Master of Science / Grain Science and Industry / Sajid Alavi / The U.S. pet food market was approximately worth $22 billion in 2013. Further growth is predicted at a pace faster than most major human food product categories. More than 60% of pet food products are processed using extrusion, and a significant proportion is produced using baking. However, research is lacking on fundamental process and product differences between extrusion and baking. The current study focuses on this aspect and also in-depth characterization of process and product quality. Three iso-nutritional diets were formulated for dry expanded dog food using 0%, 7% and 15% fresh meat inclusion. Major variations between diets were inclusion rates of mechanically deboned chicken, cereal grains, and poultry fat. Each diet was processed with a single screw extruder using various thermal and/or mechanical energy inputs (obtained by varying pre-conditioner stem injection and/or extruder screw speeds). Diets were also processed by baking using a 30 foot experimental oven at 425°F, although the fresh meat inclusion was at 0%, 10% and 20% levels. Proximate analysis of products was conducted. Products were also characterized for physico-chemical properties such as bulk density, piece density, expansion ratio, degree of gelatinization and textural attributes. As fresh meat inclusion increased (0–15%), expansion ratio (4.1–3.5) decreased irrespective of extrusion treatment. Expansion was not evident in the baked kibbles, and bulk and piece densities were up to 56% higher for baked versus extruded kibbles. Textural analysis of extruded kibbles revealed serrated force-deformation response, typical of cellular products, with peak hardness of 2.9–1.5 kgf. On the other hand, baked products had a ‘smooth’ force-deformation response with higher peak hardness than extruded products (up to 3 kgf). Microbial counts for baked products were higher than extruded products, and rancidity profiles as obtained from gas chromatography also had marked differences. The extrusion process was characterized by detailed mass and energy balance analyses, and compared with baking that lacks mechanical energy input. Results from this study provide a useful bench-mark for dry expanded pet food product quality and commonly used processing technologies.

Made available in DSpace on 2014-06-11T19:30:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-07-02Bitstream added on 2014-06-13T20:39:47Z : No. of bitstreams: 1 mosckem_sl_me_guara.pdf: 1245042 bytes, checksum: 8a691aa6f65edd8f060ed9355bc9c3bd (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O trabalho de análise do uso de materiais alternativos no Alto Forno 1 da ArcelorMittal Tubarão estabelece uma taxa de substituição de cada material alternativo, plástico e pneu, em relação ao uso exclusivo do carvão mineral injetado no Alto Forno através das ventaneiras. A taxa de utilização de plástico e pneu é avaliada considerando o aporte de energia e dos agentes necessários para a reação química de redução do minério de ferro em ferro metálico. No presente trabalho são elaborados os balanços de massa e de energia de acordo com a configuração operacional vigente no segundo semestre de 2009 para o Alto Forno 1 e com os dados de produção do mês de julho de 2009. O resultado mostra a viabilidade técnica do uso de plástico ou pneu e estabelece as condições de uso de cada um em relação à quantidade, tipo e granulometria. A substituição energética decorrente do uso de plástico e pneu estabelece uma forma de aplicação segura e controlada deste resíduo, além de agregar valor a estes materiais normalmente descartados pela sociedade. Contribui também para amenizar os impactos ambientais decorrentes da falta de uma destinação regulamentada e eficaz para plásticos descartados e pneus inservíveis / The study of alternative fuel materials in the Blast Furnace 1 of ArcelorMittal Tubarão, establishes a rate of each material analyzed, waste plastics packaging and waste tires, in order to replace part of the pulverized coal that is usually injected in to the Blast Furnace through the tuyeres. The injection rate of waste plastic packaging and waste tires is analyzed considering the energy input and the necessary elements for the iron ore reduction chemical reaction. The mass and energy balance is done according to the operational configuration of the Blast Furnace 1 in the second semester of 2009 and operation data from July of 2009. The result of the study shows technical viability to use waste plastics packaging and waste tires and establish requirements for the injection, such as flow rate and particles size. The alternative energy provided from these waste materials builds a safety and controlled way to reach the best utilization for each one. Moreover, the environmental impact can be reduced due to its disposal is normally done in outdoor areas

Under 2014 stod industrin i Sverige för nästan 40% av den totala energianvändningen. Stål- och metallindustrin står för den näst största delen efter massa- och pappersindustrin. En stor del av energin går förlorad som restvärme och betraktas ofta som avfall. Användning av restvärme ger ett minskat behov av primär värme samt minskade utsläpp av CO2. I många fall går restvärmen att använda till fjärrvärme om den har tillräckligt hög temperatur. Det här examensarbetet har tagits form av en fallstudie på stålindustrin Sandvik. Syftet med arbetet är att ta fram en energibalans för en av byggnaderna inne på industriområdet. Ett till syfte är att undersöka om det finns möjlighet att återanvända restvärme från kylsystemet. Byggnaden som har undersökts heter Norra stegvalsverket och verksamheten som bedrivs där är stegvalsning av rör. För att nå målet med arbetet har en litteraturstudie genomförts, fallstudie som har innehållit en del mätningar av flöden och temperaturer samt en mängd intervjuer. För att ta fram en energibalans krävs det att byggandens energiflöden kartläggs. Den tillförda energin kommer i form av el, ånga och internvärme. Energin som bortförs är transmission, ventilation, kylvatten och oavsiktlig ventilation. Arbetet har begränsats till en byggnad och inga tekniska lösningar har undersökts. Resultatet från detta arbete visar att temperaturen på kylvattnet är för låg för att brukas till fjärrvärme om den inte uppgraderas till en högre temperatur. Ett annat användningsområde är att förvärma ventilationsluften med kylvattnet. Arbetet visar också att det finns för lite detaljerad information beträffande elanvändningen. Problemet upptäcktes i arbetets slutskede vilket gjorde att det inte fanns tid att göra ytterligare mätningar. Detta gör att det inte ger en rättvis bild hur energin fördelas i Norra stegvalsverket. För att utveckla detta arbete krävs en noggrann undersökning av elanvändning för att ta reda på exakt hur mycket el Norra stegvalsverket förbrukar. En studie skulle även kunna utföras om det finns tekniska och ekonomiska möjligheter att förvärma ventilationsluften med kylvattnet. / In 2014, industrial operations in Sweden consumed nearly 40% of the total energy use. The steel and metal industry uses the second largest amount of energy in the industrial sector, only the pulp and paper industry uses more. A large part of the energy is waste heat and is often considered as waste. I many cases the waste heat can be used for district heating if it has sufficiently high temperature. This thesis has been taken as a case study at the steel industry Sandvik. The aim of this study is to develop an energy balance for one of the buildings at the plant. Another purpose is to investigate whether there is a possibility to reuse the heat from the cooling system. The building that has been investigated is called Norra stegvalsverket, which is a cold-pilger mill. To reach the goal with this study, a literature study has been conducted, a case study containing some measurements of flows and temperatures, as well as a variety of interviews. To generate an energy balance, it is required that the energy flow of the building is mapped. The energy that is added is electricity, steam, and internal heat. The energy that the building consumes is transmission, ventilation, cooling water, and uncontrolled ventilation. The study has been limited to one building and no technical solutions have been investigated. The result of this work show that the temperature of the cooling water is too low to be used for district heating unless it is upgraded to a higher temperature. One possible application for the cooling water is to preheat the ventilation air. The study also shows that there is too little detailed information regarding the use of electricity in the building. The problem was discovered at the end of the project, which meant that there was no time to make further measurements. Due to this problem, the study does not give a fair picture how the energy is distributed in Norra stegvalsverket. To develop this study, a thorough investigation of the electricity usage is required to find exactly how much electricity the building uses. A study could also be carried out to find out if there are technical and economic opportunities to preheat the ventilation air with the cooling water.

Orientadores: José Euclides Stipp Paterniani, Wolney Castilho Alves / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-18T12:20:53Z (GMT). No. of bitstreams: 1 Jo_AlineChieka_M.pdf: 7050496 bytes, checksum: 391d2c2135292d79283850171019c417 (MD5) Previous issue date: 2011 / Resumo: O uso da água de chuva como fonte alternativa de abastecimento de água é uma prática em grande ascensão, principalmente pela importância no que concerne à conservação dos recursos hídricos. No entanto, comumente o usuário desconsidera o consumo energético que este sistema possa demandar, e dependendo da concepção do mesmo, pode ser considerado um fator relevante na sua aplicação. As concepções e os componentes de um sistema de aproveitamento de água de chuva variam em função da necessidade de cada usuário e da destinação final do uso da água. Existem sistemas simples, que compõem equipamentos básicos de tratamento e reservação, e sistemas complexos que envolvem equipamentos automatizados, estes geralmente demandam energia, como bombas de elevação e sistemas de desinfecção. Diante disso, o presente trabalho apresenta o modelo equacional teórico aplicável para qualquer concepção de sistema predial de aproveitamento de água de chuva, do qual se obtém um índice de valor energético para cada volume de água de chuva efetivamente aproveitada pelo sistema. A partir desse modelo, pode-se também verificar a eficiência e a viabilidade do sistema, tanto na questão conservacionista quanto na econômica. Como exemplo de aplicação do modelo, utilizou-se o sistema predial de aproveitamento de água de chuva instalado no campus do Instituto de Pesquisas Tecnológicas do Estado de São Paulo (IPT), que destina a água de chuva para a lavagem de piso da cozinha e do refeitório do referido local. O índice médio obtido foi de 3,17 kWh/m³, considerado alto, se comparado com sistemas públicos de abastecimento que em média o índice é de 0,60 kWh/m³ e outros sistemas de aproveitamento de água de chuva que é de 0,05kWh/m³. Este alto índice está relacionado com o consumo de energia do sistema de desinfecção por ozônio, e não com o da bomba hidráulica, como se havia suposto inicialmente. O período de retorno do investimento foi de cinco a seis anos. Concluindo, o modelo teórico servirá como ferramenta de avaliação do sistema de aproveitamento de água de chuva em estudo, de forma que o projetista ou usuário consiga otimizá-lo, considerando as particularidades de cada situação / Abstract: The use of rainwater as an alternative source of water supply is a practice on the rise, mainly for its importance in conservation of water resources. However, the user often ignores the energy that this system may require, and depending on its design, can be considered a relevant factor in its application. The conceptions and components of a rainwater harvesting system vary depending on the needs of each user and its final destination. There are simple systems made with basic equipaments and reservation processing, and complex systems involving automated equipments, which generally require energy, such as lifting pumps and disinfection systems. Therefore, this paper presents a theoretical and equational model, applicable at any building to realize a rainwater harvesting system, from which you get an energy value index for each volume of rainwater effectively utilized by the system. From this model, it is also possible to check the system's efficiency and viability, both in conservation and economic question. As an example of an applied model, the rainwater harvesting building system installed on the campus of the Institute for Technological Research of São Paulo (IPT) was used, which directs rain water to wash the kitchen floor and the cafeteria of this site. An average rate of 3,17 kWh/m³ was obtained, considered elevated when compared to public supply systems, that on average attains rates of 0,60 kWh/m³, and other systems with 0,05kWh/m³. This high rate is related to the energy consumption of the ozone disinfection system, not with the hydraulic pump, as had been assumed initially. The payback period is five to six years. In conclusion, the theoretical model will serve as an evaluating tool of the rainwater harvesting system in study, so that the designer or user can optimize it, considering the particularities of each situation / Mestrado / Saneamento e Ambiente / Mestre em Engenharia Civil

Watching television or listening to music during exercise has been shown to increase the enjoyment of the activity and decrease fatigue for some people. However, it is currently unknown how these stimuli during an exercise session play a role in postexercise energy intake and/or physical activity energy expenditure (PAEE). The purpose of this thesis was to examine the effects of watching television or listening to music while exercising on post-exercise energy intake and expenditure in male adolescents. The study consisted of a randomized crossover design involving 24 male adolescents aged 12 to 17 years. The participants completed three experimental sessions that included walking/jogging on a treadmill at 60% of their heart rate reserve for 30 minutes while watching television, listening to music, or exercising with no other stimulus (control). Following the exercise sessions participants were given an ad libitum lunch and were asked to record their food intake for the remainder of the day. An Actical accelerometer was used to assess PAEE until bedtime. The primary outcome measure was post-exercise energy intake and energy expenditure. Results showed that exercising while watching television or listening to music did not significantly affect postexercise energy intake or energy expenditure. Walking/jogging on a treadmill was found to be more enjoyable while watching television than with no stimulus present (p=0.03). Ratings of perceived exertion were not significantly different between conditions. Overall, our results suggest that watching television or listening to music while exercising does not impact post-exercise energy intake or expenditure in male adolescents, which may have positive implications for adolescents who may need additional motivation to exercise.

Compressors are widely used across the all technical fields and current pressure on ecology increases the demand for more effective compressor with economical operation costs. The reasons for inefficiencies must be identified during the development process of a new compressor, where simulation tools might become very useful. There are many different tools for compressor analysis and choosing the right one is mostly dependent on the level of detail that must be analyzed. Models based on energy balance seem to be appropriate when the global parameters of a compressor are demanded. These models offer quick results with reasonable degree of accuracy in terms of basic compressor characteristics. The goal of this thesis is to develop such a simulation tool for a reciprocating compressor. The tool can predict compressor behavior based on compressor dimensions and valve properties. The processes inside the cylinder and heat transfer between the components of a compressor are analyzed using energy balance equation. Simulation tools were verified and experimentally validated using two different types of compressors, therefore they might be used for any reciprocating compressor under some conditions. Mathematical solution was developed in Matlab and therefore it is possible to add new sub-models or to couple the actual model with other simulation tools. This work also contains an analysis of heat transfer models used to predict heat transfer coefficient inside the cylinder and comparison with complex numerical approach. Impact of heat transfer on the compressor efficiency was evaluated too.

This research project investigated the option of steelmaking with the ESS furnace by using computational modelling to estimate steady state decarburisation rates. It focused on understanding metallurgical phenomena that would dictate refining rates of molten pig iron with iron ore. The results obtained are aimed at designers and potential users of the furnace technology to improve their understanding of the expected steady-state process behaviour. A mass-and-energy-balance model with a decarburisation sub-model was developed to estimate feed material requirements for steady state operation. Modelling and simulation results suggest that it may not be possible to produce steel under the conditions proposed. However, the furnace still holds potential if ideal operational conditions are understood and applied. Modelling also gave insight into which areas areas of concern, such as bubble formation in the furnace’s channel induction heaters, and necessity for a well designed refractory lining to contain heat and allow the process to operate at a stable condition under the conditions proposed. Keywords: ESS furnace, steelmaking, metallurgical analysis, modelling, mass and energy balance, decarburisation kinetics / Dissertation (MEng)--University of Pretoria, 2020. / Materials Science and Metallurgical Engineering / MEng / Unrestricted

OBJECTIVE: To investigate the differential association of cigarette smoking with energy balance in African-American and white premenopausal women. DESIGN: Cross-sectional study of energy balance, weight, and smoking in women. SUBJECT: A total of 374 women: 191 African-American (mean age = 29.8 ± 6.5y) and 183 white women (mean age = 28.9 ± 7.1 y). MEASUREMENTS: Weight, cigarette smoking habits, resting energy expenditure, dietary intake, and physical activity. RESULTS: There were no significant differences in dietary intake by race or smoking status. The model for physical activity was significant (P = 0.0004), with body mass index (BMI) having the largest effect on activity (P<0.001). Smoking status was related to activity, with the heaviest smokers reporting more activity than nonsmokers (P= 0.008) or light smokers (P= 0.028). The model for resting energy expenditure (REE) was significant (P<0.0001), with the largest again being BMI (P<0.001). There was also an interaction between ethnicity and smoking status (P<0.0001) such that African-American nonsmokers and light smokers tended to have lower REE than several other groups, most often the African-American moderate heavy smokers. The model for BMI was significant (P<0.0001) with an interaction for ethnicity and smoking status (P = 0.0009). African-American nonsmokers and light smokers had significantly higher BMIs than most of the other groups. CONCLUSION: African-American women who were the heaviest smokers had a lower adjusted BMI than the heaviest smoking white women. This effect, at least partially, may be related to an increased REE in the African-American smoking women. While energy intake did not appear to be important in this relationship, energy expended in physical activity appeared to be increased with smoking, as was REE.

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