Preparação e caracterização de um material híbrido, à base de vermiculita modificada com quitosana, para a remoção de íons de chumbo presentes em efluentes sintéticos

Actually, surveys have been developed for obtaining new materials and methodologies that aim to minimize environmental problems due to discharges of industrial effluents contaminated with heavy metals. The adsorption has been used as an alternative technology effectively, economically viable and potentially important for the reduction of metals, especially when using natural adsorbents such as certain types of clay. Chitosan, a polymer of natural origin, present in the shells of crustaceans and insects, has also been used for this purpose. Among the clays, vermiculite is distinguished by its good ion exchange capacity and in its expanded form enhances its properties by greatly increasing its specific surface. This study aimed to evaluate the functionality of the hybrid material obtained through the modification of expanded vermiculite with chitosan in the removal of lead ions (II) in aqueous solution. The material was characterized by infrared spectroscopy (IR) in order to evaluate the efficiency of modification of matrix, the vermiculite, the organic material, chitosan. The thermal stability of the material and the ratio clay / polymer was evaluated by thermogravimetry. To evaluate the surface of the material was used in scanning electron microscopy (SEM) and (BET). The BET analysis revealed a significant increase in surface area of vermiculite that after interaction with chitosan, was obtained a value of 21, 6156 m2 / g. Adsorption tests were performed according to the particle size, concentration and time. The results show that the capacity of removal of ions through the vermiculite was on average 88.4% for lead in concentrations ranging from 20-200 mg / L and 64.2% in the concentration range of 1000 mg / L. Regarding the particle size, there was an increase in adsorption with decreasing particle size. In fuction to the time of contact, was observed adsorption equilibrium in 60 minutes with adsorption capacity. The data of the isotherms were fitted to equation Freundlich. The kinetic study of adsorption showed that the pseudo second- order model best describes the adsorption adsorption, having been found following values K2=0,024 g. mg-1 min-1and Qmax=25,75 mg/g, value very close to the calculated Qe = 26.31 mg / g. From the results we can conclude that the material can be used in wastewater treatment systems as a source of metal ions adsorbent due to its high adsorption capacity

Estudo de um sistema híbrido de destilação solar para polimento de águas produzidas

The oil industry, experiencing a great economic and environmental impact, has increasingly invested in researches aiming a more satisfactory treatment of its largest effluent, i.e., produced water. These are mostly discarded at sea, without reuse and after a basic treatment. Such effluent contains a range of organic compounds with high toxicity and are difficult to remove, such as polycyclic aromatic hydrocarbons, salts, heavy metals, etc.. The main objective of this work was to study the solar distillation of produced water pre-treated to remove salts and other contaminants trough of a hybrid system with a pre-heater. This developed apparatus was called solar system, which consists of a solar heater and a conventional distillation solar still. The first device consisted of a water tank, a solar flat plate collector and a thermal reservoir. The solar distillator is of simple effect, with 1m2 of flat area and 20° of inclination. This dissertation was divided in five steps: measurements in the solar system, i.e. temperatures and distillate flow rate and weather data; modeling and simulation of the system; study of vapor-liquid equilibrium of the synthetic wastewater by the aqueous solution of p-xylene; physical and chemical analyses of samples of the feed, distillate and residue, as well as climatology pertinent variables of Natal-RN. The solar system was tested separately, with the supply water, aqueous NaCl and synthetic oil produced water. Temperature measurements were taken every minute of the thermal reservoir, water tank and distillator (liquid and vapor phases). Data of solar radiation and rainfall were obtained from INPE (National Institute for Space Research). The solar pre-heater demonstrated to be effective for the liquid systems tested. The reservoir fluid had an average temperature of 58°C, which enabled the feed to be pre-heated in the distillator. The temperature profile in the solar distillator showed a similar behavior to daily solar radiation, with temperatures near 70°C. The distillation had an average yield of 2.4 L /day, i.e., an efficiency of 27.2%. Mathematical modeling aided the identification of the most important variables and parameters in the solar system. The study of the vapor-liquid equilibrium from Total Organic Carbon (TOC) analysis indicated heteroazeotropia and the vapor phase resulted more concentrated in p-xylene. The physical-chemical analysis of pH, conductivity, Total Dissolved Solids (TDS), chlorides, cations (including heavy metals) and anions, the effluent distillate showed satisfactory results, which presents a potential for reuse. The climatological study indicates the region of Natal-RN as favorable to the operation of solar systems, but the use of auxiliary heating during periods of higher rainfall and cloud cover is also recommended

Extração, caracterização e avaliação bioativa do extrato de Rumex acetosa

Studies show the great influence of free radicals and other oxidants as responsible for aging and degenerative diseases. On the other hand, the natural phenolic compounds has shown great as antioxidants to inhibit lipid peroxidation and lipoxygenase in vitro. Among these, is highlighted trans-resveratrol ( 3,5,4 `- trihydroxystilbene ) phenolic compound , characterized as a polyphenol stilbene class. The vegetables popularly known as "Azedinha" (Rumex Acetosa) has trans-resveratrol in its composition and from this, the present work aimed to study on the supercritical extraction and conventional extraction (Soxhlet and sequential) in roots of Rumex Acetosa, evaluating the efficiency of extractive processes, antioxidant activity, total phenolic content and quantification of trans-resveratrol contained in the extracts. Extractions using supercritical CO2 as solvent, addition of co-solvent (ethanol) and were conducted by the dynamic method in a fixed bed extractor. The trial met a 23 factorial design with three replications at the central point, with the variable reply process yield and concentration of trans-resveratrol and pressure as independent variables, temperature and concentration of co-solvent (% v/v). Yields ( mass of dry extract / mass of raw material used ) obtained from the supercritical extraction ranged from 0,8 to 7,63 % , and the best result was obtained at 250 bar and 90 °C using the co-solvent 15% ethanol (% v/v). The value was calculated for YCER a flow rate of 1,0 ± 0,17 g/min resulting in 0,0469 CO2 ( g solute / g solvent ). The results of the mass yield varied between conventional extractions 0,78 % ( hexane) and 9,97 % (ethanol). The statistical model generated from the data of the concentration of trans-resveratrol performed as meaningful and predictive for a 95% confidence. GC analysis on HPLC (High Performance Liquid Chromatography), transresveratrol was quantified in all extracts and concentration values ranged between 0,0033 and 0,42 ( mg / g extract) for supercritical extracts and between 0,449 and 17,046 (mg / g extract) to conventional extractions and therefore, the Soxhlet extraction with ethanol for more selective trans-resveratrol than the supercritical fluid. Evaluation of antioxidant (radical method to sequester 2,2- diphenyl-1- picryl - hydrazyl - DPPH) the supercritical extracts resulted in EC50 values (concentration effective to neutralize 50% of free radicals) of between 7,89 and 18,43 mg/mL , while resulting in a Soxhlet extraction with EC50 values in the range of 6,05 and 7,39 mg/mL. As for quantification of the phenolic compounds (Method Spectrophotometer Folin-Ciocalteau) the supercritical extracts resulted in values between 85,3 and 194,79 mg GAE / g extract, whereas values derived from the Soxhlet extract resulted in values between 178,5 and 237,8 mg GAE / g extract. The high antioxidant activity can not be attributed solely to the presence of phenolic compounds, but the presence of other antioxidants in the existing Rumex acetosa

Influência da intensidade de aeração na formação do floco de lodo ativado e na eficiência de remoção de matéria orgânica

In wastewater treatment, activated sludge systems have been a technology widely applied as secondary treatment. During this step, which has a strong biological aspect, it is necessary to introduce oxygen supply for the maintenance of metabolic activity of the bacteria through the aerators. Aeration devices are responsible for most of the energy consumption in this stage. In this background, the influence of three aeration intensities (atmospheric air flow 3.5, 7.0 and 10.5 L.min-1) and the concentration of dissolved oxygen (DO) on the dimension of activated sludge flocs as well as on the efficiency of organic matter removal were assessed using a traditional activated sludge system which was fed with synthetic domestic wastewater. Samples were taken weekly from the three units that make up the system feed, aeration and storage tank in order to verify the Chemical Oxygen Demand (COD). It was established the process efficiency through a comparison between the initial and final COD. Besides the parameters already mentioned, this monitoring work on activated sludge batch system was also observed by Mixed Liquor Suspend Solids (MLSS), Volatile Suspend Solids (VSS), pH and temperature measures. The results have showed a maximum removal efficiency around 75% in the first aeration sequence and approximately 85% for the second and third one. For the first aeration, the DO concentration remained higher than 3.0 mg.L-1 and a diameter range from 10 to 60 μm was observed. In the second e third sequence, the DO concentration remained higher than 4.0 mg.L-1 with a diameter range of 10 until 200 μm. Although the sequence 1 and 2 have presented similar performances for organic matter removal, the sequence 2 promoted a regular floc size distribution and with lower values of Sludge Volumetric Index (SVI) meaning a better flocculating ability. In addition, the results reaffirmed what the literature has reported: higher DO concentrations produce flocs with greater dimensions

Extração de metais pesados de efluentes da indústria do petróleo utilizando derivados de óleos vegetais como extratantes

The study of a promising alternative for the treatment of produced water from the oil industry envisaging its reuse was the focus of this work. Millions of liters of water are generated per day, containing heavy metals in low concentrations (< 0,15 mg/L for Pb, <0,04 mg/L for Cd, <0,04 mg/L for Ni). The technology applied to extract these metals from aqueous phase was the solvent extraction and the extratants used were vegetable oils originated from coconut oil. They can be used in natural form or as derivatives, known as MAC - Mixture of Carboxílics Acids. The determination of the heavy metal con¬centrations in a complex matrix was made by using the atomic absorption spectrometry technique (AAS). On the bench tests using synthetics aqueous solutions containing metals, vegetable oils showed no power to extract the metals studied. The extractant MAC was selective for the Pb> Cd> Ni, in the concentration of 8% in the same organic phase. In this condition, the lower efficiency of extraction obtained was 92% for the Pb, 69% for the Cd, in the range of pH ranging from 6 to 8. An experimental planning was conducted for continuous tests. The device used was called MDIF Misturador-Decantador à Inversão de Fases and the aqueous phase was produced water from Pólo Indutrial de Guamaré/RN . No correlation between the studied variables (concentration of metal, concentration of extratant and agitation in the mixing chamer) could be obtained, because of possible factors which occurred as: variation in the composition of the studied sample, phenomena of precipitation and complexation of metals in the reservoir of feed, solubility of extratant

Estudo da viabilidade da destilação solar para polimento de águas produzidas de petróleo

This work study of solar distillation feasibility in effluent of petroleum industry: produced water, making possible your reuse for irrigation of oleaginous cultures or fodder crops or in steam generation, as well the transport phenomena involved. The methodology for development of this project was to characterize the effluent to be treated and to accomplish physical and chemical analysis in the distilled, to build distillation equipment, concomitant operation of both equipments and implementation of data processing and economical evaluation. The methodology used for all parameters is outlined in APHA (1998) and sampling of the type compound. The feeding of distillation equipment was performed with treated effluent from UTPF of Guamaré. The temperature was monitored throughout the distillers and during the time of operation. The distillers feed occur, as a rule, for sifon. The distillers were operated by a period of 17 months between July 2007 and February 2009, in which 40 experiments were performed. The radiation and temperature datas were acquired in the INPE s site and the temperature inside of the distillers was registered by DATALOGGER Novus. The rates of condensation (mL / min) were determined by measuring of the flow in a graduate test tube of 10 mL and a chronometer. We used two simple solar effect distillers of passive type with different angles in coverage: 20 ° and 45 °. The results obtained in this study and the relevant discussions are divided into six topics: sample characterization and quality of distilled; construction of distillers; operation (data, temperature profile), climatic aspects, treatment of data and economical analysis. Results obtained can be inferred that: the energy loss by the adoption of vessel glass was not significant, however, complicates the logistics of maintenance the equipment on a large scale. In the other hand, the surface of the tub with a glass shield on the equipment deterioration, both devices showed similar performance, so there is not justified for use of equipment 450. With regard to the climatological study it was verified that the Natal city presents monthly medium radiation varying in a range between 350 and 600 W/m2, and medium of wind speed of 5 m / s. The medium humidity is around 70% and rainfall is very small. The regime of the system is transient and although it has been treated as a stationary system shows that the model accurately represents the distillers system's 20 degrees. The quality of the distilled with regard to the parameters evaluated in this study is consistent with the Class 3 waters of CONAMA (Resolution 357). Therefore we can conclude that solar distillation has viability for treat oilfield produced water when considered the technical and environmental aspects, although it is not economically viable

Recuperação e purificação de proteínas do soro de queijo tipo coalho usando cromatografia de troca iônica e interação hidrofóbica em leito na forma expandida

Expanded Bed Adsorption plays an important role in the downstream processing mainly for reducing costs as well as steps besides could handling cells homogenates or fermentation broth. In this work Expanded Bed Adsorption was used to recover and purify whey proteins from coalho cheese manufacture using Streamline DEAE and Streamline SP both ionic resins as well as a hydrophobic resin Streamline Phenyl. A column of 2.6 cm inner diameter with 30 cm in height was coupled to a peristaltic pump. Hydrodynamics study was carried out with the three resins using Tris-HCl buffer in concentration of 30, 50 and 70 mM, with pH ranging from 7.0 to 8.0. In this case, assays of the expansion degree as well as Residence Time Distribution (RTD) were carried out. For the recovery and purification steps, a whey sample of 200 mL, was submitted to a column with 25mL of resin previously equilibrated with Tris/HCl (50 mM, pH 7.0) using a expanded bed. After washing, elution was carried out according the technique used. For ionic adsorption elution was carried out using 100 mL of Tris/HCl (50 mM, pH 7.0 in 1M NaCl). For Hydrophobyc interaction elution was carried out using Tris/HCl (50 mM, pH 7.0). Adsorption runs were carried out using the three resins as well as theirs combination. Results showed that for hydrodynamics studies a linear fit was observed for the three resins with a correlation coefficient (R2) about 0.9. In this case, Streamline Phenyl showed highest expansion degree reaching an expansion degree (H0/H) of 2.2. Bed porosity was of 0.7 when both resins Streamline DEAE and Streamline SP were used with StremLine Phenyl showing the highest bed porosity about 0.75. The number of theorical plates were 109, 41.5 and 17.8 and the axial dipersion coefficient (Daxial) were 0.5, 1.4 and 3.7 x 10-6 m2/s, for Streamline DEAE, Streamline SP and Streamline Phenyl, respectively. Whey proteins were adsorved fastly for the three resins with equilibrium reached in 10 minutes. Breakthrough curves showed that most of proteins stays in flowthrough as well as washing steps with 84, 77 and 96%, for Streamline DEAE, Streamline SP and Streamline Phenyl, respectively. It was observed protein peaks during elution for the three resins used. According to these peaks were identified 6 protein bands that could probably be albumin (69 KDa), lactoferrin (76 KDa), lactoperoxidase (89 KDa), β-lactoglobulin (18,3 KDa) e α-lactoalbumin (14 KDa), as well as the dimer of beta-lactoglobulin. The combined system compound for the elution of Streamline DEAE applied to the Streamline SP showed the best purification of whey proteins, mainly of the α-lactoalbumina

Estudo de técnicas para o tratamento alternativo de efluentes oleosos oriundos da industrialização da castanha de caju

An evaluation project was conducted on the technique of treatment for effluent oil which is the deriving process to improve cashews. During the evaluation the following techniques were developed: advanced processes of humid oxidation, oxidative processes, processes of biological treatment and processes of adsorption. The assays had been carried through in kinetic models, with an evaluation of the quality of the process by means of determining the chemical demand of oxygen (defined as a technique of control by means of comparative study between the available techniques). The results demonstrated that the natural biodegradation of the effluent ones is limited, as result using the present natural flora in the effluent one revealed impracticable for an application in the industrial systems, independent of the evaluation environment (with or without the oxygen presence). The job of specific microorganisms for the oily composite degradation developed the viability technique of this route, the acceptable levels of inclusion in effluent system of treatment of the improvement of the cashew being highly good with reasonable levels of removal of CDO. However, the use combined with other techniques of daily pay-treatment for these effluent ones revealed to still be more efficient for the context of the treatment of effluent and discarding in receiving bodies in acceptable standards for resolution CONAMA 357/2005. While the significant generation of solid residues the process of adsorption with agroindustrial residues (in special the chitosan) is a technical viable alternative, however, when applied only for the treatment of the effluent ones for discarding in bodies of water, the economic viability is harmed and minimized ambient profits. Though, it was proven that if used for ends of I reuse, the viability is equalized and justifies the investments. There was a study of the photochemistry process which have are applicable to the treatment of the effluent ones, having resulted more satisfactory than those gotten for the UV-Peroxide techniques. There was different result on the one waited for the use of catalyses used in the process of Photo. The catalyses contained the mixing oxide base of Cerium and Manganese, incorporated of Potassium promoters this had presented the best results in the decomposition of the involved pollutants. Having itself an agreed form the gotten photochemistry daily paytreatment resulted, then after disinfection with chlorine the characteristics next the portability to the water were guarantee. The job of the humid oxidation presented significant results in the removal of pollutants; however, its high cost alone is made possible for job in projects of reuses, areas of low scarcity and of raised costs with the capitation/acquisition of the water, in special, for use for industrial and potable use. The route with better economic conditions and techniques for the job in the treatment of the effluent ones of the improvement of the cashew possesses the sequence to follow: conventional process of separation water-oil, photochemistry process and finally, the complementary biological treatment

Síntese de Fischer-Tropsch sobre perovskitas LayCu0,4Fe0,6O3

The current natural gas production of 52 Mm3d-1 and the large projects for its expansion has been setting new boundaries for the Brazilian industry of oil and gas. So far, one of the biggest challenges regards to the logistics for gas transportation from offshore fields. Therefore, the transformation of natural gas into gasoline, diesel and/or olefins via Fischer-Tropsch synthesis would be an alternative to this matter. In this work, the production of hydrocarbons by Fischer-Tropsch synthesis in a slurry reactor was investigated and a perovskite-type catalyst (LayCu0,4Fe0,6O3 ± d) was used with y varying from 0 to 1 on a molar basis. In addition, Nb2O5 support was also applied in order to observe the selectivity of the produced hydrocarbons by the Fischer-Tropsch process. It is shown that the hydrogen conversion was influenced by the support as well as the different phases of the samples. The kinetic results for the CO2 production suffered great influence with the introduction of the Nb2O5 support throughout the series of samples studied. The catalysts allowed obtaining welldefined cuts of hydrocarbons in the range of C1-C6 and C17-C28, and these results were clearly influenced by the support and the lanthanum content. The higher olefin/paraffin ratio obtained was 1.8 when using a non-supported perovskite with y equal to 0.8. This would indicate the suitability of using this material for the production of olefins

Conversão catalítica de clorometano em hidrocarbonetos

Amorphous silica-alumina and modified by incipient impregnation of iron, nickel, zinc and chromium were synthetized in oxide and metal state and evaluated as catalysts for the chloromethane conversion reaction. With known techniques their textural properties were determined and dynamics techniques in programmed temperature were used to find the acid properties of the materials. A thermodynamic model was used to determine the adsorption and desorption capacity of chloromethane. Two types of reactions were studied. Firstly the chloromethane was catalytically converted to hydrocarbons (T = 300 450 oC e m = 300 mg) in a fixed bed reactor with controlled pressure and flow. Secondly the deactivation of the unmodified support was studied (at 300 °C and m=250 g) in a micro-adsorver provided of gravimetric monitoring. The metal content (2,5%) and the chloromethane percent of the reagent mixture (10% chloromethane in nitrogen) were fixed for all the tests. From the results the chloromethane conversion and selectivity of the gaseous products (H2, CH4, C3 and C4) were determined as well as the energy of desorption (75,2 KJ/mol for Ni/Al2O3-SiO2 to 684 KJ/mol for the Zn/Al2O3-SiO2 catalyst) considering the desorption rate as a temperature function. The presence of a metal on the support showed to have an important significance in the chloromethane condensation. The oxide class catalyst presented a better performance toward the production of hydrocarbons. Especial mention to the ZnO/Al2O3-SiO2 that, in a gas phase basis, produced C3 83 % max. and C4 63% max., respectively, in the temperature of 450 oC and 20 hours on stream. Hydrogen was produced exclusively in the FeO/Al2O3-SiO2 catalysts (15 % max., T = 550 oC and 5,6 h on stream) and Ni/SiO2-Al2O3 (75 % max., T = 400 oC and 21,6 h on stream). All the catalysts produced methane (10 à 92 %), except for Ni/Al2O3-SiO2 and CrO/Al2O3-SiO2. In the deactivation study two models were proposed: The parallel model, where the product production competes with coke formation; and the sequential model, where the coke formation competes with the product desorption dessorption step. With the mass balance equations and the mechanism proposed six parameters were determined. Two kinetic parameters: the hydrocarbon formation constant, 8,46 10-4 min-1, the coke formation, 1,46 10-1 min-1; three thermodynamic constants (the global, 0,003, the chloromethane adsorption 0,417 bar-1, the hydrocarbon adsorption 2,266 bar-1), and the activity exponent of the coke formation (1,516). The model was reasonable well fitted and presented a satisfactory behavior in relation with the proposed mechanism

Integração dos processos de flotação e foto-fenton para redução de óleos e graxas de água produzida em campos de petróleo

During production of oil and gas, there is also the production of an aqueous effluent called produced water. This byproduct has in its composition salts, organic compounds, gases and heavy metals. This research aimed to evaluate the integration of processes Induced Air Flotation (IAF) and photo-Fenton for reducing the Total Oils and Greases (TOG) present in produced water. Experiments were performed with synthetic wastewater prepared from the dispersion of crude oil in saline solution. The system was stirred for 25 min at 33,000 rpm and then allowed to stand for 50 min to allow free oil separation. The initial oil concentration in synthetic wastewater was 300 ppm and 35 ppm for the flotation and the photo-Fenton steps, respectively. These values of initial oil concentration were established based on average values of primary processing units in Potiguar Basin. The processes were studied individually and then the integration was performed considering the best experimental conditions found in each individual step. The separation by flotation showed high removal rate of oil with first-order kinetic behavior. The flotation kinetics was dependent on both the concentration and the hydrophilic-lipophilic balance (HLB) of the surfactant. The best result was obtained for the concentration of 4.06.10-3 mM (k = 0.7719 min-1) of surfactant EO 2, which represents 86% of reduction in TOG after 4 min. For series of surfactants evaluated, the separation efficiency was found to be improved by the use of surfactants with low HLB. Regarding the TOG reduction step by photo-Fenton, the largest oil removal reached was 84% after 45 min of reaction, using 0.44 mM and 10 mM of ferrous ions and hydrogen peroxide, respectively. The best experimental conditions encountered in the integrated process was 10 min of flotation followed by 45 min of photo-Fenton with overall TOG reduction of 99%, which represents 5 ppm of TOG in the treated effluent. The integration of processes flotation and photo-Fenton proved to be highly effective in reducing TOG of produced water in oilfields

Incorporação de resíduo de perfuração em matriz cerâmica: estabilização por solidificação

One of the waste generated during the drilling of oil wells are gravel which are impregnated of drilling fluid. This residue consists of highly toxic chemicals, including toxic metals. This study suggests an alternative process to the treatment of this waste, by incorporating it the form of raw material in the ceramic matrix , and by solidification and stabilize the metals present, Aluminum (Al), Iron (Fe), Manganese (Mn) and Zinc (Zn). The raw materials were characterized by the techniques of X ray fluorescence (FRX), X ray diffraction (DRX), laser granulometry (GL), thermogravimetry (TG) and differential thermal analysis (ADT). To evaluate the percentage of gravel effect the environmental and technological properties were obtained from formulations containing 0, 10 and 20 % by weight of gravel in the ceramic matrix. After sintering at temperatures 1080, 1120 and 1160 °C, the samples were tested for water absorption, the linear shrinkage firing, voltage of rupture and solubility. The results obtained showed that the stabilization by solidification, is a viable alternative to safe disposal of waste drilling. Ceramics products can be used in the manufacture of solid bricks

Concepção e estudo de um biofiltro para tratamento de compostos orgânicos voláteis COVs

In the last decade, biological purification of gaseous waste has become an important alternative to many conventional methods of exhaust air treatment. More recently, biofiltration has proved to be an effective and inexpensive method for the treatment of air contaminated with volatile organic compounds (VOCs). A biofilter consists in a reactor packed with a porous solid bed material, where the microorganisms are fixed. During the biofiltration process, polluted air is transported through the biofilter medium where the contaminant is degraded. Within the biofilm, the pollutants in the waste gases are energy and carbon sources for microbial metabolism and are transformed into CO2, water and biomass. The bed material should be characterized by satisfactory mechanical and physical properties as structure, void fraction, specific area and flow resistance. The aim of this research was the biofilter construction and study of the biological degradation of ethanol and toluene, as well as the modeling of the process. Luffa cylindrica is a brazilian fiber that was used as the filtering material of the present work. The parameters and conditions studied were: composition of nutrients solution; effect of microflorae strains, namely Pseudomanas putida and Rhodococcus rhodochrous; waste gas composition; air flow rate; and inlet load of VOCs. The biofilter operated in diffusion regime and the best results for remotion capacity were obtained when a microorganisms consortion of Pseudomanas putida and Rhodococcus rhodochrous,were used, with a gas flow rate of 1 m3.h-1 and molar ratio nitrogene/phosphore N/P=2 in the nutrients solution. The maximum remotion capacity for ethanol was around 90 g.m-3.h-1 and 50 g.m-3.h-1 to toluene. It was proved that toluene has inhibitory effect on the ethanol remotion When the two VOCs were present in the same waste gas, there was a decrease of 40% in ethanol remotion capacity. Luffa cylindrica does not present considerable pressure drop. Ottengraf and van Lith models were used to represent the results obtained for ethanol and toluene, respectively. The application of the transient model indicated a satisfactory approximation between the experimental results obtained for ethanol and toluene vapors biofiltration and the ones predicted it

Reúso de água no processamento de jeans na indústria têxtil

This study aims to assess the potential for industrial reuse of textile wastewater, after passing through a physical and chemical pretreatment, into denim washing wet processing operations in an industrial textile laundry, with no need for complementary treatments and dilutions. The methodology and evaluation of the proposed tests were based on the production techniques used in the company and upgraded for the experiments tested. The characterization of the treated effluent for 16 selected parameters and the development of a monitoring able to tailor the treated effluent for final disposal in accordance with current legislation was essential for the initiation of testing for reuse. The parameters color, turbidity, SS and pH used were satisfactory as control variables and presents simple determination methods. The denim quality variables considered were: color, odor, appearance and soft handle. The tests were started on a pilot scale following complexity factors attributed to the processes, in denim fabric and jeans, which demonstrated the possibility of reuse, because there was no interference in the processes and at quality of the tested product. Industrial scale tests were initiated by a step control that confirmed the methodology efficiency applied to identify the possibility of reuse by tests that precede each recipe to be processed. 556 replicates were performed in production scale for 47 different recipes of denim washing. The percentage of water reuse was 100% for all processes and repetitions performed after the initial adjustment testing phase. All the jeans were framed with the highest quality for internal control and marketed, being accepted by contractors. The full-scale use of treated wastewater, supported by monitoring and evaluation and control methodology suggested in this study, proved to be valid in textile production, not given any negative impact to the quality the produced jeans under the presented conditions. It is believed that this methodology can be extrapolated to other laundries to determine the possibility of reuse in denim washing wet processing with the necessary modifications to each company.

À luz das inquietas sombras: a criatividade da melancolia na linguagem de Dom Casmurro

Qué se piensa aquí, esencialmente, está a mapear el itinerario de la melancolía creativa en el discurso de Dom Casmurro; es decir, aquél de el cual el valle narrativo de una sensación de la angustia a alçar él él las maneras de la representación en el discurso de Dom Casmurro. El árbol básico en el cual éste estimaba incurre en se basa en el acuerdo de eso que la actual melancolía en el texto del machadiano se puede analizar por las estratagemas de la lengua creativa en la intención de demostrar en él una especie del espacio virtual - el conducir de metáforas, de ironies y del exacerbamento de imágenes - por cuál se prepone el narrador construir su salvación . El propósito es analizar el uso de el proyecto del alegórico y el irónico previstos por el autor en la intención de descubrir pues tales procedimientos contribuyen para crear un texto ese desestabiliza el carácter malsano de la melancolía. Puede propagar lengua creativa de tal manera cuánto otras maneras de la representación de eso las marcas del arte utilizan. Más allá de este traz poético, la contribución de este trabajo también constituye: para componer una escena en la cual el teatralidade de la lengua de Dom Casmurro constituye drama y no tragedia. Después de la pista de los conceptos de los benjaminianas de la melancolía, alegoria, metalenguaje la ironía, vimos que éstos disalign de la voluntad que los estatutos se estabilizaron de las figuras del retórico para consistir mientras que las estrategias de los discursivas. Subyacente a este proceso es posible percibir el flash del rescate de la escritura melancholic, visto bajo luz del saturnine de una mirada que si desea alegórico, en la misma incandescencia de la risa del fáustico