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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
201

Ochre and biochar : technologies for phosphorus capture and re-use

Shepherd, Jessica Grace January 2017 (has links)
Despite recent instability in the global supply of phosphate-rock derived fertiliser and the potential for this to continue into the future, the recovery of phosphorus (P) from wastewater treatment systems, where P is abundant and accessible, is well below maximum potential. Considerable resource is spent on removing P from wastewater in order to comply with environmental standards and to protect aquatic ecosystems from eutrophication, yet there is little emphasis on capturing the P in a way that is optimised for re-using it as agricultural fertiliser. To address this lack of innovation in the face of climate change and food insecurity, a concept for a material capable of capturing P from wastewater was developed, with an emphasis on the utilisation of otherwise waste materials and the use of carbon neutral or negative production technologies. Based on the demonstrated P capture properties of coal minewater treatment waste (ochre) and biochar made from anaerobically digested feedstocks, a range of biochars were designed and produced using different mixtures of ochre (“OC”), sourced from the UK Coal Authority Minto minewater treatment scheme in Fife, Scotland and anaerobically digested sewage sludge (“AD”), sourced from the Newbridge wastewater treatment plant in Edinburgh. A first generation of materials consisting of either AD or a 1:1 mixture (dry weight basis) of OC and AD were produced in a small-scale batch pyrolysis unit at two pyrolysis highest treatment temperatures (HTTs) (450 and 550°C) to give the biochars AD450, AD550, OCAD450 and OCAD550. These were tested for their P capture properties in repeated P-exposure experiments with pH buffering in comparison to unpyrolysed ochre, activated carbon and a natural zeolite. After 5 days of repeated exposure to a P solution at a wastewater-relevant concentration (20 mg P l-1) replenished every 24 h, relatively high masses of P were recovered by ochre (1.73 ± 8.93×10-3 mg P g-1) and the biochars OCAD550 (1.26 ± 4.66×10-3 mg P g-1), OCAD450 (1.24 ± 2.10×10-3 mg P g-1), AD450 (1.06 ± 3.84×10-3 mg P g-1), and AD550 (0.986 ± 9.31×10-3 mg P g-1). The biochar materials had higher removal rates than both activated carbon (0.884 ± 1.69×10-2 mg P g-1) and zeolite (0.130 ± 1.05×10-2 mg P g-1). To assess the extractability of recovered P and thus potential plant bioavailability, P exposure was followed by repeated extraction of the materials for 4 days with pH 7-buffered deionised water. The AD biochars retained 55% of the P recovered, OCAD biochars 78% and ochre 100%. Assessment of potentially toxic element (PTE) concentrations in the biochars against guideline values indicated low risk associated with their use in the environment. A second generation of materials were produced to examine the scalability of the concept. Mixtures of AD and OC were pelletised with a lignin binder (89.1:9.9:1.0 ratio, dry weight basis) and AD was pelletised with binder (99:1 ratio, dry weight basis). The pelletised feedstocks were pyrolysed in a bench-scale continuous flow pyrolysis kiln at the same two HTTs to give the pelletised biochars PAD450, PAD550, POCAD450 and POCAD550. Analysis of digested biochar samples compared to the previous generation of biochars showed general similarities between the two groups, apart from the substantially lower Fe content. Sub-samples of the pelletised biochars were exposed to a 20 mg l-1 P solution over 6 days, with the solution replaced every 24 h to give the P-exposed biochars EPAD450, EPAD550, EPOCAD450 and EPOCAD550. To probe the mechanisms of P capture by these materials and how feedstock preparation and pyrolysis conditions affected these, spectroscopic analysis using laser-ablation (LA) ICP-MS, X-ray diffraction, X-ray photo-electron spectroscopy (XPS) and scanning electron microscopy coupled with energy dispersive X-ray was performed. The results highlighted the general importance of Fe minerals in P capture and subsidiary roles for Al, Ca and Si. A 3-week barley (Hordeum vulgare) seedling growth experiment was conducted using the pelletised and P-exposed biochars, in comparison with other biochars produced using feedstock which contained high amounts of PTEs. The biochars were also extracted using a range of different methods used to assess the bioavailability of PTEs and nutrients in soils, and the results compared to digests of barley leaves to identify whether any of these could reliably predict plant bioavailability in biochar. The above ground biomass and its total P concentration of barley grown in a 5% mixture of EPOCAD550 in sand was significantly higher than the control (p < 0.05 and p < 0.01, respectively). A significant positive correlation between mean leaf P mass and dry weight leaf yield (R2 = 0.865, p < 0.001) was found, indicating that dry weight yield could be used as an indicator for the P fertilising capability of biochar for barley seedlings. Element concentrations in unbuffered and buffered and (pH 7) 0.01 M CaCl2 biochar extractions were significantly positively correlated with plant leaf concentration for 6 of the 18 elements investigated, more than any of the other extractions. A longer barley growth experiment was conducted, using rhizoboxes, to test the bioavailability of P in the biochars compared to conventional fertiliser. The pelletised and Pexposed biochars were applied to a sandy loam soil with P constraints. Biochar application rates were based on 2% formic acid extractable P, calculated for summer barley using Index 0 soil. Analysis of total leaf length at harvest (12 weeks), dry weight yield, leaf P concentration and leaf P mass showed no significant differences between the biochar treatments, NPK fertilised and NK fertilised controls. This shows that biochar, when applied at low total application rates based on extractable P, is as effective as conventional fertiliser. Now that AD biochar materials have been shown to have useful phosphorus recycling properties in laboratory experiments, additional work is required to optimise their use in wastewater and agricultural systems. The next stage of research should determine their performance in flow-through filtration systems with simulated and real wastewater effluent, as well as their performance in field trials with different crops of interest to demonstrate their potential as viable alternative fertilisers.
202

Operational water quality management : control of stormwater discharges

Lessard, Paul January 1989 (has links)
No description available.
203

A comparison of two single-vessel reactor types for the treatment of textile wastes

Shaw, Christopher B. January 2000 (has links)
The feasibility of using a single vessel reactor for the biological treatment of recalcitrant compounds, namely reactive azo dyes discharged by the textile finishing industry was investigated. A synthetic effluent was derived from real processes to give reproducibility throughout the experimental period. The literature review found that a sequenced treatment of anaerobic then aerobic redox environments was required for the decolourisation and mineralisation of the dyes. Two biological reactor types were accordingly designed, built and tested, the sequencing batch reactor (SBR) and the hybrid anaerobic baffled reactor (HABR).
204

Avaliação da vazão do microaspersor Amanco MF, antes e após o uso com água residuária

Oliveira, Erika Fabiana de [UNESP] 14 November 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:46Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-11-14Bitstream added on 2014-06-13T20:55:19Z : No. of bitstreams: 1 oliveira_ef_me_botfca.pdf: 373580 bytes, checksum: 7894815e03cdcc2c621d7434458eca47 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Universidade Estadual Paulista (UNESP) / O presente trabalho foi realizado no Laboratório de Ensaio de Equipamentos de Irrigação do Departamento de Engenharia Rural da Universidade Estadual Paulista FCA- UNESP de Botucatu – SP, teve como objetivo avaliar a vazão do microaspersor Amanco MF Bocal verde claro 1,0mm, com vazão nominal de 43L h-1, antes e após o uso com água residuária, com ensaios em bancada. Na primeira fase da pesquisa 25 emissores novos foram separados aleatoriamente e realizados dois tipos de ensaios com água limpa, um com coleta dos dados dos emissores dispersos sobre a bancada e outro com a coleta de dados dos emissores situados em um único ponto da mesma, com intuito de observar qual a metodologia obteria melhores resultados, as pressões de ensaio foram 50, 100, 150, 200, 250 e 300 kPa . Numa segunda fase os emissores foram submetidos a 1000h operando com água de reúso. Ao término desse tempo, novamente foram submetidos às condições de ensaio inicial, para avaliar o desempenho do microaspersor, antes e depois de trabalhar com água de reúso, o parâmetro estudado foi a vazão média, para depois se calcular o desvio padrão, coeficiente de variação e curva vazão versus pressão. Ao final pode-se observar que o microaspersor Amanco MF bocal verde claro, obteve um melhor desempenho no ensaio realizado em um único ponto da bancada, ou seja, sob as mesmas variáveis e condições e que o uso da água residuária pouco influenciou nodesempenho dos emissores, pois a vazão média dos emissores depois de usado diminuiu em relação a vazão dos emissores antes do uso em 6,59%, o coeficiente de variação após o uso ficou em 5,115 %, aumentado em relação ao coeficiente de fabricação inicial que foi de 4,325%, o R² teve uma queda, passando de 0,9946 para 0,9898, mas o microaspersor continuou com uma boa classificação, de acordo com as normas da ABNT e ASAE. / This work was done in the Laboratory of Irrigations Equipments Tests of the de Departamento de Engenharia Rural of the Universidade Estadual Paulista FCAUNESP of Botucatu - SP, aimed to assess the flow of microsprinkler Amanco MF Mouthpiece light green 1.0 mm, with nominal flow rate of 43 l h-1, before and after use with wastewater, with tests on bench. In the first phase of the survey 25 new emitters were separate at random and made two types of tests with clean water, with a collection of data from transmitters scattered on the bench and another with the collection of data from transmitters located in a single point of the same, with order to see what the methodology obtain better results, the pressures of testing were 50, 100, 150, 200, 250 and 300 kPa.In a second stage, the emitters have been submitted to 1000h operating with water reuse. At the end of those hours, were again subject to the conditions of initial testing, to assess the performance of microsprinkler, before and after working with water for reuse, the parameter were studied flow average, and then to calculate the standard deviation, coefficient of variation curve and flow versus pressure. At the end data show that the microsprinkler Amanco MF mouthpiece light green, got a better performance in the test conducted in a single point on the bench, or under the same conditions and variables and that the use of wastewater little influence in performance of emitters, as the average flow of transmitters used after declined for a new 6,59%, the coefficient of variation after use was 5,115%, increased in proportion to the coefficient of manufacturing which was 4,325%, the R ² had a fall from 0,9946 to 0,9898, and microsprinklers continued with a good rating, according to the rules of ABNT and ASAE.
205

Biodigestão anaeróbia dos dejetos de suínos e bovinos e utilização do biofertilizante no capim-piatã

Orrico Junior, Marco Antonio Previdelli [UNESP] 16 November 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:49Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-11-16Bitstream added on 2014-06-13T18:44:18Z : No. of bitstreams: 1 orricojunior_map_dr_jabo.pdf: 482614 bytes, checksum: b08501b61ead8cdeb8c686e30852c8ce (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O objetivo do trabalho foi identificar as alterações na composição e no processo de biodigestão dos dejetos gerados por suínos e bovinos de corte na fase de terminação, alimentados com diferentes dietas e submetidos a distintos tempos de retenção hidráulica (TRH), e ainda, verificar a influência dos tipos e doses dos biofertilizantes sobre as características produtivas, morfogênicas, estruturais e valor nutritivo do capim Piatã. Para cada espécie animal foram adotadas duas dietas diferentes, sendo que para os suínos uma das dietas conteve milho e a outra sorgo, como recurso energético, e para os bovinos as dietas variaram as proporções entre volumoso (V) e concentrado (C) (40V:60C e 60V:40C). O ensaio de caracterização dos dejetos nas condições descritas foi realizado anteriormente ao processo de biodigestão anaeróbia, para o qual foram adotados TRH de 30, 60, 90 e 120 dias, em reatores batelada. Com base nos teores de N adotaram-se diferentes doses (0, 100, 200 e 300 kg.ha-1 equivalente N) dos biofertilizantes (bovino e suíno) para a produção de capim Piatã. Os resultados demonstraram que o aumento da proporção de V na dieta dos bovinos e o uso de sorgo na dieta de suínos resultaram em menor eficiência dos potenciais de produção de biogás e metano, que foram em média 13,0 e 8,6% menor, respectivamente. Não foram observadas diferenças significativas sob a produção de forragem e parâmetros avaliados para os dois biofertilizantes, no entanto, verificou-se melhora das características produtivas, morfogênicas, estruturais e do valor nutritivo da forrageira, seguindo modelos lineares de predição, em relação às doses de N empregadas na adubação / The aim of this work was to identify the alterations on compound and biodigestion process of waste from ending swine and beef cattle that were fed with different diets and submitted to distinct hydraulic retention times (HRT), and also to verify the influence of types and doses of biofertilizers on productive, morphogenic, structural characteristics and nutrient value of Piatã pasture. For every animal species, two different diets were adopted, which one had corn and other had sorgum, for swine, as energy source, and for cattle, diets varied between roughage (R) and concentrate (C) (40R:60C and 60R:40C). Waste characterization trial in described conditions was done before anaerobic biodigestion process, for that HTR of 30, 60, 90 and 120 days were adopted, in batch reactor. Based on contents of N, different doses were adopted (0, 100, 200 and 300 kg ha-1, N equivalent) of biofertilizers (cattle and swine) for Piatã pasture yield. Results showed that the increasing of roughage proportion in cattle diet and the use of sorghum in swine diet resulted in less efficiency of biogas and methane production potential, which were in average 13.0 and 8.6 % smaller, respectively. It were not observed significative differences under pasture yield and evaluated parameters for both two biofertilizers, however, an improvement of productive morphogenic, structural characteristics and nutrient value of pasture was verified, following prediction linear models, in relation to doses of N using for fertilization
206

Applications of membrane aerated biofilm reactors for wastewater treatment

Murray, Simon Thomas January 2016 (has links)
Despite being the subject of peer reviewed research since the mid-1980s, the conservative nature of the wastewater treatment industry means that the commercial application of membrane aerated biofilm reactors has not realized the potential that the published research demonstrates. The early research demonstrated the ability of membrane aerated biofilm reactors to achieve good levels of pollutant removal from various types of wastewater, but also exposed several weaknesses of the technology (i.e. cost of membranes, control of biofilm thickness) which have prevented the concept of MABfRs being developed in viable wastewater treatment technologies. However, as membrane technology has developed, the cost of suitable membranes has fallen, prompting the research community to revisit the concept. This later batch of research has identified several niche applications where membrane supported biofilms can be used for effective removal of pollutants from water. Using the MABfR for the treatment of secondary effluent as a polishing step is another niche application which has been identified and is examined in this work; leading to the development of a patented treatment technology – the BioSettler.
207

Sistema de tratamento anaeróbio, aeróbio e anóxico para águas residuárias de suinocultura: remoção de matéria orgânica, de nutrientes e de coliformes

Santos, Samantha Christine [UNESP] 21 February 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-21Bitstream added on 2014-06-13T18:56:05Z : No. of bitstreams: 1 santos_sc_me_jabo.pdf: 2783682 bytes, checksum: aa4f46c105293436eec8cc85842f4187 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Neste estudo avaliou-se o desempenho de processo anaeróbio, aeróbio e anóxico, utilizando-se um reator anaeróbio compartimentado (ABR de 360 L), com duas câmaras, um filtro aerado submerso (FAS de 160 L), preenchido com anéis de bambu e anéis de plástico de eletroduto corrugado e um reator de fluxo ascendente com manta de lodo (USB de 120 L) anóxico, instalados em série, para o tratamento de águas residuárias de suinocultura, com concentrações médias de sólidos suspensos totais (SST) de 10708 a 17048 mg L-1. Os tempos de detenção hidráulica (TDH) foram de 24 e 12 h no reator ABR; de 7,9 e 3,9 h e de 9,1 e 4,5 h no FAS preenchido com anéis de bambu e anéis de plástico de eletroduto corrugado, respectivamente; e de 7,8 e 3,9 h no reator USB anóxico. O FAS foi submetido a condições de aeração intermitente e contínua. As eficiências médias de remoção de DQOtotal foram de 94 a 99% no sistema de tratamento anaeróbio, aeróbio e anóxico, com carga orgânica volumétrica (COV) de 35,9 a 93,0 g DQOtotal (L d)-1 no reator ABR. As maiores eficiências médias de remoção foram de 99,99; 98; 99; 91; 88; 99 e 94% para os coliformes termotolerantes, DQOdiss, SST, NT, P-total, Cu e Zn, respectivamente, no sistema de tratamento anaeróbio, aeróbio e anóxico, obtendo-se valores mínimos de 1,1 x 103 NMP/100 mL para coliformes termotolerantes e 221 mg L-1 para DQOtotal. A porcentagem de CH4 no biogás do ABR variou de 76 a 84%; de N2 no reator USB anóxico chegou a 74%, com COV de 13,1 g DQOtotal (L d)-1 e TDH de 4 h. Os valores da atividade específica da microbiota do lodo das câmaras do ABR apresentaram diferenças, evidenciado a habilidade de separação das fases hidrolítica, acidogênica e metanogênica. A caracterização morfológica do biofilme do FAS, por meio de microscopia óptica, indicou alta diversidade morfológica, a qual pode estar associada a sistemas de tratamento biológico estáveis / In this study it was evaluated the performance of the anaerobic, aerobic and anoxic process in an anaerobic baffled reactor (ABR of 360 L), with two chambers, a submerged aerated filter (SAF of 160 L), filled with bamboo rings and plastic rings, and an anoxic upflow sludge blanket reactor (USB of 120 L), installed in series, for swine wastewater treatment, with mean total suspended solid (TSS) concentration from 10708 to 17048 mg L-1. The hydraulic detention times (HDT) were 24 and 12 h in the ABR reactor; 7,9 e 3,9 h and 9,1 e 4,5 h in the SAF filled with bamboo rings and plastic rings, respectively; 7,8 and 3,9 h in the anoxic USB reactor. Conditions of intermittent and continuous aeration were applied at the SAF. The mean of CODtotal removal efficiencies ranged from 94 to 99% in the anaerobic, aerobic and anoxic treatment system under organic loading rate (OLR) of 35,9 to 93,0 g total COD (L d)-1 in the ABR reactor. The highest mean removal efficiencies were of 99,99; 98; 99; 91; 88; 99 e 94% for thermotolerant coliforms, dissCOD, TSS, TN, total-P, Cu and Zn, respectively, in the anaerobic, aerobic and anoxic treatment system, obtaining minimum values of 1,1 x 103 MPN/100 mL for thermotolerant coliforms and 221 mg L-1 for CODtotal. The CH4 percentage in the biogas ABR ranged from 76 to 84%; the N2 percentage in the anoxic USB reactor reached 74%, with COV of 13,1 g total COD (L d) -1 and HDT of 4 h. The observed values of microbial specific activity of the sludge in the ABR‟s chambers were significantly different, evidenced the ability to phase separation hydrolytic, acidogenic and methanogenic. The SAF biofilm morphology, through optical microscopy, indicated a high morphological diversity, which may be associated with stable biological treatment systems
208

Tratamento de manipueira de fecularia em biodigestor anaeróbio para disposição em corpo receptor, rede pública ou uso em fertirrigação

Pinto, Paulo Henrique Mendonça [UNESP] 06 August 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:24:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-08-06Bitstream added on 2014-06-13T20:12:53Z : No. of bitstreams: 1 pinto_phm_me_botfca.pdf: 1393017 bytes, checksum: ba5d604cb5f1d74e2ea4e7db1accf8da (MD5) / Manipueira de extração de fécula de mandioca, em separado da água de lavagem das raízes, através de biodigestores anaeróbios de fluxo ascendente, com separação das fases, sem controle de temperatura ou adição de produtos químicos e, avaliar sua adequabilidade, através das suas características físicas e químicas para lançamento em corpo receptor, sistema público coletor de esgotos ou, aplicação em processo de fertirrigação. Depois dos reatores estabilizados, foram realizados ensaios variando a vazão de alimentação com 8,0; 12,0 e 16,0 Ld-1, correspondentes a um tempo de retenção hidráulica de 8,17; 5,44 e 4,08 dias respectivamente. Os melhores resultados para redução da carga orgânica foram obtidos com os tempos de retenção hidráulica (TRH) de 8,17 e 5,44 dias com eficiências médias de 89,8 e 80,9% respectivamente. As características físicas e químicas dos efluentes tratados foram comparadas com os valores estabelecidos na legislação estadual, federal e, com os parâmetros utilizados pelo órgão ambiental fiscalizador. Os resultados obtidos mostraram que o efluente tratado atende parcialmente aos requisitos legais para o lançamento em corpos receptores, devido ao teor elevado de nitrogênio amoniacal. Por outro lado, foram atendidos integralmente os requisitos legais para o lançamento na rede pública coletora de esgotos. O efluente tratado não atendeu às recomendações requeridas pelo órgão ambiental fiscalizador para a sua disposição através de processo de fertirrigação devido aos teores elevados de ferro (Fe++) e de fluoretos (F-). Considerando os resultados obtidos, concluímos que, devido à simplicidade do sistema utilizado, com a implantação de melhorias como um pós tratamento, poderiam ser atingidos os parâmetros que atenderiam integralmente a legislação. / The aim of this paper was to evaluate the efficiency of the treatment of cassava wastewater, separately from the root washing water, by means of ascending flux anaerobic biodigesters, with separation of the phases, without temperature control or addition of chemical products and to evaluate its suitability by means of its physical and chemical characteristics for throwing in receiving body, public sewage system or application in fertilization and irrigation. After reactors had been stabilized, essays were conducted varying feeding flow with 8.0, 12.0 and 16.0 Ld-1, corresponding to a hydraulic retention time of 8.17, 5.44 and 4.08 days, respectively. The best reduction for organic load reduction were obtained with hydraulic retention times (HRT) of 8.17 and 5.44 days with mean efficiencies of 89.8 and 90.9%, respectively. Physical and chemical characteristics of treated effluents were compared with the values established in the current state and federal legislation and with the parameters used by the environmental supervising organ. The results we obtained showed that the treated effluent partially meets the legal requirements for throwing in receiving bodies owing to high contents of ammonia nitrogen. On the other hand, legal requirements were fully met to throw effluents into the public sewage system. The treated effluent did not fulfill the recommendations required by the environmental supervising organ for its disposal by means of fertilization and irrigation due to high concentrations of iron (Fe++) and fluorides (F-). Considering the results obtained, we conclude that, due to the simplicity of the system used, as improvements such as after-treatment are made, parameters fully obeying the legislation could be met.
209

Investigation and development of methods for optimal control of the activated sludge process

Kujane, Koketso Portia January 2009 (has links)
Thesis (MTech (Electrical Engineering))--Cape Peninsula University of Technology, 2009 / This project was started as a result of strict environmental and health regulations together with a demand tor cost effective operation of wastewater treatment plants (VVWTPs). The main aim of this project is how to keep effluent concentration below a prescribed limit at the lowest possible cost. Due to large fluctuations in the quality and quantity of the influent concentrations, traditional control methods are not adequate to achieve this aim The major drawback with these methods is that the disturbances affect the process before the controller has time to correct the error (Olsson and Newell, 1999: 454). This problem is addressed through the use of modern control systems. Modern control systems are model based predictive algorithms arranged as feed-forward controllers (Olsson and Newell. 1999: 454). Normally a controller is equipped with a constant set point; the goal In this project is to calculate an optimal DO trajectory that may be sampled to provide a varying optimal set-point for the Activated Sludge Process, In this project an optimal control problem Is formulated using DO concentration as a control variable. This requires a model of the process to be controlled a mathematical expressions of the limitations on the process input and output variables and finally the objective functional. which consists of the objectives of the control. The structures of the Benchmark plant (developed within the COST 682 working group) and the Athlone WWTPs are used to implement this opt.mat control strategy in MATLAB. The plant's full models are developed based on the mass balance principle incorporating the activated sludge biological models: ,ASM1, ASM2, ASM2d and ASM3 (developed by the IWA working groups). To be able to develop a method that may later on be used for online control, the full models are reduced based on the technique In Lukasse (1996). To ensure that the reduced models keep the same prediction capabilities as the full models, parameters of the reduced models are calculated based on the Least Squares principle, The formulated optimal control problem is solved based on the decompostion-coorcdination method that involves time decomposition in a two layer structure. MATLAB software [5 developed to solve the problems for parameter estimation. fun and reduced mode! simulation. and optimal control calculation for the considered different cases of plant structures and biological models. The obtained optimal 00 trajectories produced the effluent state trajectories within prescribed requirements. These DO trajectories may be implemented in different SCADA systems to be tracked as set points or desired trajectories by different types of controllers.
210

Avaliação da vazão do microaspersor Amanco MF, antes e após o uso com água residuária /

Oliveira, Erika Fabiana de, 1981- January 2008 (has links)
Orientador: Raimundo Leite Cruz / Banca: Antonio de Pádua Sousa / Banca: Helton Rogério Mazzer / Resumo: O presente trabalho foi realizado no Laboratório de Ensaio de Equipamentos de Irrigação do Departamento de Engenharia Rural da Universidade Estadual Paulista FCA- UNESP de Botucatu - SP, teve como objetivo avaliar a vazão do microaspersor Amanco MF Bocal verde claro 1,0mm, com vazão nominal de 43L h-1, antes e após o uso com água residuária, com ensaios em bancada. Na primeira fase da pesquisa 25 emissores novos foram separados aleatoriamente e realizados dois tipos de ensaios com água limpa, um com coleta dos dados dos emissores dispersos sobre a bancada e outro com a coleta de dados dos emissores situados em um único ponto da mesma, com intuito de observar qual a metodologia obteria melhores resultados, as pressões de ensaio foram 50, 100, 150, 200, 250 e 300 kPa . Numa segunda fase os emissores foram submetidos a 1000h operando com água de reúso. Ao término desse tempo, novamente foram submetidos às condições de ensaio inicial, para avaliar o desempenho do microaspersor, antes e depois de trabalhar com água de reúso, o parâmetro estudado foi a vazão média, para depois se calcular o desvio padrão, coeficiente de variação e curva vazão versus pressão. Ao final pode-se observar que o microaspersor Amanco MF bocal verde claro, obteve um melhor desempenho no ensaio realizado em um único ponto da bancada, ou seja, sob as mesmas variáveis e condições e que o uso da água residuária pouco influenciou nodesempenho dos emissores, pois a vazão média dos emissores depois de usado diminuiu em relação a vazão dos emissores antes do uso em 6,59%, o coeficiente de variação após o uso ficou em 5,115 %, aumentado em relação ao coeficiente de fabricação inicial que foi de 4,325%, o R² teve uma queda, passando de 0,9946 para 0,9898, mas o microaspersor continuou com uma boa classificação, de acordo com as normas da ABNT e ASAE. / Abstract: This work was done in the Laboratory of Irrigations Equipments Tests of the de Departamento de Engenharia Rural of the Universidade Estadual Paulista FCAUNESP of Botucatu - SP, aimed to assess the flow of microsprinkler Amanco MF Mouthpiece light green 1.0 mm, with nominal flow rate of 43 l h-1, before and after use with wastewater, with tests on bench. In the first phase of the survey 25 new emitters were separate at random and made two types of tests with clean water, with a collection of data from transmitters scattered on the bench and another with the collection of data from transmitters located in a single point of the same, with order to see what the methodology obtain better results, the pressures of testing were 50, 100, 150, 200, 250 and 300 kPa.In a second stage, the emitters have been submitted to 1000h operating with water reuse. At the end of those hours, were again subject to the conditions of initial testing, to assess the performance of microsprinkler, before and after working with water for reuse, the parameter were studied flow average, and then to calculate the standard deviation, coefficient of variation curve and flow versus pressure. At the end data show that the microsprinkler Amanco MF mouthpiece light green, got a better performance in the test conducted in a single point on the bench, or under the same conditions and variables and that the use of wastewater little influence in performance of emitters, as the average flow of transmitters used after declined for a new 6,59%, the coefficient of variation after use was 5,115%, increased in proportion to the coefficient of manufacturing which was 4,325%, the R ² had a fall from 0,9946 to 0,9898, and microsprinklers continued with a good rating, according to the rules of ABNT and ASAE. / Mestre

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