híbrido Sweet Grape, que está agradando ao gosto do consumidor e animando agricultores que aderiram às experiências com a nova cultivar. Seu teor de sólidos solúveis chega a 10 °Brix e tem menos acidez, comparado a outras variedades, as quais contem entre 4 e 5 °Brix. Nesse trabalho foi avaliado o processo produtivo do tomate seco, a partir de mini-tomates sweet grape, congelados desidratados em secador solar e convencional, visando obter um alimento seguro do ponto de vista microbiológico, físico-quimica, instrumental cor e aceitabilidade) Os tomates cereja tipo Sweet Grape, foram secos até teores de umidade entre 35% e 0%, e observadas suas mudanças em relação aos tomates in natura , e seu comportamento nos períodos de armazenamento após processados de 0, 30, 60 e 90 dias, verificando assim a sua estabilidade. Foi ainda caracterizado o fruto in natura e submetido a um précongelamento para uma previa perda de água facilitando a secagem. A avaliação da qualidade do produto foi realizada através das análises microbiológicas, físico-químicas, composição centesimal e sensorial. Houve diferença significativa entre os secadores, elétrico e solar, para todos os parâmetros analisados, porém não houve alteração significativa para o período de armazenamento. Em relação à avaliação sensorial, o tomate seco ao sol obteve melhor aceitação entre os provadoresThe tomato is one of the vegetables are more scientifically investigated, due to its commercial importance. The tomato can, through appropriate processing, giving rise to numerous products, some of high consumption in Brazil. After the good acceptance by consumers of cherry tomatoes, a new segment of mini-tomato, called Grape, begins to emerge in the Brazilian markets. The highlight is the hybrid Sweet Grape, which is pleasing to the taste of consumers and encouraging farmers adhered to experiment with new cultivars. Your soluble solids content reaches 10 ° Brix and has less acidity compared to other varieties, which contain between 4 and 5 ° Brix. In this study we evaluated the production process of dried tomato, from mini-sweet grape tomatoes, frozen and dehydrated in conventional solar dryer was used to obtain a food safe from microbiological point of view,. physico-chemical, instrumental color and acceptability) Cherry Tomatoes Sweet Grape type, have been dried to moisture contents between 35% and 50%, and observed their changes for tomatoes in nature, and their behavior during periods of storage after processed 0, 30, 60 and 90 days, thus confirming its stability. It was further characterized the fresh fruit and undergo a pre-freeze to a predicted loss of water facilitating drying. Assessing the quality of the product was carried out by microbiological, physicochemical, chemical composition and sensory. There were significant differences between the dryers, electric and solar, for all parameters analyzed, but no significant change for the period of storage. Regarding the sensory evaluation, the sun-dried tomatoes the best won acceptance among judges
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Bauer, Konrad. "Development and Optimisation of a Low-Temperature Drying Schedule for Eucalyptus grandis (Hill) ex Maiden in a Solar-Assisted Timber Dryer." [S.l. : s.n.], 2003. http://nbn-resolving.de/urn:nbn:de:bsz:100-opus-1618.
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Maurer, Claudia Christine [Verfasser]. "Drying of biogas digestate in a hybrid waste-heat/solar dryer and the effect on nitrogen emissions and fertilizer quality / Claudia Christine Maurer." Düren : Shaker, 2020. http://d-nb.info/1222396289/34.
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Maurer, Claudia [Verfasser]. "Drying of biogas digestate in a hybrid waste-heat/solar dryer and the effect on nitrogen emissions and fertilizer quality / Claudia Christine Maurer." Düren : Shaker, 2020. http://nbn-resolving.de/urn:nbn:de:101:1-2020112904252033907640.
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Bauer, Konrad [Verfasser]. "Development and optimisation of a low-temperature drying schedule for Eucalyptus grandis (Hill) ex Maiden in a solar-assisted timber dryer / von Konrad Bauer." Stuttgart : K. Bauer, 2006. http://d-nb.info/982098324/34.
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Silva, Jos? Menezes da. "Viabilidade do uso de secadores solar de convec??o natural e for?ada para a secagem do coco Licuri." Universidade Federal do Rio Grande do Norte, 2012. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15716.
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Previous issue date: 2012-05-23Licuri is a palm tree from the semiarid regions of Bahia State, Brazil. It is an important source of food and feed in that region, since their nuts are commonly eaten by humans and used as maize substitute for poultry feeding. The aim of this dissertation is to study the feasibility for use of natural convection solar dryers and forced being compared with the traditional drying outdoors for drying coconut licuri Syagrus coronate. The study led to the construction of two prototype solar dryer for carrying out experiments proving: model Solar Drying System Direct Exposure to Natural Convection built with wood, has a drying chamber with direct cover transparent glass laminates 4 mm, using techniques for proper isolation of the drying chamber. The two prototypes were comparatively analyzed for performance and drying efficiency with traditional extractive use by the community. Were evaluated the variables: time and drying rates and quality of the final samples of coconut licuri. The fruits were harvested and brought the town of Ouricuri, in the city of Caldeir?o Grande, BA for the experiments comparing the three methods of drying was used a standard load of 4.0 kg The quantitative analysis for the result of the drying rate was found in 74% yield and 44% for natural and forced convection respectively compared with the traditional drying. These drying rates represent variation 3-5 times lower. Drying using forced convection licuri showed better quality, was found in a reddish pulp, representing the quantities that were kept of the nutrient beta carotene, and not notice the flavor change from the previous system, the final cost of construction of this system were higher . The prototypes built competitive advantage and had testified fully to resolve the technical difficulties previously encountered in the production of products made of coconut licuri. Allowing add value and increase their potential use for the fruit extractive communities of semi-arid region of Bahia
O licuri (Syagrus coronata (Martius) Beccari) ? uma palmeira nativa do Brasil, largamente disseminada por todo o semi-?rido do pa?s. O fruto do licuri, conhecido pela mesma denomina??o da palmeira, ? totalmente comest?vel. Apesar do grande potencial nutritivo e oleaginoso do licuri, pouca aten??o tem sido dada para o estudo detalhado do valor nutritivo deste fruto. Nesta disserta??o ser? estudado a viabilidade para utiliza??o dos secadores solar de convec??o natural e for?ada (SSSEICF) sendo comparados com a secagem tradicional ao ar livre, para a secagem do coco licuri. O estudo levou a constru??o de dois prot?tipos de secador solar para a realiza??o de experimentos comprovativos: o Sistema de Secagem Solar de Exposi??o Direta e Convec??o Natural constru?do com madeira, possui uma c?mara de secagem direta com cobertura de lamina de vidro transparente de 4 mm, com utiliza??o de t?cnicas para o correto isolamento da c?mara de secagem e o Sistema de Secagem Solar de Exposi??o Indireta e Convec??o For?ada, fabricado com chapas de a?o galvanizado, tem a c?mara de secagem indireta com cobertura de l?mina de vidro transparente de 6 mm, tendo a utiliza??o de t?cnicas para correto isolamento da c?mara de secagem e a inser??o do equipamento de exaustor e?lico de ar respons?vel direto pela convec??o for?ada de ar da c?mara de secagem indireta. Os dois prot?tipos foram analisados comparativamente quanto ao desempenho e efici?ncia com a secagem tradicional em uso pela comunidade extrativista. Foram avaliados quanto as vari?veis: tempo e taxas de secagem e qualidade final das amostras de coco licuri. Os frutos foram colhidos e trazidos do povoado de Ouricuri, na cidade de Caldeir?o Grande BA, para a realiza??o dos experimentos comparativos entre os tr?s m?todos de secagem foi utilizada uma carga padr?o com 4,0 Kg. A an?lise quantitativa para o resultado da taxa de secagem, foi encontrado rendimento de 74% e 44% para o convec??o natural e convec??o for?ada respectivamente, em compara??o com a secagem tradicional. Essas taxas de secagem representam varia??o de 3 a 5 vezes menor. A an?lise qualitativa das amostras de fruto e das am?ndoas mostrou: que, a secagem utilizando a convec??o natural apresentou boa qualidade para o licuri, por?m foi constatada uma altera??o sensorial no sabor, conhecida como coco velado . A secagem utilizando a convec??o for?ada apresentou melhor qualidade do licuri, foi encontrada uma colora??o avermelhada na polpa, representando que foram mantidas as quantidades do nutriente beta caroteno e n?o se percebeu a mudan?a de sabor do sistema anterior, os custos finais de constru??o desse sistema foram maiores. Os prot?tipos constru?dos obtiveram vantagem competitiva e atestou perfeitamente para solucionar a dificuldade tecnol?gica encontrada anteriormente na produ??o de produtos a base do coco licur?. Permitindo agregar valor e elevar as possibilidades de aproveitamento do fruto pelas comunidades extrativistas da regi?o semi-?rida da Bahia
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Širůček, Vojtěch. "Experimentální sušárna čistírenských kalů." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-231024.
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The master’s thesis is focused on the issue of solar drying of sewage sludge. The sludge management of wastewater treatment plants is described in the first part of this thesis. This theoretical part also deals with description of drying and dryers used for sludge treatment. The second part of the thesis is focused on the experimental solar drying of sewage sludge and the evaluation of the results.
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Aumporn, Orawan. "Contribution à l'étude des performances d'un séchoir serre avec stockage de chaleur dans des matériaux à changement de phase." Thesis, Perpignan, 2017. http://www.theses.fr/2017PERP0032/document.
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Ce travail concerne une étude numérique des performances thermiques d’un séchoir- serre équipé d’une unité de stockage de chaleur solaire dans des matériaux à changement de phase (MCPs). L'unité de stockage de chaleur solaire, placée sous le sol de la serre, est composée d’une couche de MCPs (paraffine) disposée entre une plaque en acier et une couche de béton. L'écoulement de l'air asséchant se déroule par convection forcée et le produit disposé sur les claies du séchoir est la banane (Bananas Musa ABB CV. Kluai "Namwa"). Les équations de transfert de chaleur dans la serre, basées sur la méthode nodale, sont déduites d'un bilan thermique établi pour les différents composants du séchoir-serre. Les transferts de chaleur dans les couches de MCPs et de béton sont décrits respectivement par le modèle enthalpique et l'équation de la conduction. Le modèle de cinétique de séchage de la banane est celui d’Oswin modifié. Les équations de transferts sont résolues par une méthode implicite aux différences finies et les algorithmes de Gauss et de Thomas. Nous analysons l'influence du débit d'air asséchant et de l’irradiation solaire sur les distributions spatio-temporelles des températures des composants de la serre et de l'unité de stockage, la durée de séchage, les efficacités thermiques du séchoir-serre et de l'unité de stockage d'énergie. Cette modélisation est complétée par des simulations du fonctionnement du séchoir serre-unité de stockage de chaleur en utilisant la notion de journée type et les données météorologiques de Nakorn Pathom (Thaïlande) et par une analyse de faisabilité technico-économique. Les résultats montrent notamment que l’unité de stockage de chaleur contribue à la réduction de la durée de séchage et augmente les performances thermiques du séchoir et l’unité de stockageThis work is about a numerical study of the thermal behavior of a solar greenhouse dryer and a heat storage unit in phase change materials (PCMs). The heat storage unit containing of PCMs (paraffin) is disposed between a metal plate and a concrete layer and placed under the floor of the greenhouse. The air drying flows along the greenhouse by forced convection and the products placed on the dryer's rack is bananas (Bananas Musa ABB CV Kluai "Namwa"). The heat transfer equations in the greenhouse are based on the nodal method and deduced from a thermal balance on the different components of the solar greenhouse dryer. The heat transfers in the PCMs and the concrete slab are described by the enthalpy method and the conduction equation, respectively. The banana drying kinetic is described by the model modified of Oswin. Transfer equations are solved using an implicit finite difference method associated to Gauss and Thomas algorithms. We analyze the effects of the air drying volumetric flow rate and the solar irradiance on the temperature distribution of the greenhouse dryer and the heat storage unit, the drying time, the solar greenhouse dryer and heat storage unit efficiencies. This modeling is complemented by simulations of the solar greenhouse dryer with the heat storage unit using the day type and the meteorological data of Nakorn Pathom (Thailand) and by an economic analysis. The results show that the heat storage unit provides the reduction of the drying time and increases the thermal performances of the solar greenhouse dryer and the heat storage unit
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Singh, Narinder Pal. "Experimental and theoretical studies on solar dryers." Thesis, 1989. http://localhost:8080/xmlui/handle/12345678/6400.
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Barsong. "Solar drying of tropical fish in Indonesia." Thesis, 1993. https://eprints.utas.edu.au/18957/1/whole_Barsong1992_thesis.pdf.
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Mathematical models were developed to simulate performance of an indirect solar fish drier. A computer simulation was carried out to predict a drying rate including moisture content and water activity of dried fish. Based on the simulation, a new design of a solar fish drier was constructed and tested in Indonesia.
Salted fish Gulamah (Pseudociena amoyensis) and Pan i Kelapa (Trygon sepheu) were dried over a four day period. Meteorological data and data relating to the fish were measured. The results were compared with prediction from the computer model to assess its validity and limitations. The mathematical model predicted a slightly lower drying rate, final moisture contents and water acitvity of the dried fish than those measured.
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Ray, Rai Ajaipat. "Design,development and performance studies of some solar air heaters and dryers for agricultural applications." Thesis, 1988. http://localhost:8080/xmlui/handle/12345678/6356.
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Nguyen, Vu Lan, and 藍古彥. "A Novel Design of Solar Dryer with Solar Tracking System." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/42538435598731731542.
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碩士崑山科技大學
機械工程研究所
96
In order to ameliorate available solar dryer systems and reduce disadvantagescoming from normal structures, a new design of solar dryer system has been investigated in Mechanical Engineering Department of Kun Shan University of Technology, Taiwan - R.O.C. The system only consists of a collector - chamber and a rotatable reflector which are designed for drying food products. Performance characteristic of the new design shows a high ability of being used by customers for its better drying parameter values compared to those of previous systems. It has been successfully tested in unload mode. Experiments have been performed to investigate the performance evaluation & drying behavior of the system. In comparison with an available solar drying system in Kun Shan University, this new solar dryer is offering a range of temperature closer to desired temperature of specific products (with the same air mass going through chamber) which leads to shorter time of drying. Besides, new structure also helps to solve some disadvantages of previous one such as heat loss, working period, troubles caused by dust in air …
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Ci-Ren, Jlang, and 江啟仁. "Study the Efficiency of Direct Solar Dryer." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/96415625660857558671.
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碩士崑山科技大學
機械工程研究所
102
From the research, it is found the best temperatures for drying fruit are in (40 ℃~70 ℃). The drying box internal temperature must maintained in this suitable range, to have better fruit drying quality. This research will study the efficiency by changing the irradiation surfaces, outlet direction and area, and the storage materials. The internal temperature and the humidity data will be used to compare the dryer efficiency, and compare each case with outdoor drying cases with/without solar irradiation. In each experiment 5 pieces of lemon tablets were selected, and measured the weight difference after the test. In this designed solar dryer, it is found the glass surface would increase the average interior temperatures, outlet direction and area would also influence the average interior temperature and humidity, and finally the stone for the heat storage would improve efficiency. The fruit drying mechanism could be separated by two steps, one is exterior water of the fruit cell which is easily to released by flowing dry air and heating, the other is the inside water of the fruit body, which is hardly to release at normal temperature. In order to have better performance, we found suitable outlet area is necessary to release the humility, and by using glass surface and stone to increase the temperature.
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Shaik, Zuneid Alam. "Design and Development of a Solar Dryer." Thesis, 2009. http://ethesis.nitrkl.ac.in/1126/1/project.pdf.
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A solar cloth dryer was made with the help of available materials.Its efficiency was investigated with respect to how fast it was able to dry up the clothes.Hence a set of experiments were performed to determine the worthiness of this solar dryer.The experiments showed that the dryer works fine as per its objectives.The main advantage of this dryer is that it can work all round the year,with a built-in auxiliary heating system.Also,with no moving parts,it consumes less power than conventional dryers in washing machines.It can easily be built with commonly available materials
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陳勇智. "Drying agro-products by a photocatalyst solar dryer." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/49667891566700904308.
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碩士國立屏東科技大學
食品科學系
92
Closed-type solar dryer has been developed to improve the performance of the traditional solar dryer. High transmittance glasses are used for complementing the heat from solar radiation, and dew-point technology is employed for dehumidify moisture to enhance drying efficiency. In addition, a heat reclaimable system plus TiO2 photocatalyst are designed to reduce contamination of products and improve the energy saving of the designed solar dryer. The results showed that solar drying with heat reclaimable system at 40~42℃ without switching on heater that would save about 67% electricity. The total count number of the drying cabinet is down from 21 CFU/g to 3 CFU/g, even lower to zero, that satisfy the specification of CNS working environment (below 15 CFU/g).The experiment results of the total count number showed that, for pineapple, there is196 CFU/g from hot air drying and 10 CFU/g from photocatalyst solar dryer, and it has higher vitamin C in that; for balsam pear, there is 430 CFU/g from hot air drying and 20 CFU/g from photocatalyst solar drying; for lotus, there is 186 CFU/g from hot air drying solar drying and 10 CFU/g from photocatalyst solar drying. Results of “L” “a” “b” values and sensory evaluation also indicated that the products from the designed solar dryer have the highest acceptance in every respect.
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Elmehri, Mohamed Ali. "Design of a control system for an indirect solar dryer." Master's thesis, 2019. http://hdl.handle.net/10198/23248.
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Mestrado de dupla diplomação com a Université Libre de TunisThis dissertation focus on the control system design of a for indirect solar dryer without any difficulty of utilization with low cost and autonomous. The intended interest group of this model is small farmers who don't have the cash-flow to put resources into new drying innovations however need basic and modest machines to contend in the current market for nuts. In the present work, a multivariable control system using DHT22, BMP280 sensors to measure the drying process parameters of the fig. The Bernoulli equation was established in the Arduino program to calculate the air velocity. The valves designed based on servo motor DS3225. Then, the control of the position of the valve based on the measured sensor parameters and the conditions of the drying process. And for sending the data in real-time to the farmers, the IoT technology was used by the combination of the GSM/GRPS module with the Arduino UNO board. Then, the Blynk application was used to visualize the data, and the ThingSpeak IoT platform for saving the data and analyses the quality of the drying prosses. More than visualization the data in the Blynk application, a notification was added for the farmers in the case of start drying process and overheating condition. According to the outcomes of the Proteus simulation which have been shown by the Blynk application and the ThingSpeak IoT platform, it can conclude that the design of the control system is successfully done.
Cette thèse porte sur la conception d'un système de contrôle pour séchoir solaire indirect sans aucune difficulté d'utilisation à faible coût et autonome. Le groupe d'intérêt visé par ce modèle est constitué de petits agriculteurs qui n'ont pas les liquidités nécessaires pour investir des ressources dans de nouvelles innovations de séchage, mais qui ont besoin de machines basiques et modestes pour lutter sur le marché actuel des noix. Dans le présent travail, un système de contrôle à plusieurs variables utilisant des capteurs DHT22, BMP280 pour mesurer les paramètres du processus de séchage de la fig. L'équation de Bernoulli a été établie dans le programme Arduino pour calculer la vitesse de l'air. Les vannes conçues sur la base d'un servomoteur DS3225. Ensuite, le contrôle de la position de la vanne en fonction des paramètres mesurés du capteur et des conditions du processus de séchage. Et pour envoyer les données en temps réel aux agriculteurs, la technologie IoT a été utilisée par la combinaison du module GSM / GRPS avec la carte Arduino UNO. Ensuite, l'application Blynk a été utilisée pour visualiser les données, et la plate-forme ThingSpeak IoT pour enregistrer les données et analyser la qualité du processus de séchage. Plus que la visualisation des données dans l'application Blynk, une notification a été ajoutée pour les agriculteurs en cas de démarrage du processus de séchage et de surchauffe. Selon les résultats de la simulation Proteus qui ont été montrés par l'application Blynk et la plate-forme ThingSpeak IoT, il peut conclure que la conception du système de contrôle est réussie.
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(7043108), Mingyuan Chen. "Development of Pico Solar Crop Dryer (POD) for Farm Level Grain Drying by Small Holder Farmers in Africa." Thesis, 2019.
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For African farmers, proper drying is considered to be the biggest single factor in determining whether grain can be effectively stored without deterioration. The primary goal of the project is to develop and test the Pico solar crOp Dryer (POD). The overall goal is to improve the POD’s performance, making it acceptable to small holder farmers in Kenya and other developing countries, and positioning it for commercialization. In the POD tests shelled maize was placed in wooden or plastic trays and that were covered with plastic sheets. In the final design, seven small fans of the type used for cooling electronics moved air through the dryer. Power was supplied by a 12 volt, 30 Watt Solar Panel and a 12 volt 7 ampere hour lead acid battery. A charge controller allowed the fans to draw energy from both the solar panel and the battery. The POD was tested at Purdue from 2017 to 2019. The most recent Purdue test on freshly harvested maize was conducted in September 2018. The POD was able to dry 142 kg of 30.1% mc maize to 13.3% in 24.5 hours of drying over 3 calendar days giving an overall drying rate of 0.68 percentage points per hour. The POD dried the maize in 0.84 of the time required to dry maize on a tarp. In the summer of 2018, the components for assembling 5 POD’s were prepared and sent to Kenya for testing. The tests were conducted in Nakuru county in November 2018, and in Trans-Nzoia, Uasin Gishu, and Nandi counties in March 2019. Overall average drying rates for the tests varied, depending on weather conditions, from 0.58 to 0.97 percentage points per hour. A thin layer drying equation was adapted for use in investigating the effects of weather conditions and the airflow rate on the POD drying rate. Adoption of the POD by small holder farmers in Kenya and other developing countries should lead to a reduction in post-harvest losses caused by improper drying. Although testing has been primarily focused on drying maize, it could be adapted for drying other crops.
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Tsai, Fu-Liang, and 蔡福良. "Design and testing of an experimental type solar energy-assisted photocatalytic negative-pressure dryer." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/78132368565240586693.
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碩士國立屏東科技大學
食品科學系
93
The Kyoto Protocol, an international pact aimed at reducing the world's greenhouse gas emissions, came into effect in February 2005. The accord was ratified by 140 nations which pledge to cut gas emissions by 5.2% by 2012 from the 1990 level. As increasing emission of carbon dioxide, the renewable energy such as solar energy has been paid attention by many countries and those countries that are short of energy. In this study, an experimental type solar energy-assisted photocatalytic negative-pressure dryer（SEPND）was developed and tested. It was expected to contribute on the energy saving for food industry. The dryer is consisted of high transmittance glasses used for absorbing the heat from solar radiation. Moisture can be vaporized and removed by the principle of negative-pressure. The design aims to end the drying process in a day-time batch time without using heating sources and it still maintains good quality. Combining the sterilization function of photocatalyst, it can produce the more hygiene dried foods. The results showed that under the average sun radiation 354W/m2 per hour in Pingtung area, the heat collection performanceηis 0.89. The temperature in the cabinet can be in 40-60℃depending on climate condition. The cost saving transferred from 1482W per hour in total area 4.7 m2 of collectors was 4.45 NT dollars. After coating the photocatalyst, the fungus counting in the cabinet was from average 15 CFU/plate to 3 CFU/plate, even lower, which comply with CNS for normal working environment (less than 15 CFU/plate). For the performance test of the dryer, under negative pressure, test samples such as Sergia Lucens , pineapple and papaya are of having fast drying rate, having lower total number count compared that from hot air drying, and being higher acceptance from 〝L〞、〝a〞、〝b〞 values. All the data collected from this experimental type dryer will be used for the development of a scale-up system.
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Carvalho, João Chaves. "Construção e Avaliação Térmica de um Coletor Solar." Master's thesis, 2013. http://hdl.handle.net/10316/99660.
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Dissertação de Mestrado em Engenharia do Ambiente apresentada à Faculdade de Ciências e Tecnologia da Universidade de Coimbra.A necessidade de um crescente recurso às energias renováveis é incontornável. As energias renováveis são fontes limpas de energia. A sua utilização permite reduzir os impactes ambientais, produzindo menos desperdícios, e contribui para um desenvolvimento sustentável da sociedade atual e futura. A energia solar é a fonte mais abundante do nosso planeta e a fonte de todas as energias. As principais formas da energia solar são o calor e a luz. O aproveitamento da energia para aquecimento do ar é obtida a partir de coletores solares térmicos. Esses coletores são utilizados para diversas finalidades como climatização e secagem. A montagem experimental de um coletor solar para aquecimento de ar foi concebida em Coimbra com o objetivo de estudar o desempenho térmico do mesmo. É inovador pois apresenta baixo custo, simplicidade de construção e consiste na utilização de uma matriz porosa metálica como elemento absorvedor, a palha de aço, atravessada por um escoamento forçado de ar. Deste modo o coletor funcionará como um gerador de ar quente, com o intuito de vir a integrar um equipamento futuro, para a secagem de produtos agroalimentares. A ideia principal é estudar as relações entre o comportamento térmico do coletor, a radiação solar e a diferença de temperaturas, sendo fruto de reflexão a possível diminuição de perdas pela cobertura superior do coletor e a maximização da extração de calor da matriz, melhorando assim o rendimento térmico. De acordo com os resultados obtidos nos ensaios realizados o coletor apresenta valores para aquecimento de ar bastante satisfatórios, sendo capaz de aumentar a temperatura em aproximadamente 45ºC. O rendimento térmico médio situa-se pelos 29%, sendo possível melhora-lo efetuando algumas alterações ao nível da constituição e da inclinação do coletor.
The need of an increasing resource to the renewable energy is inevitable. Renewable energies are clean energy sources. Its use reduces the environmental impact, producing less waste and it contributes to a sustainable development of the current and future society. Solar energy is the most abundant source of our planet and the source of all energies. The main ways of solar energy are heat and light. The use of the energy for heating the air is obtained from solar thermal collectors. These collectors are used for various purposes such as air conditioning and drying. The experimental setup of a solar collector for heating the air was designed in Coimbra with the aim of studying its thermal performance. It is highly innovative because it has low cost, simplicity of construction and it consists in using a metal porous matrix as an absorber, steel wool, crossed by a forced flow of air. Thus the collector will work as a hot air generator, in order to integrate a future equipment, for the drying of agricultural food products. The main idea is to study the relationship between the thermal performance of the collector, the solar radiation and the temperature difference, being the result of reflection the possible reduction of loss from the top cover of the collector and the maximizing heat extraction from the matrix, thus improving the thermal efficiency. According to the results obtained in the tests performed the collector shows values for heating the air satisfactory, being able to increase the temperature at approximately 45°C. The average thermal efficiency lies by 29%, being possible to improve it by making some changes in the constitution and the slope of the collector.
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Tripathy, Punyadarshini Punam. "Determination of heat and mass trasfer coefficients from drying pinctics of potato driyed in moccd-mole solar dryer." Thesis, 2008. http://localhost:8080/xmlui/handle/12345678/6239.
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Ching-Wei, Li, and 李慶瑋. "Study The Effectiveness of The Heat Transfer Medias and Cabinet Designs to The Thermo Efficiency of The Solar Dryer." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/96938474070049806079.
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碩士崑山科技大學
機械工程研究所
101
This research in consideration of the optimal temperature for drying of agricultural (65 ° C to 85 ° C), Maintaining the internal temperature of the solar dryer and reduce heat loss and to avoid overheating, deterioration caused by internal drying of agricultural products, will be a different structure and the heat transfer medium for improvement. Study modules produced by entities (prototype of 54cm × 38cm × 52cm solar dryer cabinet), In order to obtain basic prototype temperature parameters, and with the heat flow software, change detail parameters in order to enhance overall efficiency. It changes parameters: heat medium (oil, water), wind speed (1 m / s, 2 m / s, 3 m / s), export ratio of the size (1:1,1:2,1:3,1 : 4,1:5,1:6), natural cooling (heating for 3 hours, cooled for 3 hours), the structure and adjust the speed change ratio of the entrance. Study found that the dryer cabinet interior is dry air, the choice of oil as the heat transfer medium, the dryer cabinet temperature is about 65 ° C to 70 ° C, wind speed of 1 m / s, the wind speed increased by 1 m / s, the dryer cabinet temperature will drop 2 ° C to 4 ° C, therefore, use the size of the opening speed control, can be of different agricultural drying temperature to make adjustments. Software analysis found that the proportion of 1:4 and out vent, dryer cabinet temperature more uniform distribution of temperature difference between the upper and lower temperature is small. Finally, the entity 54cm × 38cm × 52cm plus spoiler, the heat transfer medium oil tank solar dryer for three hours continuous sunshine test (800 W/m2), combined with a temperature measurement system retrieves the data and analysis were compared with the software, its temperature parameters are the same, there is no difference. Verify the correctness of software configuration and thermal efficiency of the dryer cabinet