Bio-óleo e biogás da degradação termoquímica de lodo de esgoto doméstico em cilindro rotativo

The objective of this study was to produce biofuels (bio-oil and gas) from the thermal treatment of sewage sludge in rotating cylinder, aiming industrial applications. The biomass was characterized by immediate and instrumental analysis (elemental analysis, scanning electron microscopy - SEM, X-ray diffraction, infrared spectroscopy and ICP-OES). A kinetic study on non-stationary regime was done to calculate the activation energy by Thermal Gravimetric Analysis evaluating thermochemical and thermocatalytic process of sludge, the latter being in the presence of USY zeolite. As expected, the activation energy evaluated by the mathematical model "Model-free kinetics" applying techniques isoconversionais was lowest for the catalytic tests (57.9 to 108.9 kJ/mol in the range of biomass conversion of 40 to 80%). The pyrolytic plant at a laboratory scale reactor consists of a rotating cylinder whose length is 100 cm with capable of processing up to 1 kg biomass/h. In the process of pyrolysis thermochemical were studied following parameters: temperature of reaction (500 to 600 ° C), flow rate of carrier gas (50 to 200 mL/min), frequency of rotation of centrifugation for condensation of bio-oil (20 to 30 Hz) and flow of biomass (4 and 22 g/min). Products obtained during the process (pyrolytic liquid, coal and gas) were characterized by classical and instrumental analytical techniques. The maximum yield of liquid pyrolytic was approximately 10.5% obtained in the conditions of temperature of 500 °C, centrifugation speed of 20 Hz, an inert gas flow of 200 mL/min and feeding of biomass 22 g/min. The highest yield obtained for the gas phase was 23.3% for the temperature of 600 °C, flow rate of 200 mL/min inert, frequency of rotation of the column of vapor condensation 30 Hz and flow of biomass of 22 g/min. The non-oxygenated aliphatic hydrocarbons were found in greater proportion in the bio-oil (55%) followed by aliphatic oxygenated (27%). The bio-oil had the following characteristics: pH 6.81, density between 1.05 and 1.09 g/mL, viscosity between 2.5 and 3.1 cSt and highest heating value between 16.91 and 17.85 MJ/ kg. The main components in the gas phase were: H2, CO, CO2 and CH4. Hydrogen was the main constituent of the gas mixture, with a yield of about 46.2% for a temperature of 600 ° C. Among the hydrocarbons formed, methane was found in higher yield (16.6%) for the temperature 520 oC. The solid phase obtained showed a high ash content (70%) due to the abundant presence of metals in coal, in particular iron, which was also present in bio-oil with a rate of 0.068% in the test performed at a temperature of 500 oC.

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

Estudo dos óxidos A2B2O7 e ABO3 a base de terras raras, para aplicações térmicas e catalíticas a altas temperaturas

Rare earth elements have recently been involved in a range of advanced technologies like microelectronics, membranes for catalytic conversion and applications in gas sensors. In the family of rare earth elements like cerium can play a key role in such industrial applications. However, the high cost of these materials and the control and efficiencies associated processes required for its use in advanced technologies, are a permanent obstacle to its industrial development. In present study was proposed the creation of phases based on rare earth elements that can be used because of its thermal behavior, ionic conduction and catalytic properties. This way were studied two types of structure (ABO3 and A2B2O7), the basis of rare earths, observing their transport properties of ionic and electronic, as well as their catalytic applications in the treatment of methane. For the process of obtaining the first structure, a new synthesis method based on the use of EDTA citrate mixture was used to develop a precursor, which undergone heat treatment at 950 ° C resulted in the development of submicron phase BaCeO3 powders. The catalytic activity of perovskite begins at 450 ° C to achieve complete conversion at 675 ° C, where at this temperature, the catalytic efficiency of the phase is maximum. The evolution of conductivity with temperature for the perovskite phase revealed a series of electrical changes strongly correlated with structural transitions known in the literature. Finally, we can establish a real correlation between the high catalytic activity observed around the temperature of 650 ° C and increasing the oxygen ionic conductivity. For the second structure, showed clearly that it is possible, through chemical processes optimized to separate the rare earth elements and synthesize a pyrochlore phase TR2Ce2O7 particular formula. This "extracted phase" can be obtained directly at low cost, based on complex systems made of natural minerals and tailings, such as monazite. Moreover, this method is applied to matters of "no cost", which is the case of waste, making a preparation method of phases useful for high technology applications

Evolução da biodegradabilidade da matéria orgânica em um sistema de lagoas de estabilização

Waste stabilization ponds (WSP) have been widely used for sewage treatment in hot climate regions because they are economic and environmentally sustainable. In the present study a WSP complex comprising a primary facultative pond (PFP) followed by two maturation ponds (MP-1 and MP-2) was studied, in the city of Natal-RN. The main objective was to study the bio-degradability of organic matter through the determination of the kinetic constant k throughout the system. The work was carried out in two phases. In the first, the variability in BOD, COD and TOC concentrations and an analysis of the relations between these parameters, in the influent raw sewage, pond effluents and in specific areas inside the ponds was studied. In the second stage, the decay rate for organic matter (k) was determined throughout the system based on BOD tests on the influent sewage, pond effluents and water column samples taken from fixed locations within the ponds, using the mathematical methods of Least Squares and the Thomas equation. Subsequently k was estimated as a function of a hydrodynamic model determined from the dispersion number (d), using empirical methods and a Partial Hydrodynamic Evaluation (PHE), obtained from tracer studies in a section of the primary facultative pond corresponding to 10% of its total length. The concentrations of biodegradable organic matter, measured as BOD and COD, gradually reduced through the series of ponds, giving overall removal efficiencies of 71.95% for BOD and of 52.45% for COD. Determining the values for k, in the influent and effluent samples of the ponds using the mathematical method of Least Squares, gave the following values respectively: primary facultative pond (0,23 day-1 and 0,09 day-1), maturation 1 (0,04 day-1 and 0,03 day-1) and maturation 2 (0,03 day-1 and 0,08 day-1). When using the Thomas method, the values of k in the influents and effluents of the ponds were: primary facultative pond (0,17 day-1 and 0,07 day-1), maturation 1 (0,02 day-1 and 0,01 day-1) and maturation 2 (0,01 day-1 and 0,02 day-1). From the Partial Hydrodynamic Evaluation, in the first section of the facultative pond corresponding to 10% of its total length, it can be concluded from the dispersion number obtained of d = 0.04, that the hydraulic regime is one of dispersed flow with a kinetic constant value of 0.20 day-1

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

João Cabral de Melo Neto: a estética do avesso

La pieza-poema Morte e Vida severina Auto de natal pernambucano, de João Cabral de Melo Neto, publicada en 1956, es el principal objeto de este estudio, interaccionando con las obras O Cão sem plumas y O rio por la similitud temática entre ellas: el estudio sobre esas obras busca una lectura desvinculada del posicionamiento constructivista y metalingüístico que por tradición configura la obra cabralina, no por negar a la crítica literaria que da respaldo científico, pero con la pretensión de lanzar una nueva mirada dirigida para el concepto de barroco, materia ésta que implica la creación poética a partir de la segunda mitad del siglo XX. Por lo tanto, este trabajo presenta una propuesta de análisis de la poesía de João Cabral a partir del contexto neobarroco. Considerando, sobre todo, los aspectos similares a la temática del barroco, el enfoque recae sobre la influencia de la literatura ibérica por que pasa el poeta João Cabral, así como la temática sobre el conflicto existencial explorado en el texto Morte e Vida severina, y aún, los extractos de lenguaje con significación múltiple que presentan signos metonímicos y metafóricos.

A doença de criar passarinhos: a lírica humanizadora de João Cabral de Melo Neto

João Cabral de Melo Neto n a jamais aimé les vers sentimentaux et prolixes venus de la tradition romantique. C est pour ça que son uvre a un discours objectif, rigoureusement elaboré e elle comporte certaines influences concretistes ça explique pourquoi l auteur est connu comme l ingénieur de la langage. En verité, le poète même dissait qu il était un homme froid et rationnel. La critique a assidument analysé la matière logique et le rigeuer formel de l uvre de Cabral de Melo. Pourtant, dans ce travail nous analysons les poèmes dont le sentiments humaines sont la mtière principal de l élaboration de l experiènce esthétique. La poèsie de João Cabral n est pas simple verbalisme formel, ni un uvre sens vie, car les objects concrètes et la langage objectif n empêchent pas qui le sujet décrit avec émotion les scènes presents dans les poèmes. Nous travaillons avec la hypothèse de que le poète a une attitude trop humaine quand il parle de l experience culturel et de l experience de la vie dans le Nord-est brésilien. Les unités témathiques de ce travail, pourtant, montrent la représentation du Nord-est dans la poèsie de João Cabral et examinent aussi le sentiment qu il sent par la memoire culturel de sa région. Parmi les aspects qui composent sa lyrique humaine nous citons la personification constant de les paysages du Nord-est le poète ne veux pas faire une décrition tophographique de la région parce que les places ont un valeuer sentimentel pour lui; au moyen d un discours erotique, Cabral represente les desirs et les intints humaines de sa terre; ensuite, il semble que le poète est enchanté et enveloppé avec certains elemets culturels de sa région, come l hamac, la littérature oral et la musique régional; la preoccupation avec la population explorée et la denonciation de la condition miserable dans le Nord-est brésilien confirment aussi la humanité présent dans son uvre; finalment, la récordation de l enfance et la nostalgie du temps passé sont, pour le poète, un possibilité qui peut aider dans la formation humaine de la population

O significado dos símbolos e dos signos de noites do sertão

Les symboles et les signes de Noites do Sertão, de João Guimarães Rosa, contient l étude d une édition de cette ouvrage, publié par Livraria José Olímpio Editora, en 1975. Un éditeur arrêtée. Notre priorité c est montrer au lecteur les dégradations résultants d altérations ou d omissions qu on vérifie dans les publications postérieurs; d une manière spécifique, les éditions mais récents. Dans le primiere chapitre, notre recherche privilégie l analyse et l explication de las inscirtions qui sons enregistré dans la partie exterior, ou dans la couverture de ce livre. Le deuxième chapitre traite des réflexions sur ce qui se réfère au revers de la couverture, dans le côté gauche: les énigmes dont l auteur utilise avec l intention de bien idiquer au lecteur orientations pour envisager les aspects des narratives. Combien, nous méditerons ici sur la signification des épigraphes de cette ouvrage; sur les noms des personnages les plus importants et sur la connexion de ce livre avec autres textes littéraires. Dans le troisième chapitre nous explicitons la rélation de contiguïté avec cette ouvrage et le platonisme. O Chapitre quatre s occupe d étudier toutes cettes symboles vérifier ici sur la pérspective de la vision Junguienne (C.G.Jung); et dans le cinq, analysons les relations possibles de cette ouvrage avec autres livres du même écriteur. Finalement, nous présentons un vocabulaire qui est très importants pour la compréhention des mots mais compliqué dans ce texte écrit pour João Guimarães Rosa

Das margens do espelho: um estudo dos reflexos da morte em primeiras estórias, de João Guimarães Rosa

This paper is divided into three chapters, which are structured as follows: in the first chapter, we examine the figure of death and its characteristics in the context of the work of Guimarães Rosa, within a specific type, determining how this figure comes through " imposition "," no "," memory "and" ritual. " We intend to cover all the possibilities that this aspect denotes. In the second chapter, we found the incidence of the mirror as an analysis of our study, characterizing it as a stylistic condition can become a reading key, necessary for interpretation of the book "First Stories". The characterization of the mirror as an element of analysis has a theoretical foundation which stretches out along other literary works that are based on the same object. By setting the points where these works approach the theories of speculation, we want to justify their use from our perspective

O auto da morte e da vida : a escrita barroca de João Cabral de Melo Neto

This dissertation, entitled O Auto da Morte e da Vida: A escrita barroca de João Cabral de Melo Neto, has the aim of analising, interpreting, in a baroque perspective, Cabral s writing in the poem/play Morte e vida severina Auto de Natal Pernambucano, taking as basis the theories of Eugênio D´Ors, Severo Sarduy, Omar Calabrase, Lezama Lima, Afonso Ávila, Affonso Romano de Sant´Anna and others cited in the body of this work. During the analisys we feature confluences, relations, similarities, identification between the Baroque of the counter reformation and the modern Baroque or Neobaroque. We seek to comprehend the baroque which is new in the XX century and Cabral s poetry as an element of the contemporaneity, by updating the concept of the Baroque in the 1600s, when it is detected in its purest characteristic in human relation (the life of the Northwestern brazilian) through an intangible reality (the death). The Baroque as a cultural summary of a period of instability and transformation, with the power of dismantling an already established poetry. The fight between words and things, language and reality

Resistência e performance na arte de João Cota

Researching about the art of tell and the tales told by João Cota is somehow revisiting the oral tradition and social practice in the story-telling art. It takes into consideration the resistance this art still exerts, mainly by using the performance of oral transmission and receptiveness to tales. The study of this practice contributes to the vivacious and dynamcis permanence of this authentic and traditional storyteller of his repertory and of his form to tellin our culture. Story-telling is part of the humankind living heritage communicated by means of popular wisdom. Despite the risk of vanishing into thin air, along with their narrators, the tales still manage to resist the contemporary mass culture model. How long further will stories like the ones narrated by João Cota be able to resist to strong and stronger structures dictated by writing and other communication means? João Cota s practice in story-telling will be studied not only as a proposal to identify the presence of this practice and the oral cultural resistance but also, through the performance prospective, to identify the oral transmission and receptiveness to the tales that are part of this storyteller s repertoire. In other words: what he tells, how he tells it, and why he tells it. The advent of new technologies such as internet, through which people can easily communicate with others in different parts of the world, and the greater and greater expansion in the writing skill concept interfere the maintenance of the oral tradition elements present in João Cota s narratives and inserted in the Brazilian culture. This has become more visible in the latest decades although we still notice the living tradition and permanence of the story-telling practice in several parts of the country through their wise storytellers. Our research target will require - in each of its study stages reference to works by several theoreticians namely Paul Zumthor, Mikhail Bakhtin, Câmara Cascudo, theoreticians from the receptiveness aesthetic, from the written culture history, from oral cultures and reading practices, from tradition and the Brazilian Culture of oral story-telling. In order to get to know and draw a profile of this storyteller, we ve chosen to use the comprehensive interview method by French Sociologist Jean Claude Kaufmann. The originality in the method consists of the qualitative data put together in situ , concentrated on the storyteller s narratives/speeches recorded on tape, which will be the focal point of this study. Our analysis method is based on tireless sessions of listening to interviews out of which we gathered information related to the storyteller, his practice in telling the tales, and his repertoire

Práticas discursivas e relações afetivas na contemporaneidade: o caso dos verbos ficar e namorar no contexto do vestibular da UFRN

This work is inserted to Applied Linguistic studies, concerned to the understanding that language is a social practice, bringing a qualitative research, discussing essential aspects that involve the subject and his/her discursive practice: signification and valuation. Due to this, we have elected as subject study, the sense and values attributed to the verbs make out and date searched on the articles written in the Vestibular 2005 process promoted by the Universidade Federal do Rio Grande do Norte (UFRN), that had the following instruction: In a relationship, is it better make out , just date , or, both, make out and date ? This research is based on the Circle of Bakhtin s dialogic theory, as well as in the notions of instability in the affective relationships nowadays and in the individualization and multiplicity of contemporaneous subjectivity. Those papers are important to analyze the meaning and values that the verbs make out and date present, nowadays, as expressions of an affective relationship and how this situation can interfere in the positions of subjectivity in a formal instance as a vestibular. Those textual productions reflect those relationships, confronting temporary ones, whose discuss is marked, in general, by social voices that evaluate to make out negatively and to date positively

Augusto Matraga: um hérói além do bem e do mal - uma perpectiva trágico-ntológica

The present dissertation analyses the philosophy of Friedrich Nietzsche (1844-1900) and the short story written by João Guimarães Rosa (1908-1967), A hora e vez de Augusto Matraga (1946) seeking to point out the possibility of the philosophic application of some Nietzschean ideas to enlarge the aesthetic value of the short story. It has been especially aimed at applying the concept of the noble superior being described by Nietzsche, the ubermensch, to the hero s ontological nature, Augusto Matraga. Nietzsche s postulates of the will to power, the elements suggested of the trial between Dionysus and Apollo and the ascetic ideal, will be especially relevant to this work, which intends to establish until what point the hero can be conceived as a good ascetic person, in so far as his noble ontological nature trespass the Christian morality, bringing him closer to the man who, according to Nietzsche, is beyond good and evil. Some Heideggerian concepts will also be relevant in order to reinforce the idea that the judgment created about Matraga is just an appearance that does not contemplate his essential Being, contributing to veil his real tragic-ontological valour, what implies that the aesthetic power of the short has been under valued

Vaga-lume na treva: a poesia de João Lins Caldas

This thesis analyses the poetry of João Lins Caldas (1888-1967), in Brazilian literature context, aiming at describing and understanding the main features of his poetry. Thus, this research presents a corpus to be worked on: the poems in Poeira do céu e outros poemas (2009). Our study is characterized by a biographical, historiographical and critical tendency, by trying to organize the manuscripts of the author and biographical aspects while analyzing his poems. It is showed the relation between Brazilian poetry written by some authors, since the parnasianism and symbolism period until the twentieth century. On the one hand, our analysis is based on the ideas and criticism by Antonio Candido (2006; 2002; 1985), discussing the process of formation of Brazilian literature and the procedure to analyse poetry. It is also based on the concept of poetry and resistance, developed by Alfredo Bosi (2000; 2002), and the notion of Brazilian matter, identified by Roberto Schwarz (1987, 1997, 1999). On the other hand, this work focuses on melancholy under the theoretical ideas of authors such as Aristotle (1998), Walter Benjamin (1984), Jaime Ginzburg (1997) and Moacyr Scliar (2003). This focus on melancholy contributes to a better understanding of one of the main themes found in the poems analysed. By studying the poetry of João Lins Caldas, it was perceived the relevance of melancholy and resistance in his verses. This can be seen in his dissonant language, characterized by the broken syntax in his verses, as well as contradictory images and complex meanings in his poetry. This causes the effect of unfamiliarity on the reader. His poetry is the result of a style that finds its place in the best moment of modern Brazilian poetry and reveals its singularity through the inverted syntax with powerful themes such as love, death, pain, delusion, loss, memory, nature and God. All of them are aspects of Brazilian historicity. Finally, the work of João Lins Caldas is part of a multifaceted poetry

O sertanejo e o sevilhano nos poemas de João Cabral de Melo Neto: o lusco-fusco barroco

The aim of this research is, starting from a Baroque reading, unfold the understanding of the poems by João Cabral de Melo Neto in the axis Pernambuco-Spain. From this perspective, the reading of poet s Obra Completa allows the appearance of two persons, one from Seville and other from the Brazilian countryside, whom curiously pulsate and reveal themselves from their homelands, Brazilian northeastern dry lands and Seville, to a labyrinthy meeting establishing a close and exciting relationship of cities apart but which mark a contiguous dialogue between both cultures. The theorical effort of this investigation permeates, approaches and contrasts the directions of, among others, Severo Sarduy (1999), Gilles Deleuze (2012) and Eugenio D Ors (unknown). Not traveling an anthropological bias, this study observes the Spanish space and the Brazilian northeastern dry lands space, joining the regional to the universal and analyzes the baroque game in the (re) construction of the both men s cultures. These elements fuse, approach and move away, causing a game of allusions to Pernambuco and Spain that show itself through a similar cultural bias and different at the same time. From this apprehension it is possible to understand the synthesis of the Brazilian arid northeast-Seville men as a update of seventeenth century Baroque coming from indexes that are shown over the particular written by João Cabral de Melo Neto, in the Iberian Baroque scenario and in the American one s