904 resultados para effluent


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This study used a multi-analytical approach based on traditional microbiological methods for cultivation and isolation of heterotrophic bacteria in the laboratory associated with the molecular identification of the isolates and physicochemical analysis of environmental samples. The model chosen for data integration was supported by knowledge from computational neuroscience, and composed by three modules: (i) microbiological parameters, contemplating taxonomic data obtained from the partial sequencing of the 16S rRNA gene from 80 colonies of heterotrophic bacteria isolated by plating method in PCA media. For bacterial colonies isolation were used water samples from Atibaia and Jaguarí rivers collected at the site of water captation for use in effluent treatment, upstream from the entrance of treated effluent from the Paulínia refinery (REPLAN/Petrobras) located in the Paulínia-SP municipality, from the output of the biological treatment plant with stabilization pond and from the raw refinery wastewater; (ii) chemical parameters, ending measures of dissolved oxygen (DO), chemical oxygen demand (COD), biochemical oxygen demand (BOD), chloride, acidity CaCO3, alkalinity, ammonia, nitrite, nitrate, dissolved ions, sulfides, oils and greases; and (iii) physical parameters, comprising the pH determination, conductivity, temperature, transparency, settleable solids, suspended and soluble solids, volatile material, remaining fixing material (RFM), apparent color and turbidity. The results revealed interesting theoretical relationships involving two families of bacteria (Carnobacteriaceae and Aeromonadaceae). Carnobacteriaceae revealed positive theoretical relationships with COD, BOD, nitrate, chloride, temperature, conductivity and apparent color and negative theoretical relationships with the OD. Positive theoretical relationships were shown between Aeromonadaceae and OD and nitrate, while this bacterial family showed negative theoretical...

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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The contribution of wastewater from a tannery industry to the pollution of a stream was investigated. The main parameters studied were biochemical oxygen demand, chemical oxygen demand, chromium, dissolved oxygen, fecal and total conforms, nitrogen, oils and greases, pH, phosphorous, sulfides, suspended solids, turbidity, and volatile solids. Three sampling points were located: (I) at the discharge point of tannery wastewater, (2) 50 m upstream, and (3) 80 m downstream of discharge point. Also was investigated the pollution at the stream source.

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This paper presents the development of a procedure, which enables the analysis of nine pharmaceutical drugs in wastewater using gas chromatography-mass spectrometry (GC-MS) associated with solid-phase microextraction (SPME) for the sample preparation. Experimental design was applied to optimize the in situ derivatization and the SPME extraction conditions. Ethyl chloroformate (ECF) was employed as derivatizing agent and polydimethylsiloxane-divinylbenzene (PDMS-DVB) as the SPME fiber coating. A fractional factorial design was used to evaluate the main factors for the in situ derivatization and SPME extraction. Thereafter, a Doehlert matrix design was applied to find out the best experimental conditions. The method presented a linear range from 0.5 to 10 mu g/L, and the intraday and interday precision were lower than 16%. Applicability of the method was verified from real influent and effluent samples of a wastewater treatment plant, as well as from samples of an industry wastewater and a river.

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In this study, carra sawdust pre-treated with formaldehyde was used to adsorb reactive red 239 (RR239). The effects of several experimental conditions, including the concentration of dye, sorbent dosage, temperature, ionic strength, stirring speed and solution pH, on the kinetics of the adsorption process have been studied, and the experimental data were fitted to pseudo-second-order model. A study of the intra-particle diffusion model indicates that the mechanism of dye adsorption using carra sawdust is rather complex and is most likely a combination of external mass transfer and intra-particle diffusion. The experimental data obtained at equilibrium were analyzed using the Langmuir and Freundlich isotherm models, and the results indicated that at this concentration range, both models can be applied for obtaining the equilibrium parameters. The maximum dye uptake obtained at 298 K was found to be 15.1 mg g(-1). In contrast to the usual systems, the reactive dye studied in the present work is strongly attached to the sawdust even after several washes with water, allowing it to be discarded as a solid waste.

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Este trabalho teve como objetivo avaliar o tratamento de água bruta proveniente de um reservatório de água, utilizando instalação piloto de dupla filtração (DF), composta por filtro ascendente de pedregulho (FAP) e filtro rápido descendente de areia (FRD), seguida de uma unidade de pós-tratamento com carvão ativado granular (CAG). Adicionalmente, foi verificado o efeito da pré e interoxidação (entre o FAP e o FRD) na eficiência global do tratamento e na formação de subprodutos orgânicos halogenados (SOH). Em função dos resultados obtidos, foi observado que a pré-oxidação melhorou a qualidade do efluente do FAP e a interoxidação favoreceu que resultassem valores menores de turbidez e cor no efluente do FRD. O processo de tratamento por adsorção em carvão ativado granular, utilizado como pós-tratamento, mostrou-se eficiente para assegurar a qualidade dos efluentes finais nos ensaios realizados, especialmente, em relação à remoção de matéria orgânica, cianobactérias e cor. As concentrações máximas de SOH encontrados nos efluentes do FRD e do FCAG não ultrapassaram os valores limites da Portaria nº 2.914/2011 do Ministério da Saúde.

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The current study investigated oxidative stress parameters (enzymes activities, metallothionein content and lipid peroxidation) in freshwater fish, Oreochromis niloticus, tilapia exposure to Monjolinho River (in 4 months of year: January, April, July and November). One critical site in Monjolinho River (site B) was assessed in comparison to a reference site (site A). Water pH and oxygen concentration was lower than that recommended by CONAMA (Brazilian National Environmental Committee), resolution 357/2005 for protection of aquatic communities, and ammonium and the metals Cu, Zn, Mn and Fe (on all months) concentrations were higher than the maximum concentration recommended. Glutathione peroxidase (GPx) and superoxide dismutase (SOD) activities were significantly decreased in liver and muscle in tila. pia from Monjolinho River, throughout the year, in relation to reference except in gills that SOD activity increased. Glutathione S-transferase (GST) activity was significantly increased in liver of the tilapia from Monjolinho River in all sites, in relation to reference except in gills that GST activity increased in July and decreased in November, suggesting that GST activity could be induced to neutralize the pollutants toxicity. On the other hand, GST activity was significantly decreased in white muscle indicating a toxic effect of pollutants, resulting in a decreased ability of tilapia to perform defense reactions associated to GSTs. The decrease of catalase (CAT) activity in gills of the O. niloticus together with the increase of SOD activity, could explain the increased lipid peroxidation (LPO) level in this organ. Metallothionein levels in liver and gills were significantly high in all sites. Results indicate that the exposure to metals caused severe damage to tissues; despite the consensually assumed antioxidant induction as a sign of exposure to contaminants the effects seem in part to be mediated by suppression of antioxidant system with SOD, CAT and GPx as potential candidates for tissues toxicity biomarkers of pollutants. (c) 2012 Elsevier Ltd. All rights reserved.

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Syntesis of carbon nanomaterials from corn waste (DDGS). The world's largest ethanol producer (USA) uses corn as feedstock. DDGS (distillers dried grains with solubles) is the main waste generated from this process (around 32 million t/year). DDGS samples were pyrolyzed at 1000 degrees C in a furnace with controlled atmosphere. The effluent was channeled to a second furnace, in which catalyst substrates were placed. Chromatographic analysis was used to evaluate the gaseous effluents, showing that the catalyst reduced hydrocarbon emissions. The solid products formed were analyzed by SEM and TEM. Graphitic structures and carbon nanofibers, 50 mu m in length and with diameters of 80-200 nm, were formed.

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Nuclear abnormalities in erythrocytes (NAE) were taken as biomarkers in the catfish Cathorops spixii (Ariidae) sampled in an estuary little affected by human activity (Cananeia) and in three regions (Santos Channel: SC, Santos Bay: SB and Sao Vicente Channel: SVC) of the Santos-Sao Vicente estuary impacted by various anthropogenic activities. Increases in NAE were observed in fish from SC and SVC sampled in the summer period as compared with specimens from the Cananeia estuary. These results suggest the presence of genotoxic compounds in these regions. However, the absence of significant differences in micronuclei frequency reflects slight mutagenic effects in these individuals. It is possible that the lower NAE frequency in specimens from SB might be associated with the greater remobilization and dilution of chemicals in this region. The low frequency of NAE in C. spixii from the Cananeia estuary is in accordance with the slight anthropogenic influence in this system, and may be suggestive of the absence of genotoxic and mutagenic effects in these organisms.

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This study investigated the application of an advanced oxidation process combining hydrogen peroxide with ultraviolet radiation (H2O2/UV) to remove recalcitrant compounds from Kraft bleaching effluent. Anaerobic pre-treatment was performed to remove easily degraded organics using a horizontal-flow anaerobic immobilized biomass (HAIB) reactor. Bleaching plant effluent was treated in the HAIB reactor processed over 19 h of hydraulic retention time (HRT), reaching the expected removal efficiencies for COD (61 +/- 3%), TOC (69 +/- 9%), BOD5 (90 +/- 5%) and AOX (55 +/- 14%). However, the anaerobic treatment did not achieve acceptable removal of UV254 compounds. Furthermore, there was an increase of lignin, measured as total phenols. The H2O2/UV post-treatment provided a wide range of removal efficiencies depending on the dosage of hydrogen peroxide and UV irradiation: COD ranged from 0 to 11%, UV254 from 16 to 35%, lignin from 0 to 29% and AOX from 23 to 54%. All peroxide dosages applied in this work promoted an increase in the BOD5/COD ratio of the wastewater. The experiments demonstrate the technical feasibility of using H2O2/UV for post-treatment of bleaching effluents submitted to anaerobic pre-treatment.

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Different components of the mixed function oxidase (MFO) system and the levels of fluorescent aromatic compounds in bile (FACs) were measured in Cathorops spixii in order to assess the impact of polycyclic aromatic hydrocarbons (PAHs). Fish were sampled in an estuary (Santos/Sao Vicente) with a history of contamination by PAHs, mainly due to the presence of the industrial complex of Cubatao city and of another of low anthropogenic influence (Cananeia) on the Brazilian coast. FACs were higher in fish from the polluted site, and the PAH 5 and 6-ring metabolites were the most frequent - with 14% and 15%, respectively. Levels of the different components of the MFO system showed the same variation profile as the FACs for both estuaries. Therefore, the values found for somatic indexes and biomarkers with data of bile PAH metabolites indicate the presence of organic contaminants, especially in the area subject to the influence of the industrial complex on the Santos/Sao Vicente estuary.

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O objetivo deste trabalho foi quantificar o aporte e a remoção de nutrientes em sistemas de cultivo  de cana‑de‑açúcar irrigados, ou não, com efluente de estação de tratamento de esgoto (EETE), com e sem  adição  de fosfogesso,  bem  como  avaliar  os  efeitos  desses sistemas  de  cultivo  no  estado  nutricional  das  plantas. Foram avaliados tratamentos sem irrigação e com irrigação a 100 e 150% da necessidade hídrica da  cultura. Os tratamentos com fosfogesso foram aplicados em área de terceiro corte, irrigada com EETE desde  o plantio. As  avaliações foram realizadas em duas safras. Os tratamentos não afetaram os rendimentos de  colmos. O tratamento com EETE e fosfogesso apresentou efeito sinérgico sobre o conteúdo de nitrogênio e de  enxofre nas plantas. O EETE beneficiou a nutrição das plantas quanto ao fósforo, mas não causou melhorias  na nutrição com potássio e enxofre. A nutrição com ferro, zinco e manganês não foi influenciada pelo aporte  desses micronutrientes pelo EETE. O  fósforo e o nitrogênio aportados na irrigação com EETE devem ser  considerados na recomendação de adubação. Porém, potássio, enxofre, ferro, zinco e manganês do efluente não  são fontes eficientes desses nutrientes para as plantas.

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Purpose: There is no consensus on the optimal method to measure delivered dialysis dose in patients with acute kidney injury (AKI). The use of direct dialysate-side quantification of dose in preference to the use of formal blood-based urea kinetic modeling and simplified blood urea nitrogen (BUN) methods has been recommended for dose assessment in critically-ill patients with AKI. We evaluate six different blood-side and dialysate-side methods for dose quantification. Methods: We examined data from 52 critically-ill patients with AKI requiring dialysis. All patients were treated with pre-dilution CWHDF and regional citrate anticoagulation. Delivered dose was calculated using blood-side and dialysis-side kinetics. Filter function was assessed during the entire course of therapy by calculating BUN to dialysis fluid urea nitrogen (FUN) ratios q/12 hours. Results: Median daily treatment time was 1,413 min (1,260-1,440). The median observed effluent volume per treatment was 2,355 mL/h (2,060-2,863) (p<0.001). Urea mass removal rate was 13.0 +/- 7.6 mg/min. Both EKR (r(2)=0.250; p<0.001) and K-D (r(2)=0.409; p<0.001) showed a good correlation with actual solute removal. EKR and K-D presented a decline in their values that was related to the decrease in filter function assessed by the FUN/BUN ratio. Conclusions: Effluent rate (ml/kg/h) can only empirically provide an estimated of dose in CRRT. For clinical practice, we recommend that the delivered dose should be measured and expressed as K-D. EKR also constitutes a good method for dose comparisons over time and across modalities.

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Este estudo teve como objetivo avaliar alguns impactos decorrentes do deslocamento miscível de efluente de nitração de uma indústria de explosivos aplicado em colunas de um Latossolo Amarelo, horizonte B (LA-B), submetido aos tratamentos: adição de carbonatos (BASE), ácidos (ACID), fosfato (FOSF), carbonatos e fosfato (BASE-FOSF) e ácidos e fosfatos (ACID-FOSF). A recuperação de nitrogênio em relação ao total aplicado varia entre 10,1 (ACID) e 65,5% (BASE). Há correlação significativa entre as curvas de transposição de N obtidas experimentalmente e as simuladas pelo aplicativo STANMOD para a maioria das colunas (p<0,001). A exceção ocorreu para ACID-FOSF (p=0,202). Não há correlação entre carga eletrostática líquida (CEL) e as variáveis de ajuste do modelo: fator de retardamento (FR), coeficiente de dispersão-difusão (D) e taxa de decaimento de primeira ordem m (µ). A adição de fosfato (FOSF) favorece a movimentação do nitrogênio, pois diminui FR (2,35±0,05) e µ (0,498±0,050 h-1) e aumenta D (41,8±5,5 cm2 h-1) em relação ao observado na coluna LA-B (2,51±0,03; 1,697±0,084 h-1e 2,8±1,3 cm2 h-1 respectivamente). A adição de carbonatos e/ou fosfatos (BASE, BASE/FOSF e FOSF) resultou nos maiores valores máximos de demanda química de oxigênio (DQOMÁX). A pequena quantidade de DNA extraída das células bacterianas nos solos sugere que, possivelmente, os processos que governam a adsorção e movimentação de N sejam de natureza não biológica ou que a elevada DQO do líquido percolado prejudica os microrganismos do solo.

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The effect of substrate (glucose) concentration on the stability and yield of a continuous fermentative process that produces hydrogen was studied. Four anaerobic fluidized bed reactors (AFBRs) were operated with a hydraulic retention time (HRT) from 1 to 8 h and an influent glucose concentration from 2 to 25 gL(-1). The reactors were inoculated with thermally pre-treated anaerobic sludge and operated at a temperature of 30 degrees C with an influent pH around 5.5 and an effluent pH of about 3.5. The AFBRs with a HRT of 2 h and a feed strength of 2, 4, and 10 gL(-1) showed satisfactory H-2 production performance, but the reactor fed with 25 gL(-1) of glucose did not. The highest hydrogen yield value was obtained in the reactor with a glucose concentration of 2 gL(-1) when it was operated at a HRT of 2 h. The maximum hydrogen production rate value was achieved in the reactor with a HRT of 1 h and a feed strength of 10 gL(-1). The AFBRs operated with glucose concentrations of 2 and 4 gL(-1) produced greater amounts of acetic and butyric acids, while AFBRs with higher glucose concentrations produced a greater amount of solvents.