998 resultados para pulp and paper mill process water


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This paper describes the hydrochemistry of a lowland, urbanised river-system, The Cut in England, using in situ sub-daily sampling. The Cut receives effluent discharges from four major sewage treatment works serving around 190,000 people. These discharges consist largely of treated water, originally abstracted from the River Thames and returned via the water supply network, substantially increasing the natural flow. The hourly water quality data were supplemented by weekly manual sampling with laboratory analysis to check the hourly data and measure further determinands. Mean phosphorus and nitrate concentrations were very high, breaching standards set by EU legislation. Though 56% of the catchment area is agricultural, the hydrochemical dynamics were significantly impacted by effluent discharges which accounted for approximately 50% of the annual P catchment input loads and, on average, 59% of river flow at the monitoring point. Diurnal dissolved oxygen data demonstrated high in-stream productivity. From a comparison of high frequency and conventional monitoring data, it is inferred that much of the primary production was dominated by benthic algae, largely diatoms. Despite the high productivity and nutrient concentrations, the river water did not become anoxic and major phytoplankton blooms were not observed. The strong diurnal and annual variation observed showed that assessments of water quality made under the Water Framework Directive (WFD) are sensitive to the time and season of sampling. It is recommended that specific sampling time windows be specified for each determinand, and that WFD targets should be applied in combination to help identify periods of greatest ecological risk. This article is protected by copyright. All rights reserved.

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Thermal Lens Spectrometry has traditionally been carried out in the single-beam and the mode-mismatched dual-beam configurations. Recently, a much more sensitive dual-beam TL setup was developed, where the probe beam is expanded and collimated. This feature optimizes Thermal Lens (TL) signal and allows the use of thicker samples, further improving the sensitivity. In this paper, we have made comparisons between the conventional and optimized TL configurations, and presented applications such as measurements of very low absorptions and concentrations in water and Cr(III) aqueous solution in the UV-vis range. For pure water we found linear absorption coefficients as low as the Raman scattering one due to the stretching vibrational modes of OH group. The detection limit was estimated 1 x 10(-6) cm(-1) with a 180-mW excitation power using a 100-mm cell length. This sensitivity is very high, considering that water has a photothermal enhancement factor similar to 33 times smaller than CCl(4), for example. For Cr(III) species in aqueous solution, the limit of detection (LOD) was estimated in similar to 40 ng mL(-1) at 514 nm, or similar to 10ng mL(-1) at 405 nm, which is similar to 30 times smaller than the LOD achieved with conventional transmission techniques. The more recent TL configuration is very attractive to obtain absorption spectra, since the result does not depend critically on the beam parameters, unlike the other configurations. The main drawbacks of this optimized TL configuration are the longer acquisition time and the need for larger samples. (C) 2011 Published by Elsevier B.V.

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Over the last 40 years there has been a profusion of studies about the ccumulation of technological capacities in firms from developing economies. However, there remain few studies that examine, on a combined basis, the relationship among: the trajectories of technological capacities accumulation; the underlying learning mechanisms; and, the implications of organizational factors for these two variables. Still scarcer are the studies that examine the relationship among these variables along time and based on a comparative case study. This dissertation examines the relationship among the trajectory of accumulation of innovative capacities in complex project management, the learning mechanisms underlying these technological capacities and the intra-organizational factors that influence these learning echanisms. That set of relationships is examined through a comparative and a long-term (1988-2008) case study in a capital goods firm (for the pulp and paper industry) and a pulp mill in Brazil. Based on first-hand quantitative and qualitative empiric evidence, gathered through extensive field research, this dissertation found: 1. Both firms accumulated innovative capacity in project management at the international frontier level (Level 6). However, there was variability between the firms in terms of the nature and speed of accumulation of those capacities. It was also observed that, at this level of innovation, the innovative capacities of both firms are not confined to their organizational boundaries, but they are distributed beyond their boundaries. 2. So that these companies could accumulate those levels of innovative capacities it was necessary to manage several learning mechanisms: leveraging of external knowledge and its internalization in terms of internal apacities of the firm. In other words, as the companies accumulated more innovative levels of capacities for project management, it was necessary to manage different cycles of technological learning. 3. Further, the relationship between the ccumulation of technological capacities and learning was affected positively by intra-organizational factors, such as 'authority disposition', 'mutability of work roles' and 'intensity of internal crises', and negatively by the factor 'singularity of goals'. This dissertation revealed divergent results between firms in two of the four factors studied. These results contribute to advance our understanding of the complexity and variability involved in the process of accumulation of innovative capacities in firms from developing economies. This highlights the growing importance of the organizational and the human resource dimensions of innovation and technological capacity as the company approaches the international frontier. The results suggest to managers that: (i) the good performance in project management in the two firms studied did not occur simply as a result of the pulp and paper Brazilian industry growth, rather as a result of the deliberate construction and accumulation of the capacities through an intensive and coordinated cyclical process of technological learning, (ii) to develop innovative capabilities in project management, besides looking for learning mechanisms they should also look at the organizational factors that influence the learning mechanisms directly, (iii) performance of pulp mill¿s projects is better when projects are implemented together with technology suppliers than when performed only by the mill. This dissertation concludes that capital goods firms have been having a fundamental role for the innovative capabilities accumulation in project management of pulp mills in Brazil (and vice-versa) for a long time. This contradicts some authors' propositions that affirm that: a) equipment suppliers for the pulp and paper industry have been creating little, if any, development of processes or engineering projects in Brazil; b) firms in the pulp and paper industry have little capacity for machinery and equipments projects only taking place in few technological activities, being internal or external to the firm. Finally, some studies are proposed for future research.

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The volatiles (VOCs) and semi-volatile organic compounds (SVOCs) responsible for aroma are mainly present in skin of grape varieties. Thus, the present investigation is directed towards the optimisation of a solvent free methodology based on headspace-solid-phase microextraction (HS-SPME) combined with gas chromatography–quadrupole mass spectrometry (GC–qMS) in order to establish the global volatile composition in pulp and skin of Bual and Bastardo Vitis vinifera L. varieties. A deep study on the extraction-influencing parameters was performed, and the best results, expressed as GC peak area, number of identified compounds and reproducibility, were obtained using 4 g of sample homogenised in 5 mL of ultra-pure Milli-Q water in a 20 mL glass vial with addition of 2 g of sodium chloride (NaCl). A divinylbenzene/carboxen/polydimethylsiloxane fibre was selected for extraction at 60 °C for 45 min under continuous stirring at 800 rpm. More than 100 VOCs and SVOCs, including 27 monoterpenoids, 27 sesquiterpenoids, 21 carbonyl compounds, 17 alcohols (from which 2 aromatics), 10 C13 norisoprenoids and 5 acids were identified. The results showed that, for both grape varieties, the levels and number of volatiles in skin were considerably higher than those observed in pulp. According to the data obtained by principal component analysis (PCA), the establishment of the global volatile signature of grape and the relationship between different part of grapes—pulp and skin, may be an useful tool to winemaker decision to define the vinification procedures that improves the organoleptic characteristics of the corresponding wines and consequently contributed to an economic valorization and consumer acceptance.

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Organizations are Complex systems. A conceptual model of the enterprise is needed that is: coherent the distinguished aspect models constitute a logical and truly integral comprehensive all relevant issues are covered consistent the aspect models are free from contradictions or irregularities concise no superfluous matters are contained in it essential it shows only the essence of the enterprise, i.e., the model abstracts from all realization and implementation issues. The world is in great need for transparency about the operation of all the systems we daily work with, ranging from the domestic appliances to the big societal institutions. In this context the field of enterprise ontology has emerged with the aim to create models that help to understand the essence of the construction and operation of complete systems; more specifically, of enterprises. Enterprise ontology arises in the way to look through the distracting and confusing appearance of an enterprise right into its deep kernel. This, from the perspective of the system designer gives him the tools needed to design a successful system in a way that’s reflects the desires and needs of the workers of the enterprise. This project’s context is the use of DEMO (Design and Engineering Methodology for Organizations) for (re)designing or (re)engineering of an enterprise, namely a process of the construction department of a city hall, the lack of a well-founded theory about the construction and operation of this processes that was the motivation behind this work. The purpose of studying applying the DEMO theory and method was to optimize the process, automating it as much as possible, while reducing paper and time spent between tasks and provide a better service to the citizens.

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In this paper a new algorithmic of Analog-to-Digital Converter is presented. This new topology use the current-mode technique that allows a large dynamic range and can be implemented in digital CMOS process. The ADC proposed is very small and can handle high sampling rates. Simulation results using a 1.2um CMOS process show that an 8-b ADC can support a sampling rate of 50MHz.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The purpose of this paper was to develop a model for calculating the economical flow diameter and velocity, by obtaining the economical diameter, using Swamee's friction factor equation, by minimizing the total annual cost. The application of the model to a regular supply condition showed that the diameter of the actual condition, 250 mm, compared with the diameter calculated by the mode, at the same tariff as that applied to the property ( ground), 284.1 mm, involved the necessity to generate, transmit, and distribute extra electrical energy, due to the higher load loss caused by the original diameter, approximately 30800 kWh/year. This means that in one year, the consumer would spend R$2,804.00 more on pumping cost alone.

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Vegetable oils are important sources of essential fatty acids. It is, therefore, important to characterize plant species that can be used as new oil sources. This study aimed to characterize the oils from guariroba (Syagrus oleracea), jeriva (Syagrus romanzoffiana), and macauba (Acrocomia aculeata). The physicochemical characterization was performed using official analytical methods for oils and fats, free fatty acids, peroxide value, refractive index, iodine value, saponification number, and unsaponifiable matter. The oxidative stability was determined using the Rancimat at 110 degrees C. The fatty acid composition was performed by gas chromatography. The results were submitted to Tukey's test for the medium to 5% using the ESTAT program. The pulp oils were more unsaturated than kernel oils, as evidenced by the higher refractive index and iodine value, especially the macauba pulp oil which gave 1.4556 and 80 g I(2)/100 g, respectively, for these indices. The kernel oils were less altered by oxidative process and had high induction period, free fatty acids below 0.5%, and peroxide value around 0.19 meq/kg. The guariroba kernel oil showed the largest induction period, 91.82 h.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Iridium-, Ru-, and W-coated platforms were prepared by thermal treatment of the transversely heated graphite atomizer and investigated for the simultaneous determination of As, Bi, Pb, Sb, and Se in tap water by electrothermal atomic absorption spectrometry. The maximum pyrolysis temperature for As and Bi increased in a modifier sequence W < Ru < Ir. For Pb, Sb, and Se, this sequence was W < Ru, It. Calculated characteristic masses in the presence of It, Ru, and W were 35, 33, and 35 pg for As; 63, 51, and 52 pg for Bi; 50, 32, and 34 pg for Pb; 40, 35, and 31 pg for Sb; and 39, 39, and 93 pg for Se, respectively. Ruthenium was elected as the optimum modifier.Repeatability of the measurements was typically < 6%. Recoveries of As, Bi, Pb, Sb, and Se added to tap water samples varied from 79 to 109%. Accuracy was also checked by analysis of five certified reference materials (CRMs) from the National Institute of Standards and Technology (NIST1640 - Trace Elements in Natural Water; NIST 1643d Trace Elements in Water) and High Purity Standards (Trace Metals in Drinking Water Standards, lots #812708, #591107, and #710710). A paired t-test showed that the results for the CRMs were in agreement at the 95% confidence level with the certified values. The graphite tube lifetime was about 650 firings. multi-element determination is particularly challenging due to the necessity of carefully optimizing compromise conditions.Based on the considerations listed above, the aim of this paper was to evaluate the behavior of Ir, Ru, and W as permanent modifiers for the simultaneous determination of As, Bi, Pb, Sb, and Se. The performance of the proposed procedure was also verified after the ETAAS analysis of tap waters and reference materials.

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Scanning electron microscopy (SEM) was used to investigated the effects of volatile solvents (such as water, propanone, ethanol, methanol or ethyl ether), treatment and drying processes, microwave ovens, drying ovens, and vacuum desiccators or freeze driers, on silica morphology. Silica gel was obtained from diluted sodium silicate (1:5 w/w SiO2:H2O). The results showed that the drying process based on freeze drying is more efficient for structural conservation of the precipitate. Treatment with volatile solvents does not change the shape of the aggregates, but has an important role in the determination of aggregate surface roughness.

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The intermittent milling and dynamic steeping (IMDS) process is an alternative method developed for wet milling of maize. In this process, the steeping stage can be reduced to 5 h by soaking maize in water at 60°C for 2 h and cracking the kernels to remove solution components diffusional barriers with minimum germ damage. Maize was dynamically steeped in solutions with 0.0, 0.1, and 0.2% sulphur dioxide (SO2) and 0.00, 0.55% lactic acid. Germ recovery, germ damage, fibre in germ, oil content and uncracked kernels were determined. A conventional steeping procedure was also performed. Germ recovery was higher for all tests using both SO2 and lactic acid than for the others with best germ yield for concentrations of 0.2% SO2 and 0.55% lactic acid. Germ damage ranged from 7.4 to 18.2% for all tests. The presence of lactic acid in the steeping solution decreased the amount of fibre in germ fraction. Germ oil content ranged from 39.3% (0-0% SO2, 0.55% lactic acid) to 44.0% (0.2% SO2, 0.55% lactic acid) for all treatments using IMDS. The smallest difference was 5.5% between IMDS (0.2% SO2, 0.55% lactic acid) and the conventional 36 h steeping process. An average of 1.3% of kernels remained uncracked after IMDS process. © 2002 Silsoe Research Institute. Published by Elsevier Science Ltd. All rights reserved.

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The present study aimed to compare the attractiveness of industrial citrus pulp with the handmade orange albedo to the workers of Atta sexdens rubropilosa. For this, filter paper fragments were impregnated with organic extracts obtained through chemical extraction and sequential fractioning with hexane and dichloromethane and offered to different field nests. It was verified that the industrial citrus pulp extract is as good as the handmade orange albedo extract. This preference is discussed keeping in mind the chemical, behavioral and nutritional factors.