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Tratamento de esgoto sanitário utilizando reatores anaeróbios operados em bateladas sequenciais (escala piloto)
Sarti, Arnaldo;Sakamoto, Isabel Kimiko;Varesche, Maria Bernadete Amancio;Zaiat, Marcelo;Foresti, Eugenio;
Engenharia Sanitaria e Ambiental , 2006, DOI: 10.1590/S1413-41522006000100010
Abstract: the performances of two anaerobic sequencing batch reactors (1.2 m3) containing biomass immobilized in inert support and as granular sludge in the treatment of domestic sewage from the campus of s?o carlos-university of s?o paulo were evaluated. the experimental phase lasted seventy days. during this period, the reactors presented quite similar performances in respect to cod and total suspended solids removal, achieving average efficiencies of approximately 60% and 75%, respectively. the analysis using molecular biology techniques on biomass samples taken at 35th and 70th showed differences in the bacterial community in the reactors indicating that the type of biomass immobilization selected the populations differently. a higher similarity was found for the archaea domain probably because these microorganisms utilize specific substrates formed at the end of the anaerobic process.
Remo??o biológica de fósforo em reatores em bateladas sequenciais com diferentes tempos de reten??o de sólidos
Henrique, Israel Nunes;Sousa, José Tavares de;Ceballos, Beatriz Susana Ovruski de;Brasil, Danielle Patrício;
Engenharia Sanitaria e Ambiental , 2010, DOI: 10.1590/S1413-41522010000200012
Abstract: in recent years, there has been an increasing need to design wastewater treatment systems that are capable of removing both organic material and nutrients, notably nitrogen and phosphorus. this study evaluated biological phosphorus removal by activated sludge systems fed with domestic sewage and operating as sequencing batch reactors (sbr) with different solids retention times (srt) namely 20, 5 and 3 days. this was supported by respirometry experiments at bench scale using acetate as the source of organic carbon. the results showed satisfactory total phosphorus removal efficiencies mean values between 79-82% for the three regimes with the best removal efficiency occurring in the sbr operating with a five-day srt.
Remo??o de sulfato de águas residuárias industriais em reator anaeróbio de leito fixo operado em bateladas sequenciais
Sarti, Arnaldo;Silva, Ariovaldo José da;C?rtes, Roberto Sarti;Foresti, Eugenio;
Engenharia Sanitaria e Ambiental , 2008, DOI: 10.1590/S1413-41522008000100003
Abstract: the potential use of an anaerobic sequencing batch biofilm reactor (asbbr) in pilot-scale for the treatment of a sulfate-rich industrial wastewater was evaluated. the pilot 1.2 m3 asbbr reactor was filled with mineral coal for biomass immobilization (fixed film). the sulfate loading rates applied were 0.15; 0.30; 0.65; 1.30 and 1.90 kg so4-2/cycle (or batch). each cycle lasted 48 h. the influent concentrations were, respectively, 0.25; 0.50; 1.0; 2.0 and 3.0 gso4-2.l-1. ethanol was used as electron donor for sulfate reduction. the reactor operated at ambient temperature (29±8oc), and the mean efficiencies of sulfate removal were in the range 88 to 92% in the 92 run cycles. the total operating period comprised 275 days. based on the results obtained in this research, it could be concluded that the asbbr can be an efficient alternative for the removal of sulfate from other industrial wastewaters with similar characteristics.
Sele o de variáveis para classifica o de bateladas produtivas com base em múltiplos critérios A multiple criteria-based method for variable selection in industrial applications  [cached]
Michel José Anzanello
Produ??o , 2013,
Abstract: Processos industriais s o frequentemente descritos por um elevado número de variáveis correlacionadas e ruidosas. Este artigo apresenta um método para sele o das variáveis mais relevantes para classifica o de bateladas de produ o valendo-se de múltiplos critérios de desempenho (sensibilidade e especificidade). As bateladas s o categorizadas em duas classes (conforme ou n o conforme, por exemplo). O método utiliza a regress o PLS (Partial Least Squares) para derivar um índice de importancia das variáveis de processo. Um procedimento iterativo de classifica o das bateladas e elimina o das variáveis é ent o conduzido. Por fim, uma medida de distancia euclidiana ponderada é aplicada para selecionar o melhor subconjunto de variáveis. Ao ser aplicado em dados de processos industriais, o método proposto reteve, em média, 12% das variáveis originais, elevando a sensibilidade em 9%, de 0,78 para 0,85, e a especificidade em 20%, de 0,64 para 0,77. Estudos de simula o permitiram avaliar o desempenho do método frente a cenários distintos. Several correlated and noisy variable are collected from industrial processes. This paper proposes a method for selecting the most relevant process variables aimed at classifying production batches into classes based on multiple criteria (e.g., sensibility and specificity). Production batches are inserted into two classes. The method first applies the PLS regression (Partial Least Squares) on process data and derives a variable importance index. A classification/elimination procedure is then carried out, and a weighted Euclidian distance is generated to identify the recommended variable subset. When applied to the testing set of real industrial data, the proposed method retained average 12% of original variables. The recommended subsets yielded 9% higher sensibility, from 0.78 to 0.85, and 20% higher specificity, from 0.64 to 0.77. Simulation experiments are also performed.
Remo??o de corante por uso de Aspergillus niger AN400 em reator em bateladas sequenciais
Rodrigues, Kelly;Silva, Karla Mayara Lima da;Silva, Glória Maria Marinho;Lima, Paulo Cesar Cunha;Wanderley, Carlos Ronald Pessoa;Silva, Germana Marinho;
Química Nova , 2011, DOI: 10.1590/S0100-40422011000700003
Abstract: a sequential batch reactor (4 l) inoculated with aspergillus niger was operated in order to remove congo red dye (10 mg l-1). the feeding of the reactor was done to each 7 days. the glucose was added in the concentration of 1 g.l-1 (stage i) and 0.5 g l-1 (stage ii). the stage iii occurred without glucose addition. the stage i was great to process, because the system reached the greater dye removal (95%) as well as the kinetic parameters ware the best - km (0.7 g l-1) and k1 (0.025 h-1).
Tratamento de água com hidrocarbonetos aromáticos por uso de reator em bateladas sequenciais com inoculo fúngico
Rodrigues, Kelly;Oliveira, Patrícia Celestino Carvalho de;Amaral Júnior, Francisco Wilame;Siqueira, Jo?o Paulo da Silva;Araújo, Rinaldo dos Santos;Wanderley, Carlos Ronald Pessoa;Marinho, Glória;
Engenharia Sanitaria e Ambiental , 2012, DOI: 10.1590/S1413-41522012000200005
Abstract: a batch reactor with air and immobilized biomass of aspergillus niger an400 was operated during 10 cycles of 7 days to remove benzene (200 mg.l-1), toluene (200 mg.l-1), and xylene (50 mg.l-1) - btx - and nutrients from basal medium. the reactor was weekly fed with 4 l of the medium and glucose - 1 g.l-1 (phase i) and 0.5 g.l-1 (phase ii). the btx had been detected until the fourth day of operation in all cycles. the best efficiencies of removal had been in phase i: 75% of soluble organic matter, 80% of orthophosphate and 77% of ammonia. the reactor can be a viable alternative for the contaminated water treatment with btx. however it has the necessity to study behavior of the reactor during longer period of operation and with shorter reaction cycles, as well as the identification of the produced metabolites.
Tratamento de esgoto sanitário em reator híbrido em bateladas sequenciais: eficiência e estabilidade na remo??o de matéria organica e nutrientes (N, P)
Lamego Neto, Luiz Gonzaga;Costa, Rejane Helena Ribeiro da;
Engenharia Sanitaria e Ambiental , 2011, DOI: 10.1590/S1413-41522011000400013
Abstract: this paper presents the results about the behavior of a sequencing batch hybrid reactor on combined removal of carbonaceous matter, nitrogen and phosphorus from sewage. operated in 8-hour cycles, the reactor had a nylon net fixed inside. loads between 0.39 and 1.35 kg cod.m-3.day-1, 42 and 60 gn-nh4-m-3.day-1 and 51 and 70 gp-po4-m-3.day-1 were tested. the reactor operated as a stable system and showed good depuration conditions. the carbonaceous matter removal was high, with 92 and 80% efficiencies average to bod5 and cod, respectively. the nutrients removal varied between 59 and 71% for total nitrogen and between 45 and 67% for total phosphorus. in both, sludge in suspension and the biofilm, occurrence of ammonium-oxidizing bacteria and microorganisms responsible for denitrification and biological phosphorus removal was observed.
Tratamento de água com hidrocarbonetos aromáticos por uso de reator em bateladas sequenciais com inoculo fúngico Treatment of water with aromatic hydrocarbons by use of sequential batch reactor with fungi inoculum  [cached]
Kelly Rodrigues,Patrícia Celestino Carvalho de Oliveira,Francisco Wilame Amaral Júnior,Jo?o Paulo da Silva Siqueira
Engenharia Sanitaria e Ambiental , 2012,
Abstract: Um reator em batelada, aerado, com biomassa imobilizada de Aspergillus niger AN400 foi operado durante 10 ciclos de 7 dias para remover benzeno (200 mg.L-1), tolueno (200 mg.L-1) e xileno (50 mg.L-1) - BTX - e de nutrientes de meio basal. O reator era alimentado semanalmente com 4 L do meio e glicose - 1 g.L-1, na Fase I, e 0,5 g.L-1, na Fase II. Os BTX foram detectados até o quarto dia de opera o, em todos os ciclos. As melhores eficiências médias de remo o foram na Fase I: 75%de matéria organica solúvel, 80% de ortofosfato e 77% de am nia. O reator pode ser uma alternativa viável para tratamento de águas poluídas com BTX, porém há a necessidade de estudar o comportamento do reator durante período de opera o mais longo e com ciclos reacionais mais curtos, bem como da identifica o dos metabólitos produzidos. A batch reactor with air and immobilized biomass of Aspergillus niger AN400 was operated during 10 cycles of 7 days to remove benzene (200 mg.L-1), toluene (200 mg.L-1), and xylene (50 mg.L-1) - BTX - and nutrients from basal medium. The reactor was weekly fed with 4 L of the medium and glucose - 1 g.L-1 (Phase I) and 0.5 g.L-1 (Phase II). The BTX had been detected until the fourth day of operation in all cycles. The best efficiencies of removal had been in Phase I: 75% of soluble organic matter, 80% of orthophosphate and 77% of ammonia. The reactor can be a viable alternative for the contaminated water treatment with BTX. However it has the necessity to study behavior of the reactor during longer period of operation and with shorter reaction cycles, as well as the identification of the produced metabolites.
Proposta de um método racional para o dimensionamento de reatores de tratamento de esgotos por lodos ativados em bateladas para remo??o de carga organica
Santos, Rafael Carvalho de Oliveira;Barbosa Filho, Olavo;Giordano, Gandhi;
Engenharia Sanitaria e Ambiental , 2006, DOI: 10.1590/S1413-41522006000200008
Abstract: this paper presents a methodology for the rational sizing of batch operating activated sludge sewage treatment biological reactors for bod removal. developed calculation method computes all the parameters simultaneously involved in the process, modeling the interaction (due to the alternate use of one single tank both as a biological reactor and as a final settling tank) among the factors that determine the treatment unit performance. this work includes a brief review of the literature concerning the subject of the present study, followed by the derivation of the proposed mathematical model, a suggested sizing procedure and an application of the worked out method.
Gráficos de controle multivariados para monitoramento de processos n o lineares em bateladas Multivariate control charts for monitoring non-linear batch processes  [cached]
Danilo Marcondes Filho,Flávio Sanson Fogliatto,Luiz Paulo Luna de Oliveira
Produ??o , 2011,
Abstract: Processos industriais em bateladas s o empregados com frequência na produ o de certos itens. Tais processos disponibilizam uma estrutura de dados peculiar; diante disso, existe um crescente interesse no desenvolvimento de gráficos de controle multivariados mais apropriados para seu monitoramento. Investiga-se aqui uma abordagem recente que utiliza gráficos de controle baseados no método Statis. O Statis constitui-se em uma técnica exploratória que permite avaliar similaridade entre matrizes de dados. Entretanto, essa técnica considera a similaridade em um contexto linear, investigando estruturas de correla o lineares nos dados. Prop e-se neste artigo a utiliza o de gráficos de controle baseados no Statis em conjunto com kernels para monitoramento de processos com presen a de n o linearidades fortes. Através dos kernels, definem-se fun es n o lineares dos dados para melhor representa o da estrutura a ser caracterizada pelo método Statis. Essa nova abordagem, denominada kernel-Statis, é desenvolvida e avaliada utilizando dados de um processo simulado. Industrial batch processes are widely used in the production of certain items. Such processes provide a peculiar data structure; therefore there is a growing interest in the development of customized multivariate control charts for their monitoring. We investigate a recent approach that uses control charts based on the Statis method. Statis is an exploratory technique for measuring similarities between data matrices. However, the technique only assesses similarities in a linear context, i.e. investigating structures of linear correlation in the data. In this paper we propose control charts based on the Statis method in conjunction with a kernel for monitoring processes in the presence of strong nonlinearities. Through kernels we define nonlinear functions of data for better representing the structure to be characterized by the Statis method. The new approach, named kernel-Statis, is developed and illustrated using simulated data.
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