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Avaliação da operação de biodigestor no processo de digestão anaeróbia de resíduos sólidos orgânicosSchmeier, Nara Paula 20 November 2017 (has links)
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Previous issue date: 2017-11-20 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Petrobras - Petróleo Brasileiro S. A. / PROSUP - Programa de Suporte à Pós-Gradução de Instituições de Ensino Particulares / O processo de digestão anaeróbia tem sido empregado com destaque no tratamento de resíduos sólidos orgânicos, por tratar-se de uma alternativa para amenizar problemas ambientais e também por uma questão energética, visto que possibilita a produção de energia para auxiliar a suprir a alta demanda, em consequência do elevado crescimento populacional e industrial. No entanto, questões relativas a escalas de trabalho, formas de operação, carga orgânica e influência de parâmetros como AGV, alcalinidade e nitrogênio amoniacal (NA) perduram. Desta forma o presente trabalho objetivou avaliar a operação de biodigestor, ao longo de 340 dias, mediante variação de frequências de adição de RSO e cargas orgânicas volumétricas (COV) de 7,98, 7,80, 9,64, 3,28, 4,10 e 5,00 kg STV/m3.d., com média de ST: 339,6 mg/g e umidade: 64%, frente a produção de biogás e CH4. Ademais, também buscou avaliar a influência de parâmetros como AGV, alcalinidade e nitrogênio amoniacal sobre o processo de DA. O sistema experimental foi composto por um biodigestor de câmara única, com volume de 0,28 m³, alimentado com RSO do restaurante universitário e inoculo ambientado a digestão de RSO. O monitoramento do processo experimental foi realizado por meio de caracterização físico-química (pH, DQO, DBO, alcalinidade, AGV, ST, STF, STV, NT, NA, PT e COT) das frações sólidas e líquidas, além da quantificação do biogás (volume e percentual de CH4). O processo de digestão revelou que aplicações de COVs de 3,28, 4,10 e 5,00 kg STV/m3.d. possibilitaram maiores rendimentos de biogás e CH4, em relação a COVs de 7,98, 7,80 e 9,64 kg STV/m3.d. A aplicação continua da COV de 4,10 kg STV/m3.d. apresentou o maior rendimento de biogás e CH4 em função dos STV aplicados, sendo 94,63 NL/kg STV e 45,42 NL/kg STV, respectivamente. No decorrer do processo de digestão, elevadas razões de AGV/Alcalinidade, baixas razões de C/NT e elevadas concentrações de AGV e NA levaram a uma condição de digestão que representou rendimentos reduzidos de biogás e metano. / The anaerobic digestion (AD) process has been used in the treatment of organic solid waste, for being an alternative to ease environmental problems and also an energy issue, since it allows the production of energy to help supplying the high demand, as a result of high population and industrial growth. However, issues concerning work scales, operation forms, organic loads and influence of parameters such as VFA, alkalinity and ammonia nitrogen (AN) to linger. In this way, the objective of this work was to evaluate the biodigester operation, during 340 days, by varying the frequencies of organic solid waste (OSW) and organic loading rate (OLR), of 7,98, 7,80, 9,64, 3,28, 4,10 e 5,00 kg STV/m3.d., with mean de TS: 339,6 mg/g and humidity: 64%, against production of biogas and CH4. In addition, it also sought to evaluate the influence of parameters such as VFA, alkalinity and AN on the DA process. The experimental system consisted of a single chamber biodigester with a volume of 0.28 m³, fed with OSW from a university restaurant and inoculum set to the digestion of OSW. The monitoring of the experimental process was carried out through physicochemical characterization (pH, COD, BOD, alkalinity, VFA, TS, TFS, TVS, TN, AN, PT and TOC) solid and liquid fractions, in addition to the quantification of biogas (volume and percentage of CH4). The digestion process revealed that OLRs applications of 3,28, 4,10 e 5,00 kg TVS/m3.d. allowed higher yields of biogas and CH4, in relation to OLRs of 7,98, 7,80 e 9,64 kg TVS/m3.d. The continuous application of OLR of 4,10 kg TVS/m3.d. showed the highest biogas yield and CH4 as a function of the VTS applied, being 94,63 NL/kg TVS and 45,42 NL/kg TVS, respectively. During the digestion process, high AGV/Alkalinity ratios, low C/N ratios and high concentrations of VFA and AN led to an digestion condition which represented reduced yields of biogas and methane.
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Eliminación biológica de nutrientes en un reactor biológico secuencial.- Caracterización y estimulación de las fuentes de carbono del agua residual urbana.Barajas López, María Guadalupe 05 April 2002 (has links)
Los objetivos de esta tesis doctoral son la caracterización de un agua residual urbana, la prefermentación del agua residual y la optimización de la eliminación biológica de nutrientes en el tratamiento del agua residual en un reactor biológico secuencial (RBS). El agua residual de una zona residencial de Barcelona se caracterizó mediante parámetros típicos de las aguas residuales y, específicamente, mediante los ácidos grasos volátiles (AGV), el potencial de ácidos grasos volátiles (potencial de AGV) y la DQO fraccionada, con el fin de evaluar su aptitud a la eliminación biológica de fósforo. Se desarrolló una modificación del método original del potencial de AGV, que simplifica el procedimiento.Los valores promedio del agua residual afluente fueron: 282 mg/l MES, 472 mg/l DQO, 39 mg/l NT, 30 mg/l N-NH4, 12 mg/l PT, 7 mg/l P-PO4 soluble. Aunque se encontraron valores bajos de AGV (8,5 mg/l) y de la ratio VFA/PT (0,71 mg DQO/mg P), el potencial de AGV (118 mg/l) y la ratio potencial AGV/PT (18 mg DQO/mg P) fueron comparables con los valores recomendados para la eliminación biológica de fósforo. Del análisis del fraccionamiento de la DQO y de los datos del potencial de AGV se concluyó que la mayor parte de la DQO fácilmente biodegradable y, probablemente una fracción de la lentamente biodegradable, se emplearon para la producción de AGV, en la prueba del potencial de AGV.Se diseñó un ciclo complejo de 6 h para optimizar la eliminación biológica de nutrientes (EBN): llenado estático (1 h), llenado anóxico (0,75 h), llenado aireado (0,25 h), llenado anóxico (0,75 h), llenado aireado (0,25 h), reacción aeróbica (1,5 h), reacción postanóxica (0,75 h), decantación (0,63 h) y vaciado (0,12 h). El tiempo de llenado representó el 50% del total, mientras que la aireación supuso el 33% del tiempo del ciclo. El oxígeno disuelto se controló con un regulador PID, con un punto de consigna de 2,0 mg/l. El tiempo de retención hidráulico (TRH) fue de 8 h y el tiempo de retención de sólidos (TRS) de 24 d. El RBS, de 24 litros, se alimentó con el agua residual en dos fases experimentales diferentes. En la Fase 1, el reactor se alimentó con agua residual cruda. En la Fase 2, el agua residual cruda se alimentó a un decantador primario continuo, explotado como un prefermentador (tanque primario activado, TPA) y su efluente se utilizó para alimentar el RBS. En la Fase 1, los valores del efluente fueron: 39 mg/l MES, 87 mg/l DQO, 8.9 mg/l NT, 1.3 mg/l PT. Las concentraciones de nutrientes quedaron por debajo del límite para poblaciones entre 10.000 y 100.000 habitantes-equivalentes. El llenado estático permitió condiciones fuertemente anaeróbicas durante el llenado, lo que mejoró la eliminación biológica de fósforo. Además, la nitrificación y desnitrificación simultánea, junto con la fase postanóxica, permitieron mejorar la eliminación de nitrógeno.En la Fase 2, se diseño y estudió un TPA con el fin de analizar el efecto de la separación de sólidos primarios y de su prefermentación en el funcionamiento del RBS. El prefermentador, de 3 litros, operó bajo las condiciones siguientes: TRH 1,3 h, TRS 5 y 10 d, recirculación 52% y velocidad del rascador 0,5 rpm. El mejor funcionamiento se consiguió con un TRS de 5 d y con el prefermentador cubierto para un mejor control de la temperatura y el potencial de oxidación-reducción. En estas condiciones se observó solubilización de DQO (22 mg/l) y formación de AGV (34 mg/l). Aunque la fermentación acidogénica fue considerable, la producción de AGV alcanzó sólo el 35% del potencial de AGV del agua residual cruda. Este hecho se atribuyó al flujo no completamente mezclado, intrínseco del prefermentador. El efecto de retención de sólidos en el prefermentador predominó sobre el efecto de fermentación y solubilización, y la eliminación de nutrientes se vio perjudicada, especialmente la eliminación de fósforo. Los valores del efluente en esta fase fueron: 28 mg/l MES, 55 mg/l DQO, 11 mg/l NT, y 5.3 mg/l PT.
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Eliminación biológica de nutrientes en un ARU de baja carga orgánica mediante el proceso VIPKnobelsdorf Miranda, Juliana 14 July 2005 (has links)
El objetivo principal de esta tesis doctoral es profundizar en el conocimiento de los procesos biológicos responsables de la eliminación simultánea de nitrógeno y fósforo en un ARU de baja carga orgánica, mediante un reactor de flujo continuo del tipo Virginia Initiative Plant (VIP). Se han evaluado los parámetros limitantes del proceso y las formas de promover la disponibilidad de la materia orgánica fácilmente biodegradable para los OAF. Se ha llevado a cabo una caracterización de los parámetros físico-químicos del ARU, así como de sus fuentes de carbono, incluyendo la aportación de un sustrato externo, con el fin de determinar y estimular su aptitud para la EBIF. Se ha sistematizado el fraccionamiento de la DQO y la estimación del contenido de AGV y del potencial de AGV, mediante el desarrollo de una alternativa del método original para valorar el potencial de AGV, que simplifica el procedimiento operativo. Aunque el contenido de AGV fue bajo, el potencial de AGV y la fracción potencial AGV/PT fueron comparables a los valores recomendados para la EBIF. La mayor parte de la DQOFB y una fracción de la DQOLB se transformaron en AGV durante el ensayo del potencial de AGV. La aportación de acetato sódico permitió aumentar y mantener un porcentaje medio de AGV del 74% de la DQOFB, del 42% de la DQOs y del 20% de la DQO. La DQO del afluente sin decantar estuvo compuesta mayoritariamente por DQOBT (75% DQOLB y 25% DQOFB). Los incrementos de la DQOFB se tradujeron en incrementos de la DQOs. La mayor parte de la DQOLB del afluente estuvo formada por materia orgánica particulada, haciendo que la presencia de MES en el afluente fuera determinante para incrementar la aportación de DQOLB al sistema.Los rendimientos de eliminación fueron del 85% de la MES, el 87% de la DQO, el 99% del amoníaco y el 42% del P. La mayor eliminación de DQO se registró en la zona anaerobia, con independencia del grado de subdivisión del reactor. La DQO residual se eliminó progresivamente en las siguientes zonas del reactor (89%, 3,8%, 1,7% y 2,2%). La fracción F/M en la zona de contacto inicial estuvo determinada en gran medida por la subdivisión aplicada al reactor biológico.La mayor concentración de PT del efluente se registró los días con mayor recirculación de nitratos al reactor anaerobio y aquellos con episodios de bulking, debido a la adición de un exceso de sustrato. Concentraciones de nitratos en el afluente al reactor anaerobio superiores a 0,20 mg N/L se tradujeron en una liberación de fósforo inferior a 1 mg P/L. A medida que el flujo de nitratos recirculados al reactor anaerobio aumentó, la liberación de P registró una disminución progresiva, rebajando su asimilación posterior en el reactor aerobio. El valor medio de la fracción DQO/PT en el afluente fue inferior al recomendado en la bibliografía (77 mg/mg) para una óptima eliminación simultánea de nutrientes. La fracción DQO/PT máxima (72 mg/mg) se alcanzó agregando un sustrato externo fácilmente biodegradable. La menor concentración de P del efluente se alcanzó con valores altos de la fracción DQO/PT. La relación consumo/liberación de P registró un valor medio de 1,14, si se incluye la liberación en los reactores anaerobios y anóxicos, y de 1,57 si sólo se tiene en cuenta la liberación en el reactor anaerobio. La eliminación de P disminuyó cuando la adición de acetato sódico alcanzó 150 mg DQO/L, debido a un deterioro rápido de la decantabilidad del fango por formación de bulking. La asimilación de P en la zona aerobia fue proporcional a la liberación de P en la zona anaerobia. La liberación de P en la zona anóxica pudo ocurrir como resultado de la fermentación de una fracción de la DQOLB presente en esta zona. / The main objective of this thesis is to advance the knowledge of the biological processes for simultaneous removal of nitrogen and phosphorous from a low-strength municipal wastewater using a continuous flow reactor, based on a Virginia Initiative Plant (VIP) design. An evaluation was conducted of the limiting parameters of the process and the strategies for promoting the availability of easily biodegradable organic matter to the PAO microorganisms. A follow-up was conducted of common wastewater physico-chemical parameters, and its sources of carbon, including the contribution from an external substrate, to determine and promote its potential for the enhanced biological phosphorus removal (EBPR) process. A new protocol was developed for COD fractionation, and for estimating the VFA concentration and the VFA potential, using a modified VFA potential test that simplifies the original operating procedure.Although the VFA content was generally low, the values of the VFA potential and the VFA potential/P ratio were comparable to those required by the EBPR process. Most of the RBCOD and a fraction of the SBCOD were readily converted to VFA during the VFA potential test. The addition of sodium acetate contributed to increase and maintain a mean percentage of VFA at 74% of the RBCOD, 42% of the SCOD and 20% of the COD. The COD of the unsettled influent was mainly formed by TBCOD (75% SBCOD, and 25% RBCOD). Increments of RBCOD translated into increments of SCOD. Most of the influent SBCOD corresponded to particulate organic matter, making the influent TSS content a determining factor for increasing the SBCOD contribution to the system. The removal efficiencies were 85% for TSS, 87% for COD, 99% for ammonia, and 42% for P. The highest COD removal efficiencies were observed in the anaerobic zone, regardless of the reactor subdivision arrangement adopted. The residual COD was removed in subsequent zones of the reactor (89%, 3.8%, 1.7%, and 2.2%). The F/M ratio in the initial contact zone was largely determined by the reactor subdivision adopted. The highest effluent TP concentration was observed during the days with the largest nitrate recirculation rates to the anaerobic reactor, and also during bulking episodes generated by an excessive substrate addition. Influent nitrate concentration to the anaerobic reactor higher than 0.20 mg N/L resulted in a phosphorous release lower than 1 mg P/L. As the recycled nitrates flow to the anaerobic reactor increased, the phosphorous release rates showed a steady decrease, preventing its subsequent uptake in the aerobic reactor. The mean influent COD/TP ratio was lower than that recommended in the literature (77 mg/mg) for an optimum simultaneous nutrient removal process. The maximum COD/TP ratio (72 mg/mg) was reached by adding an easily biodegradable external substrate. The lowest effluent P concentration was observed with high values of the COD/TP ratio. The mean P uptake/release ratio observed was 1.14, when P release from the anaerobic and anoxic reactors was included, while it reached 1.57 when only the release at the anaerobic reactor was considered. Phosphorous removal decreased when sodium acetate addition reached 150 mg COD/L, due to a rapid deterioration of the sludge settling properties caused by bulking. Phosphorous uptake in the aerobic zone was proportional to P release in the anaerobic zone. Phosphorous release in the anoxic zone may have occurred by partial fermentation of the SBCOD input to this reactor zone.
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Gaffeltruckfri produktion : En studie genomförd vid Volvo Construction EquipmentWernberg, Markus, Åstrand, Olof January 2011 (has links)
Volvo Construction Equipment är en del i koncernen Volvo Group. Volvo Group som är en av de ledande aktörerna i världen på transportlösningar. Volvo Construction Equipment utvecklar och tillverkar anläggningsmaskiner i samtliga världsdelar utom Afrika och Oceanien och levererar produkter till kunder över hela världen. I Braås i Småland finns Volvo Construction Equipments huvudanläggning för utveckling och tillverkning av ramstyrda dumprar, inom vilket segment de är världsledande. Gaffeltrucken är den maskin som orsakar flest anmälda arbetsplatsolyckor i Sverige och i snitt anmäls cirka 750 olyckor per år. Företag har med anledning av denna säkerhetsrisk och produktivitetsbegränsningar i allt större utsträckning börjat studera alternativa lösningar för den interna materialhanteringen. De svenska lastbilstillverkarna Volvo Trucks och Scania har redan startat sitt arbete mot målet att uppnå en gaffeltruckfri verksamhet, ett mål som också Volvo Construction Equipment eftersträvar. Under de senaste åren har Volvo Construction Equipment strävat efter att minska riskerna i produktionsanläggningarna. Detta arbete har sin utgångspunkt i arbetet med Lean Production i det system som de väljer att kalla Volvo Production System. Syftet med studien är att ta fram alternativa materialhanteringslösningar för att uppnå en gaffel-truckfri produktion, i enlighet med Volvo Construction Equipments arbete med Volvo Production System. De fem alternativa materialhanteringslösningar som tas fram i studien är automatlager, dragtruck, AGV, transportbana och kran. Utifrån en kartläggning av samtliga truckar, som inte väljs bort på grund av avgränsningar, genomförs en analys. Analysen genomförs i två steg och utgår ifrån de fem olika alternativa lösningarna som kan implementeras. Den första analysen fokuserar på varje enskild trucktyp och vilka alternativa lösningar som kan vara aktuella att använda medan den andra analysen fokuserar på helheten och att få alla lösningar att passa ihop med varandra. Anläggningen i Braås delas in i tre övergripande områden i kartläggningen och analyserna, dessa är materialcentrum, montering och detaljtillverkning. I materialcentrum framkommer att lösningarna som krävs för att uppnå en gaffeltruckfri produktion är att införa två stycken automatlager. Ett enbart avsett för pallar och ett avsett för pallar och smallbox. Lagret för pallar och smallbox ska även vara utformat på ett sådant sätt att plockning kan ske av artiklarna längst ner i ställagen. Kranarna i automatlagret förser sedan automatiskt dessa plockplatser med material från buffertplatser högre upp i ställaget. För att material ska kunna lagras in och plockas ut ur automatlagren på ett effektivt sätt krävs att ett avancerat rullbanesystem installeras. För att försörja monteringsstationerna med material från materialcentrum utan att använda gaffel-truckar är den bästa lösningen att dragtruckar används. Detta då utvecklingen i fabriken, i enlighet med Volvo Production System, eftersträvar ett mer kontinuerligt materialflöde med mer kitning och sekvensläggning. Genom att använda dragtruckar kan ett flertal vagnar med material dras ut på en och samma gång. Detta ökar både säkerheten och produktiviteten. Genom att mer material presenteras i kit eller sekvens förkortas monteringstiden samtidigt som materialet kräver mindre yta vid monteringsstationerna. Detta tillsammans med att materialfasaderna blir mer flexibla medför att en mer effektiv produktion kan utföras. I detaljtillverkningen krävs det ett förändrat arbetssätt för att en gaffeltruckfri produktion ska kunna uppnås. Det krävs att denna materialförsörjning, i likhet med den till monteringen, börjar plockas i kit och sekvens. Därmed kan materialfasaderna bli lägre och mer flexibla vilket medför att layouten kan förändras på ett sätt så att dragtruckar även kan försörja denna del i anläggningen. Samtliga gaffeltruckar går dock inte att ersätta enligt studien. De truckar som hanterar tunga detaljer kommer att finnas kvar tillsvidare då ingen av de analyserade lösningarna uppfyller kraven på ökad säkerhet och ökad produktivitet. I denna studie analyseras 35 stycken gaffeltruckar, 30 av dessa ersätts av alternativa materialhanteringslösningar. / Volvo Construction Equipment is a part of Volvo Group that is one of the leading providers of transport solutions. Volvo Construction Equipment develops and manufactures construction equipment in all continents except Africa and Oceania and delivers products to customers worldwide. The main facility for developing and manufacturing articulated haulers, a segment where they are world leaders, is located in Braås in Småland. The forklift is the machine that causes the most reported workplace accidents in Sweden, in average 750 accidents are reported each year. Companies have, because of the safety issue together with productivity constraints, increasingly begun to study alternative solutions for the internal material handling. The Swedish truck manufacturers Volvo Trucks and Scania have already started their work towards the goal of achieving a forklift free production, a goal that also Volvo Construction Equipment aims for. In recent years, Volvo Construction Equipment has strived to reduce the safety risk in production sites. The safety risk reduction is based on Lean Production and the system called Volvo Production System. The purpose of this study is to develop alternative material handling solutions to achieve a forklift free production, in accordance with Volvo Construction Equipment’s work with Volvo Production System. The five alternative material handling solutions that are developed in this study is automated storage, towing truck, AGV, conveyor and crane. An analysis is conducted based on a mapping of all forklifts that have not been rejected because of limitations in the study. The analysis is conducted in two steps and is based on the five different alternative solutions. The first analysis focuses on each forklift type and the alternative solutions that may be relevant to use, while the second analysis focuses on the big picture and how to get all the solutions to fit together. The plant in Braås is divided into three general areas in the mapping and the analysis, these are materials center, assembly and detail production. In materials centre it is concluded that the solutions that is required to achieve a forklift free production is to install two automated storages. One of them only used for pallets and the other one used for both pallets and smallbox. The storage for pallets and smallbox should also be designed in a way that picking can be performed from the lowest levels in the storage. The cranes in the automated storage should automatically provide the picking levels with material from a buffer, located in higher levels in the storage. If input and output to and from the storage should work properly an advanced conveyor system is needed to be installed. To supply the assembly stations with material from materials center without using forklifts the best solution is to use towing trucks. This solution is also in line with the general work in the factory, according to Volvo Production System, that strives for a more continuous material flow with more kiting and sequencing. By using towing trucks a number of wagons can be delivered to the assembly line at once, leading to an increase of both security and productivity. If the material is more often presented in kit or sequence the assembly time will decrease. Also the area needed for the material at the assembly stations will decrease. This, together with more flexible storage racks enables a more efficient production to be performed. It is necessary for the detail production staff to change their way of thinking and working with the material handling to allow a forklift free production. It is required that the material, in similarity with the material in the assembly, is picked in kits and sequences. This enables the storage racks to be lower and more flexible so that the layout can be changed in a way that allows the towing trucks to supply even this area. This study concludes that all forklifts are not possible to replace. The forklifts handling heavy components will continue to be used. This because none of the analyzed solutions meets the demands of increased security and increased productivity. In this study 35 forklifts are analyzed, 30 of those are replaced with alternative material handling solutions.
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Modelo fuzzy cascata multiatributos e preditivo para despacho de AGVs em FMSCaridá, Vinicius Fernandes 02 May 2016 (has links)
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Previous issue date: 2016-05-02 / In recent years, manufacturers are increasingly applying automation techniques with the aim of
increase their efficiency to remain competitive. The material handling is an essential activity in any process of production and its effectiveness has severe impacts on production costs. Systems of automated guided vehicles (AGVs) have become an important strategic tool for factories and automated warehouses. In a very competitive business scenario, they can increase productivity and reduce costs. The management of these AGVs is the key to a transport system that ensures the improvements envisioned by the industry. One of the main problems encountered in the management of AGVs is the dispatch decision. This paper proposes a vehicles dispatch model based on a fuzzy cascade system for consideration of multiple attributes of the factory and a structure based on state space that enables the extraction of information of future states of the industrial production system.
The objective is to reduce makespan and tardiness values of the production system. Two factory scenarios are simulated and tests are performed of the model and five other methods of dispatch. A statistical validation is realized of the results in which corroborates with 97% confidence the hypotheses of the work. / Nos últimos anos, as indústrias vêm cada vez mais aplicando técnicas de automação com o objetivo de aumentar sua eficiência para manterem-se competitivas. O manuseio de materiais é uma atividade essencial em qualquer processo de produção e sua eficácia tem impactos severos sobre os custos de produção. Sistemas de veículos autoguiados (AGVs) tornaram-se uma ferramenta estratégica
importante para fábricas e armazéns automatizados. Em um cenário de negócio muito competitivo, eles podem aumentar a produtividade e reduzir os custos. O gerenciamento desses AGVs é a chave
para um sistema de transporte que garanta as melhorias vislumbradas pelas indústrias. Um dos
principais problemas encontrados no gerenciamento dos AGVs é a decisão de despacho. Esse trabalho propõe um modelo de despacho de veículos baseado em um sistema fuzzy cascata para ponderação de múltiplos atributos da fábrica e em uma estrutura baseada em espaço de estados que permita a extração de informações de estados futuros do sistema de produção fabril. O objetivo é reduzir valores de makespan e tardiness do sistema de produção. Dois cenários de fábrica são simulados e são realizados testes do modelo proposto e cinco outros métodos de despachos. É realizada uma validação estatística dos resultados em que se corrobora com 97% de confiança as hipóteses do trabalho
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Arquitetura holônica de controle para o despacho multicritérios de AGVsMontoro, Flavio Aldrovandi 02 April 2015 (has links)
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Previous issue date: 2015-04-02 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / In manufacturing, the search for new techniques to improve the production is always a challenge.
These techniques must be adapted to the dynamic environment. A point very dealt in this area is the transportation system which has, as one of its sub problems, the assigning tasks to the AGVs. To solve this problem, it is common to use vehicle dispatching, and these techniques are usually multicriteria. Although they are multi-criteria, is not common contemplate criteria of different sectors of the factory, which could indicate conflicting strategies. Another point that influences the performance of the manufacturing is the control architecture. Traditionally, this architecture is centralized or decentralized, and have pros and cons. To achieve benefits from both traditional architectures, new architectures have been pursued; a widely used option is the holonic. This research presented a holonic architecture control for the dispatch of vehicles using multiple criteria rules, given optimization criteria from different sectors of the factory and providing a global optimization bias. Analyzes were performed to assess the adhesion of the proposed holonic architecture in the manufacturing environment, achieving the inclusion of new elements naturally,
analyzing the behavior when an unpredicted event occurs and enabling compliance with different optimization variables belonging to different sectors of the factory. / Na manufatura, a busca por novas técnicas para melhorar a produção é sempre um desafio. Estas
técnicas devem se adequar ao ambiente dinâmico da manufatura. Um ponto tratado neste âmbito é o sistema de transporte, que tem como um de seus subproblemas a atribuição de tarefas para os AGVs. Para a resolução deste problema, é comum utilizar técnicas de despacho de veículos, sendo que estas técnicas geralmente são multicritério. Apesar de serem multicritério, não é comum contemplarem critérios de diferentes setores da fábrica, o que poderia indicar estratégias conflitantes. Outro ponto que influencia no desempenho da manufatura é a arquitetura de controle. Tradicionalmente, a arquitetura é centralizada ou descentralizada, apresentando prós e contras. Existe uma busca sobre novas arquiteturas para atingir benefícios proveniente das duas tradicionais; uma opção muito usada é a holônica. Neste trabalho é apresentada uma arquitetura holônica de
controle para o despacho de veículos usando regras multicritério, atendendo critérios de otimização de diferentes setores da fábrica e proporcionando um viés de otimização global. Foram realizadas análises para avaliar a aderência da arquitetura holônica proposta no ambiente de manufatura, atendendo à inclusão de novos elementos de maneira natural, analisando o comportamento diante de eventos não programados e possibilitar o atendimento de diferentes variáveis de otimização
pertencentes à diferentes setores da fábrica.
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Reengenharia de um SFM didático com o desenvolvimento de um sistema supervisório e a automoção de um AGV / Reengineering of an didactic FMS with the of development a supervisory system and automation of an AGVSérgio Ricardo Pacheco 30 April 2011 (has links)
Este trabalho tem por objetivo atualizar um Sistema Flexível de Manufatura, (SFM) didático, que devido às suas características construtivas apresentava inúmeras dificuldades de operação e manutenção, necessitando sempre de mão de obra altamente especializada. As dificuldades com a manutenção tornavam o SFM totalmente inoperante para a utilização nas aulas de uma das unidades da escola SENAI, o que prejudicava as atividades práticas, em laboratório, das disciplinas do curso técnico da área de produção. O projeto deste trabalho consistiu em uma reengenharia completa da parte elétrica de um Veículo Guiado Automaticamente (AGV) como também no desenvolvimento de um sistema supervisório, que comanda a comunicação entre os CNCs, AGV e computadores. Após as modificações efetuadas, os alunos das disciplinas da área de produção poderão interagir com o sistema, modificando a logística de produção conforme as necessidades didáticas a serem estudadas. Por outro lado os alunos de automação, por meio do acesso à documentação e à estrutura do sistema de manufatura, poderão desenvolver estudos e possíveis modificações, uma vez que o sistema se tornou mais didático e amigável. / This paper aims to update a didactic Flexible Manufacturing System (FMS) that due to their construction had numerous difficulties in operation and maintenance, and so constantly require manpower to operate and maintain highly specialized. The difficulties with maintaining the SFM became totally irrelevant, for use in the classroom of an unit school SENAI, would hinder the practical activities in the disciplines of laboratory technician course from the production area. The design of this work consisted in re-engineering of the complete electrical part of an Automatically Guided Vehicle (AGV) and development of a supervisory system and communication between the CNCs, AGV and computers. After the modifications to the students of the disciplines of production may interact with the system by modifying the production logistics as required didactic to be studied. Furthermore students automation through access to documentation and structure of the manufacturing system can develop studies and possible changes, since the system became more didactic and friendly.
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A Contingency Framework for Assessing the Commercial Potential of Utility-scale AgrivoltaicsLarsson, Filippa January 2023 (has links)
Purpose - In the pursuit of renewable energy sources, solar photovoltaic (PV) is predicted to become the single biggest global source of energy by the year of 2027, part of a trilemma involving climate change, biodiversity and food security. Agrivoltaic (AV) systems, the co-location and potential symbiosis between agricultural activities and solar PV, has thereby arisen as a potential solution for dual land-use. The research within this area is novel, and scholars agree that there is a need for the conceptualization of utility-scale AV in general, and the commercialization process of such systems in particular. Thereby, the purpose of this study is to unravel the key factors, activities and stakeholder involvement in order to assess the commercial potential of utility-scale AV. By addressing research questions: RQ1. What are the key factors for assessing the commercial potential of utility-scale AV?, RQ2. Which activities are essential to address these factors? and RQ3. Who are the key stakeholders that need to be involved in these activities?, a contingency framework for the assessment process has been developed. Method - In order to fulfill the purpose of this study utility-scale AV was approached as a Technology Innovation System (TIS) where the solar energy actor Sunna Group AB (Sunna) enabled insight to the potential industry context of utility-scale AV. Respondents were sampled within the TIS, forming the prerequisites for this multiple case study. Empirical data were collected in three phases: 1) Exploratory, 2) Semi-structured and 3) Final workshop, resulting in 3 workshops and 17 interviews, analyzed by a thematic analysis. Findings - The thematic analysis resulted in four main themes: 1) Socio-political factors, 2) Techno-economical factors, 3) Meso activities for commercialization and 4) Macro activities for commercialization, under which seven key factors, six overarching activities and the stakeholder involvement in these activities, were revealed. These further formed a contingency framework providing an overview of how these building blocks are interlinked. Theoretical & practical implications - The resulting framework provides an overview and synthesizes the commercialization of utility-scale AV, bridging the gap between stakeholder involvement and the key factors for assessing the commercial potential. The practical implications of this study primarily involve the solar energy sector, yet deemed to be of value to all potential stakeholders within the ecosystem of AV. Limitations & future research - The limitations of this study includes the potential exclusion of stakeholders within the data collection process due to the complex stakeholder configuration of AV, as well as the geographical constraints limiting this study to the context of Sweden. Future research is encouraged within several fields of this novel research area, predominantly including stakeholder involvement, business model configuration and how to mobilize the synergy sought in technology development between the solar energy- and agricultural sector.
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Design and development of a graphical user interface for the monitoring process of an automated guided vehicle fleetPaul, Johanna January 2020 (has links)
Many different autonomously driving mobile robots are used for industrial transports of materials or oods in the context of internal logistic processes because of different use cases. The problem for the users that need to monitor the robots is that each manufacturer provides its own graphical user interface (GUI) wi th different operating modes and visual designs, which requires different trainings and constant swi tching between software. Therefore, this paper shows the design and development process of a graphical user interface in the form of a web application for the monitoring process of a fleet of automated guided vehicles from different manufacturers and answers the following question: "What are the main criteria when designing a graphical user interface with high usability for the monitoring process of manufacturer-independent automa ted guided vehicle f leets?” To answer the question, existing graphical user interfaces from different manufacturers were analyzed and interviews with developers and end-users of the GUIs were conducted. Requirements were then derived, on whose basis sketching, wireframing and high-fidelity prototyping have been performed. Usability testing and a heuristic evaluation were chosen to improve the application and its usability continually. As a result, the following six main criteria could be derived that summarize the most essential points to consider when designing such a GUI: administrabi lity, adaptiveness, observability, analyzability, robot and job awareness, and intervention. / Många olika autonomt körande mobila robotar används för industriell transport av material eller varor i samband med interna logistiska processer till följd av olika användningsfall. Problemet för de användare som behöver övervaka robotarna är att varje tillverkare tillhandahåller sitt eget grafiska användargränssnitt (GUI) med olika driftsätt och visuella utformningar, vilket kräver olika utbildningar och ständig växling mellan mjukvara. Denna uppsats visar därför design- och utvecklingsprocessen för ett grafiskt användargränssnitt i form av en webbapplikation för övervakningsprocessen för en samling av automatiserade guidade fordon från olika tillverkare, och svarar på följande fråga: "Vilka är de viktigaste kriterierna vid utformningen av ett grafiskt användargränssnitt med hög användbarhet för övervakningsprocessen av automatiserade guidade fordonsamlingar, oboeroande av tillverkare?” För att svara på frågan analyserades befintliga grafiska användargränssnitt från olika tillverkare, samt intervjuer med utvecklare och slutanvändare av GUI:erna utfördes. Krav härleddes sedan, baserat på vilka skisser, wireframing och hifi -prototyper som har utförts. Användbarhetstest och en heuristisk utvärdering valdes för att kontinuerligt förbättra applikationen och dess användbarhet. Som ett resultat kan följande sex huvudkriterier härledas, de sammanfattar de viktigaste punkterna att tänka på när man utformar ett sådant GUI: förmåga att administrera, anpassningsförmåga, observerbarhet, analyserbarhet, robot- och jobbmedvetenhet och intervention.
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Thermodynamic based modelling of biohydrogen production by anaerobic fermentation / Modélisation de la digestion anaérobie par une approche basée sur la thermodynamiqueBastidas Oyanedel, Juan-Rodrigo 24 February 2011 (has links)
Ce travail de thèse a eu pour objectif principal l'étude thermodynamique des changements métaboliques dans l'acidogénèse. L'acidogénèse est un procédé anaérobie à double intérêt qui en traitant des résidus organiques, permet de produire des composés chimiques comme l'hydrogène, l'éthanol et les acides organiques. Par conséquent, l'acidogénèse se place comme un procédé biotechnologique dans le concept de bioraffinerie. En outre, ce processus n'a pas besoin de conditions stériles d'opération et fonctionne sur une large gamme de pH. Ces changements métaboliques sont dépendants des modifications dans les conditions opératoires. Afin d'étudier ces changements métaboliques, des expériences basées sur des modifications du ciel gazeux du réacteur par introduction d'azote et sur des changements du pH, ont été menées. Un des résultats les plus intéressants a été l'augmentation du rendement de production d'hydrogène de 1 à 3,2 molH2/molglucose à pH 4,5 et débit de N2 de 58,4 L/d. Ce rendement est proche de la valeur théorique (4 molH2/molglucose). L'étude thermodynamique a permis d'expliquer les mécanismes métaboliques concernant l'hydrogène, dont la production importante, représentée par le rendement de 3,2 molH2/molglucose, est due à la réaction inverse H2/NAD+, qui est thermodynamiquement faisable à faibles pressions partielles d'hydrogène (par exemple 0,02 bar). En outre, les bas rendements en hydrogène ont été expliqués par l'action consommatrice d'hydrogène par la réaction d'homoacetogénèse. Cependant, le modèle n'a pas été capable d'expliquer les changements métaboliques de l'acétate, du butyrate et de l'éthanol lors de la fermentation acidogénique du glucose. / This thesis deals with thermodynamic based modelling of metabolic shifts during acidogenic fermentation. Acidogenic fermentation is an anaerobic process of double purpose: while treating organic residues, it produces chemical compounds, such as hydrogen, ethanol and organic acids. Therefore, acidogenic fermentation arises as an attractive biotechnology process towards the biorefinery concept. Moreover, this process does not need sterile operating conditions and works under a wide range of pH.Changes of operating conditions produce metabolic shifts, inducing variability on acidogenic product yields. In order to study these metabolic shifts, an experiment design was based on reactor headspace N2-flushing (gas phase) and pH step changes (liquid phase). A major result was the hydrogen yield increase from 1 to 3.2 (molH2/molglucose) at pH 4.5 and N2-flushing of 58.4 L/d. This yield is close to the theoretical acidogenic value (4 molH2/molglucose).The thermodynamic model, based on the assumption that acidogenic fermentation is characterised by limited energy available for biological process, allowed to explain the mechanisms that govern hydrogen metabolic shifts, showing that the synthesis of extra hydrogen, i.e. yield of 3.2 (molH2/molglucose), was due to reverse H2/NAD+ redox reaction, which is thermodynamically feasible at low hydrogen partial pressures (e.g. 0.02 bar). Moreover, low hydrogen yields were explained by the action of homoacetogenesis hydrogen consuming reaction. However, the model was not capable to explain the metabolic shifts of acetate, butyrate and ethanol on acidogenic glucose fermentation.
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