607 resultados para reaproveitamento de subprodutos
Resumo:
A siderurgia vem sofrendo transformações que buscam inovação e matérias-primas alternativas. Dentro deste contexto, o uso de resíduos industriais para a formação de escórias sintéticas é tido como alternativa na busca de novos materiais e rotas de reaproveitamento de resíduos. Portanto, este trabalho teve como objetivo estudar o uso de escórias sintéticas na etapa de dessulfuração do ferro-gusa, aço e ferro fundido. Assim como, propor a utilização da sodalita e da alumina em substituição à fluorita e o resíduo de mármore em substituição à cal convencional. Inicialmente, o resíduo foi caracterizado utilizando as seguintes técnicas: análise química, análise granulométrica, área de superfície específica, difração de raios-X, microscopia eletrônica de varredura (MEV) e análise de espectroscopia por energia dispersiva (EDS). Os resultados da caracterização mostraram que aproximadamente 90% das partículas do resíduo de mármore estão abaixo de 100m e sua área superficial foi de 0,24m²/g. Através da difração de raios-X foi observado que o resíduo é composto por CaCO3, MgCO3 e SiO2. Na sequência, foram feitas simulações com o software Thermo-Calc para obter dados termodinâmicos das fases presentes nas misturas e compará-los com os resultados experimentais. Além disso, também foram calculados dados de capacidade de sulfeto (Cs), partição de enxofre (Ls) e basicidade ótica () das misturas iniciais. Posteriormente, foram realizados os ensaios experimentais em escala laboratorial para ferro-gusa, ferro fundido e aço, respectivamente nas temperaturas de 1400°C, 1550°C e 1600°C. Nos ensaios de dessulfuração do aço e do ferro-gusa, utilizou-se um rotor de alumina com o objetivo de favorecer a agitação no metal e aumentar a remoção de enxofre. Na etapa de dessulfuração do ferro-gusa, constatou-se que a fase sólida de CaO é a responsável pela remoção de enxofre e que a presença das fases silicato tricálcio e aluminato tricálcio (3CaO.SiO2 e 3CaO.Al2O3) limitam a reação, sendo maiores suas concentrações nas escórias que utilizaram o resíduo de mármore e sodalita, devido a presença de SiO2 e Al2O3 nestas matérias-primas. Já para o aço e o ferro fundido, que foram estudados com escórias à base de CaO e Al2O3, observou-se que o aumento da fase líquida favoreceu a dessulfuração. Verificou-se que a dessulfuração no ferro fundido foi por escória de topo e no aço por um processo misto, onde a fase líquida e fase sólida participaram da dessulfuração.
Resumo:
Com objectivo de melhorar a qualidade da carne de origem caprina e ovina proveniente de animais adultos de raças Serrana e Churra Galega Bragançana (CGB), de forma a atribuir-lhe um valor comercial acrescentado, foram elaborados diferentes tipos de patês com incorporação de diferentes níveis de gordura de porco. O estudo foi feito no laboratório de Tecnologias de Qualidade da Carcaça e da Carne da Escola Superior Agrária, do Instituto Politécnico de Bragança. Os patês foram submetidos a uma avaliação da qualidade físico-química no período de um ano como forma de estudar a vida útil dos mesmos, quando conservados à temperatura de 2 a 4º C. As determinações físico-químicas foram repetidas quatro vezes em cada período de estudo, nomeadamente 1, 6 e 12 meses de conservação. Diferenças entre as médias foram consideradas estatisticamente significantes, no nível de 5%, quando p ≤ 0,05. O tratamento estatístico dos dados foi realizado utilizando o programa Statistix 10. A transformação de carne de animais adultos em subprodutos originou patês de alto valor nutricional, com vida útil superior a um ano. Com a avaliação do pH em patês de ambas espécies, foi possível observar maior queda de pH em patês de origem caprina, podendo-se afirmar que os mesmos têm baixa estabilidade quando comparados com os de origem ovina. A incorporação de gordura de porco, proveniente de abdómen, influenciou positivamente na qualidade físico-química do produto final. Patês com incorporação de gordura de porco apresentaram maior teor de ácidos gordos saturados e poli-insaturados. Em relação às duas espécies, as amostras de patês de origem ovina sem incorporação de gordura de porco apresentaram maior teor de gordura saturada e menor teor de gordura mono-insaturada.
Resumo:
O setor sucroalcooleiro se destaca no âmbito social devido à empregabilidade de projetos sociais e a inclusão social dos diversos atores pertencentes à cadeia produtiva da cana-de-açúcar. No campo econômico, sua importância se deve à renda per capita dos municípios onde estão localizadas as usinas e as divisas geradas para o país a partir do saldo da balança comercial da exportação açúcar e álcool. Entretanto, na esfera ambiental, diante do alto índice de poluição causada pela origem de resíduo, liberação de gases na atmosfera e desmatamento, o setor já não desfruta do mesmo destaque. Desta forma, o presente artigo tem como objetivo apresentar as ações de uma usina de álcool, a Pioneiros Bioenergia S/A, com relação ao tratamento de vinhaça que é um resíduo altamente poluente do meio ambiente. Para atingir o propósito deste foi realizada uma pesquisa qualitativa em uma empresa do setor sucroalcooleiro com utilização de aparatos da abordagem estratégica da Visão Baseada em Recursos (VBR) e da Inovação Sustentável. Verifica-se que a empregabilidade da vinhaça no processo de fertirrigação ou adubação orgânica é uma inovação que vem ao encontro da questão ambiental e possibilita a usina a se tornar sustentável, pois aloca e reutiliza corretamente produtos ou subprodutos que poderiam causar impactos ao meio ambiente ou que antes era descartado dentro da empresa. Todavia, mesmo servindo como modelo, o processo ambiental na Pioneiros ainda pode ser melhorado, principalmente na questão de maiores investimentos para expandir o uso da vinhaça em outras inovações de cunho sustentável.
Otimização da síntese do AlSBA-15 para produção de biodiesel por transesteri-ficação do óleo de coco
Resumo:
Stimulus encouraging the production and consumption of biodiesel favors the policy of pre-serving the environment, contributing to the reduction of greenhouse gas reducing climate change. The current trend of research in this field focuses on improving these processes with the use of heterogeneous catalysts, seeing has significant advantages such as: low contamination of products, ease of separation of the catalyst from the reaction medium, possibili-ty of reuse of the catalyst, decreased corrosion problems. The objective of this research was to optimize the synthesis of AlSBA-15 for the production of biodiesel through transesterification process via ethyl route. For the optimization of hydrothermal synthesis of type AlSBA-15 catalyst has assembled a 23 factorial experimental matrix with eleven trials. The stoichiometric amounts of starting materials were varied according to different ratios Si / Al which is a factor in the experimental design, in addition to the time and temperature of aging of the synthesis gel. The material showed the best results of characterization (SBET = 591.7 (m2 / g), Vp = 0.83 (cm3 / g), Dp = 5.59 (nm), w = 6.48 (nm) was synthesized at 100 ° C for 24 hours, with a ratio Si / Al = 10.This material was applied as a heterogeneous catalyst in the reaction of ethyl transesterification as raw coconut oil in natura. Coconut oil presented suitable for obtaining biodiesel via ethyl route.The visual aspects and physical-chemical characteristics of the reaction products show that AlSBA-15 catalyst favored the reaction. According to physical-chemical analysis the order of oxidative stability of the product of the transesterification reaction was: catalytic reaction at 1500 ° C> non-catalytic reaction at 100 ° C> 100 ° C catalytic> catalytic reaction at 200 ° C Reaction. The results of oxidative stability and kinematic viscosity shows that the biodiesel produced in the catalytic sandblasting held at 150 ° C which was maintained within the ABNT NBR 7148, ABNT NBR 10441 and EN 14112.
Resumo:
Prospecting pharmacological active polysaccharides from agricultural byproducts, such as corncobs, is an underexplored practice in the scientific community. Thus, this work aims to expand knowledge about pharmacological activities of polysaccharides extracted from corncobs. From corn cob flour a extract was obtained by ultrasound waves in an alkaline medium, and the end of the process the product was termed PECC (polysaccharidic extract from corncobs). This extract was physicochemical characterized and evaluated by in vitro assays as an antioxidant, cytotoxic, anticoagulant and imunomodulator agent. Results indicated significant activity metal chelating by PECC, and the use of PECC in cell culture cells showed no toxic effects to normal cell lines, but toxic action against HeLa tumor cells due promoting cell death by apoptosis. In addition, other pharmacological effects were observed, the PECC decreased nitric oxide (NO) production by activated macrophages, and prolonged blood clotting time through APTT assay. Then methanolic, ethanolic and ketone fractions were obtained from fractionation of PECC polysaccharides. Five methanolic fractions, six ethanolic fractions and two ketones were obtained; and all fractions were evaluated for antioxidant, cytotoxic, anticoagulant, immunomodulatory activities. E1.4 fraction exhibited significant metal chelating effect, a toxic action to induce apoptosis in HeLa cells, decreased NO production by activated macrophages, and extended blood clotting time. These results showed that the PECC pharmacological active polysaccharides would be present in the fraction E1.4. From fractionation of E1.4 polysaccharide six subfractions with different sizes were obtained: <3; 3-10; 10-30; 30-50; 50-100 and >100 KDa. About 80% of E1.4 polysaccharides had lower size to 10 KDa, and all the subfractions showed over 61% sugar in their chemical compositions. These subfractions exhibited different monosaccharide compositions, but xylose was presented in all of them. The subfractions exhibited distinct pharmacological effects in in vitro assays. Smaller subfractions (<30 KDa) had highest metal chelating activity and greater toxic action in tumor cells. The intermediate fractions (between 30-100 KDa) decreased more NO production of activated macrophages, for other side, the larger size (>100 KDa) modulated a greater number of inflammatory cytokines, and the had greatest anticoagulant effect. Therefore, when analyzing all the results together it is evident that the PECC pharmacological polysaccharides are heteroxylans, and were concentrated in E1.4 fraction, and heteroxilanas pharmacological effects depends on their molecular size. Thus, corncobs could be used as source from molecules with biotechnology potential
Resumo:
During the drilling of oil and natural gas are generated solid waste, liquid and gaseous. These solid fragments, which are known as cuttings, are carried to the surface through the drilling fluid. Furthermore, this fluid serves to cool the bit, keeping the internal pressure of the well, and others. This solid residue is very polluting, because it has incorporated beyond the drilling fluid, which has several chemical additives harmful to the environment, some heavy metals that are harmful to the environment, such as lead. To minimize the residue generated, are currently being studied numerous techniques to mitigate the problems that such waste can cause to the environment, like addition of cuttings in the composition of soil cement brick masonry construction, addition of cuttings on the clay matrix for the manufacture of solid masonry bricks and ceramic blocks and coprocessing of the cuttings in cement. So, the main objective of this work is the incorporation of cuttings drilling of oil wells, the cement slurry used in the cementing operation of the well. This cuttings used in this study, arising from the formation Pendências, was milled and separated in a sieve of 100 mesh. After grinding had a mean particle sike in order of 86 mm and crystal structure containing phases of quartz and calcite type, characteristic of the Portland cement. Were formulated and prepared slurries of cement with density 13 lb / gal, containing different concentrations of gravel, and realized characterization tests API SPEC 10A and RP 10B. Free water tests showed values lower than 5.9% and the rheological model that best described the behavior of the mixtures was the power. The results of compressive strength (10.3 MPa) and stability (Dr <0.5 lb / gal) had values within the set of operational procedures. Thus, the gravel from the drilling operation, may be used as binders in addition to Portland cement oil wells, in order to reuse this waste and reduce the cost of the cement paste.
Resumo:
The sugarcane production consists in the principal product activity in the state of Alagoas, holding a structure composed of 25 unities of production that represents the economic base of more than a half of its municipies, what make it be the biggest producer of the sector in North and Northwest, exporting its products for countries in different continents. From this reference, it was searched in the present work, to understand the configuration of the circuit space production of sugar cane in Alagoas, from the use of the territory, trough the analyses of the more significant events related to the sector, and, the established rules by the State, through the government, by organs like Institute of Sugar and Alcohol (IAA), and programs like National Alcohol Program (Proálcool), between others, that had as function to structure and to allocate resources to the sugar cane sector. It was realized that the investments done made possible the renovation of techniques used in the sugar cane complex. In the beginning, with the substitution of the mill for factories and, afterwards, the improvement of the agriculture and factory process themselves, improving the utilization of the byproduct, and the productive integration of instances, specially with the sugar, cane, electricity generation production, intensifying the participation of the state in the internation division of labor, giving it a organization structure divided by big hegemonic agents of this process. SO, the sugar cane geographic configuration existing in alagoano territory was restructured and the circuit even more pass to constitute movement of many scales, subsidized by cooperation circles. However, this configuration showed itself subservient to world commerce, what conditions the adoption of hegemonic practices that are far from the local projects and living practices. The verticality imposed offers a configuration that isn’t peculiar, that only serves to answer to the big hegemonic agent commands, characterizing the continuity of the present capitalism process. It means that the sugar cane factories use corporately the territory as resource to obtain more lucrativity and this way dominate the bigger quantity of consumer commerce
Resumo:
The water supply and treatment is considered as a great benefit considering that, if done efficiently, provides public health. However, considering the WTP (Water Treatment Plant) is an industry, with its inputs and waste generation, they must be constantly evaluated and monitored to verify the best and most appropriate way to process and dispose their waste, minimizing therefore the potential impacts to the environment. By volume, the most significant waste is the rapid filter backwash water. It is very common the disposal of this waste without treatment in water sources, which are used, for the most part, as a water supply source of a downstream population. This study evaluated quantitative and qualitative parameters in filter backwash water in three WTP - Itaitinga, Maranguape and Pacatuba, located in Ceará State, northeast of Brazil. It was found that the Maranguape WTP, in terms of treatment capacity, is the larger. The Itaitinga WTP is the one that consumes more water during filters washing. The Pacatuba WTP exhibited higher concentration of total suspended and settleable solids, COD and aluminum in the filters backwash water. It is noteworthy that the settleable solids and total suspended solids in all three WTP are above the effluent discharge standard recommended by Resolution 154/2002 of SEMACE (State Superintendent of Environment of Ceará). It was concluded that the filter backwash water from the study WTP exceeded the allowed values for legislation to be disposed directly into surface water bodies. It is suggested as an alternative to treat and recycle the filter backwashing water the construction of sludge settling ponds.
Resumo:
The contamination of water bodies with toxic substances causes a decrease in water quality, representing a risk to public health. In this context, human activities are generally seen as the main sources of water degradation. However, elements found naturally in the environment can also compromise water quality. Thus, the Boqueirão‘s dam, located in the municipality of Parelhas (RN, Brazil), was chosen as area for the development of this study, as its geological region is rich in the emission of natural ionizing radiation that produces byproducts like lead and Radon. Moreover, the area has a strong human influence that enhances the risks of pollutant discharge in this body of water.Thus, the objectives of this study were centered (i) in the analysis of risk perception in the city of Parelhas (RN/Brasil) due to the use of the water from the Boqueirão Dam; and (ii) in the assessment of water quality in the Dam using methods that quantify, mainly, heavy metals and radiation levels, as well as these toxics potential of inducing mutations on genetic material. The analysis of risk perception showed that the population in the city of Parelhas can perceive a risk in using the water from the dam and that they can recognize factors that influence the water quality. Regarding the second objective, the set of data point to the contamination of the Dam by heavy metals, as well as levels of radioactive parcicles and Radon – also present in high concentrations in outdoor air and on soil. Thus, it is possible to infer that the population residing in this area is subjected to injuries caused by exposure to natural and anthropogenic contamination. Our findings corroborate with the perception of the population regarding the risks associated with the use of the Dam for several types of activities. It is expected that the information gathered in this study can substantiate activities and future researches in this semiarid region in the Rio Grande do Norte/Brazil. Also, that the set of data can enable a better understanding of the specific toxicological scenario of risk found for the population and the effect of the contamination for the biota, which aids the development of a future risk assessment and a consequent management of this local issue.
Resumo:
This research is presented as a comparative study about the baking capacity of two box type ovens, produced from a packing case used to equipment transportation. The two ovens have different internal settings, with the greenhouse effect and the concentration of incident solar radiation as the main parameters of differentiation. The main features of the ovens are the low cost, the reuse of materials, the manufacturing and assembly processes simplified, the easy management and the ability of baking a variety of foods simultaneously. The manufacturing and operation of the ovens can be handled by any social and intellectual level of people. The feasibility of the ovens to bake the tested foods was proved with success, ensuring the supremacy of the mirrored oven. The results obtained for both ovens were competitive even with the conventional gas oven, producing the baking of three cakes with 750g in just 80 minutes.
Resumo:
The treatment of wastewater is essential to human health. One of the most important steps is the disinfection treatment which uses chlorine to eliminate bacteria as required by environmental agencies. However, the identification of potentially toxic byproducts generated by this method, such as trihalomethanes, has stimulated the development of new alternative disinfection technologies. Among them, heterogeneous photocatalysis, TiO2 photocatalysis and electrochemical disinfection are considered suitable alternatives to the chlorination method. Thus, the present dissertation analyzes the evolution of active chlorine species in a synthetic NaCl solution and it is tested to treat a synthetic solution of the dye Reactive Blue 19 using boron-doped diamond (BDD) and ruthenium oxide (Ti/Ru0.3Ti0.7O2) as anodes. The indirect electrochemical process was discussed in terms of mineralization of the total organic load and percentage of color removal in order to evaluate the applicability of electrochemical technology. Electrochemical experiments were carried out with different current densities (25, 50 and 75 mA.cm-2) during 120 minutes. On the other hand, other important parameter in this study was the influence of the proportion sp3/sp2 on BDD anode on the performance of the evolution of active chlorine species which was investigated by electrolytic techniques (linear polarization), with the intention of determining the related training oxidizing species and consumption energy to chemical or electrochemical reactions. From the results, it can be noted that the BDD electrode showed better efficiency throughout the electrochemical process.
Resumo:
The treatment of wastewater is essential to human health. One of the most important steps is the disinfection treatment which uses chlorine to eliminate bacteria as required by environmental agencies. However, the identification of potentially toxic byproducts generated by this method, such as trihalomethanes, has stimulated the development of new alternative disinfection technologies. Among them, heterogeneous photocatalysis, TiO2 photocatalysis and electrochemical disinfection are considered suitable alternatives to the chlorination method. Thus, the present dissertation analyzes the evolution of active chlorine species in a synthetic NaCl solution and it is tested to treat a synthetic solution of the dye Reactive Blue 19 using boron-doped diamond (BDD) and ruthenium oxide (Ti/Ru0.3Ti0.7O2) as anodes. The indirect electrochemical process was discussed in terms of mineralization of the total organic load and percentage of color removal in order to evaluate the applicability of electrochemical technology. Electrochemical experiments were carried out with different current densities (25, 50 and 75 mA.cm-2) during 120 minutes. On the other hand, other important parameter in this study was the influence of the proportion sp3/sp2 on BDD anode on the performance of the evolution of active chlorine species which was investigated by electrolytic techniques (linear polarization), with the intention of determining the related training oxidizing species and consumption energy to chemical or electrochemical reactions. From the results, it can be noted that the BDD electrode showed better efficiency throughout the electrochemical process.
Resumo:
The monoaromatic compounds are toxic substances present in petroleum derivades and used broadly in the chemical and petrochemical industries. Those compounds are continuously released into the environment, contaminating the soil and water sources, leading to the possible unfeasibility of those hydrous resources due to their highly carcinogenic and mutagenic potentiality, since even in low concentrations, the BTEX may cause serious health issues. Therefore, it is extremely important to develop and search for new methodologies that assist and enable the treatment of BTEX-contaminated matrix. The bioremediation consists on the utilization of microbial groups capable of degrading hydrocarbons, promoting mineralization, or in other words, the permanent destruction of residues, eliminating the risks of future contaminations. This work investigated the biodegradation kinetics of water-soluble monoaromatic compounds (benzene, toluene and ethylbenzene), based on the evaluation of its consummation by the Pseudomonas aeruginosa bacteria, for concentrations varying from 40 to 200 mg/L. To do so, the performances of Monod kinetic model for microbial growth were evaluated and the material balance equations for a batch operation were discretized and numerically solved by the fourth order Runge-Kutta method. The kinetic parameters obtained using the method of least squares as statistical criteria were coherent when compared to those obtained from the literature. They also showed that, the microorganism has greater affinity for ethylbenzene. That way, it was possible to observe that Monod model can predict the experimental data for the individual biodegradation of the BTEX substrates and it can be applied to the optimization of the biodegradation processes of toxic compounds for different types of bioreactors and for different operational conditions.
Resumo:
The monoaromatic compounds are toxic substances present in petroleum derivades and used broadly in the chemical and petrochemical industries. Those compounds are continuously released into the environment, contaminating the soil and water sources, leading to the possible unfeasibility of those hydrous resources due to their highly carcinogenic and mutagenic potentiality, since even in low concentrations, the BTEX may cause serious health issues. Therefore, it is extremely important to develop and search for new methodologies that assist and enable the treatment of BTEX-contaminated matrix. The bioremediation consists on the utilization of microbial groups capable of degrading hydrocarbons, promoting mineralization, or in other words, the permanent destruction of residues, eliminating the risks of future contaminations. This work investigated the biodegradation kinetics of water-soluble monoaromatic compounds (benzene, toluene and ethylbenzene), based on the evaluation of its consummation by the Pseudomonas aeruginosa bacteria, for concentrations varying from 40 to 200 mg/L. To do so, the performances of Monod kinetic model for microbial growth were evaluated and the material balance equations for a batch operation were discretized and numerically solved by the fourth order Runge-Kutta method. The kinetic parameters obtained using the method of least squares as statistical criteria were coherent when compared to those obtained from the literature. They also showed that, the microorganism has greater affinity for ethylbenzene. That way, it was possible to observe that Monod model can predict the experimental data for the individual biodegradation of the BTEX substrates and it can be applied to the optimization of the biodegradation processes of toxic compounds for different types of bioreactors and for different operational conditions.
Resumo:
Oil exploration is one of the most important industrial activities of modern society. Despite its derivatives present numerous applications in industrial processes, there are many undesirable by-products during this process, one of them is water separated from oil, called water production, it is constituted by pollutants difficult to degrade. In addition, the high volume of generated water makes its treatment a major problem for oil industries. Among the major contaminants of such effluents are phenol and its derivatives, substances of difficult natural degradation, which due their toxicity must be removed by a treatment process before its final disposal. In order to facilitate the removal of phenol in wastedwater from oil industry, it was developed an extraction system by ionic flocculation with surfactant. The ionic flocculation relies on the reaction of carboxylate surfactant and calcium íons, yielding in an insoluble surfactant that under stirring, aggregates forming floc capable of attracting the organic matter by adsorption. In this work was used base soap as ionic surfactant in the flocculation process and evaluated phenol removal efficiency in relation to the following parameters: surfactant concentration, phenol, calcium and electrolytes, stirring speed, contact time, temperature and pH. The flocculation of the surfactant occurred in the effluent (initial phenol concentration = 100 ppm) reaching 65% of phenol removal to concentrations of 1300 ppm and calcium of 1000 ppm, respectively, at T = 35 °C, pH = 9.7, stirring rate = 100 rpm and contact time of 5 minutes. The permanence of the flocs in an aqueous medium promotes desorption of the phenol from the flake surface to the solution, reaching 90% of desorption at a time of 150 minutes, and the study of desorption kinetics showed that Lagergren model of pseudo-first order was adequate to describe the phenol desorption. These results shows that the process may configure a new alternative of treatment in regard the removal of phenol of aqueous effluent of oil industry.