Anaerobic bio-digestion of concentrate obtained in the process of ultra filtration of effluents from tilapia processing unit

The objective of the present study was to evaluate the efficiency of the process of biodigestion of the protein concentrate resulting from the ultrafiltration of the effluent from a slaughterhouse freezer of Nile tilapia. Bench digesters were used with excrements and water (control) in comparison with a mixture of cattle manure and effluent from the stages of filleting and bleeding of tilapias. The effluent obtained in the continuous process (bleeding + filleting) was the one with highest accumulated population from the 37th day, as well as greatest daily production. Gases composition did not differ between the protein concentrates, but the gas obtained with the use of the effluent from the filleting stage presented highest methane gas average (78.05%) in comparison with those obtained in the bleeding stage (69.95%) and in the continuous process (70.02%) or by the control method (68.59%).

CURRENT ASPECTS OF FUEL ETHANOL-PRODUCTION IN BRAZIL

Brazil has become a great producer of bioethanol using sugarcane as the basic raw material. Fed-batch process and continuous process are used. Biogas generation from vinasse, production of dry yeast, and autolyzed bagasse for animal feed are making the ethanol production less polluting and more profitable. Bagasse surplus has also been converted into electrical energy. Another alternative use for bioethanol is its conversion to petrochemical derivatives. Up to the present, however, this conversion has been carried out on only a small scale by the industry.

Estudo genômico e transcritômico de isolados selecionados de alto rendimento de dorna de fermentação alcoólica de Saccharomyces cerevisiae

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relação entre a concentração dos compostos fenólicos do mosto e a eficiência da fermentação alcoólica por subprodutos em processo contínuo

The objective of this work was to evaluate the relationship between phenolic compounds and alcoholic fermentation efficiency. The yield of sugarcanebyproducts (glycerol, acidity, and biomass) was determined in a continuous process at SaoManoel Sugarcane Mill, (Sao Paulo, Brazil) during the 2011/2012 harvest period. The Saccharomyces cerevisiae strain used as inoculum was the CAT-1. During the harvest, the endogenous yeast outcompeted the selected strain, hence eliminating it from the process. This research consists of a case of study on the ethanol production facility. FolinCiocauteau and methylene blue method was used to assess phenolic compounds. The efficiencyof the byproducts generated during the fermentation processwas calculated. Statistics analyses were carried out using Pearson correlation and its significance, by thet-test. We concluded that the phenolic compounds within the must could not be correlated to the byproducts’fermentation efficiency calculated during a continuous fermentation process.

Photosynthetic efficiency and rate of CO2 assimilation by Arthrospira (Spirulina) platensis continuously cultivated in a tubular photobioreactor

Similar to other photosynthetic microorganisms, the cyanobacterium Arthrospira platensis can be used to produce pigments, single cell proteins, fatty acids (which can be used for bioenergy), food and feed supplements, and biofixation of CO2. Cultivation in a specifically designed tubular photobioreactor is suitable for photosynthetic biomass production, because the cultivation area can be reduced by distributing the microbial cells vertically, thus avoiding loss of ammonia and CO2. The aim of this study was to investigate the influence of light intensity and dilution rate on the photosynthetic efficiency and CO2 assimilation efficiency of A. platensis cultured in a tubular photobioreactor in a continuous process. Urea was used as a nitrogen source and CO2 as carbon source and for pH control. Steady-state conditions were achieved in most of the runs, indicating that continuous cultivation of this cyanobacterium in a tubular photobioreactor could be an interesting alternative for the large-scale fixation of CO2 to mitigate the greenhouse effect while producing high protein content biomass.

Development of a Mechanism and Process to Continuously Produce Spherical, Torrefied Biomass

Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2016-06-17 02:15:25.215

DEVELOPMENT OF A MECHANISM AND PROCESS TO CONTINUOUSLY PRODUCE SPHERICAL, TORREFIED BIOMASS PELLETS

A recently developed novel biomass fuel pellet, the Q’ Pellet, offers significant improvements over conventional white pellets, with characteristics comparable to those of coal. The Q’ Pellet was initially created at bench scale using a proprietary die and punch design, in which the biomass was torrefied in-situ¬ and then compressed. To bring the benefits of the Q’ Pellet to a commercial level, it must be capable of being produced in a continuous process at a competitive cost. A prototype machine was previously constructed in a first effort to assess continuous processing of the Q’ Pellet. The prototype torrefied biomass in a separate, ex-situ reactor and transported it into a rotary compression stage. Upon evaluation, parts of the prototype were found to be unsuccessful and required a redesign of the material transport method as well as the compression mechanism. A process was developed in which material was torrefied ex-situ and extruded in a pre-compression stage. The extruded biomass overcame multiple handling issues that had been experienced with un-densified biomass, facilitating efficient material transport. Biomass was extruded directly into a novel re-designed pelletizing die, which incorporated a removable cap, ejection pin and a die spring to accommodate a repeatable continuous process. Although after several uses the die required manual intervention due to minor design and manufacturing quality limitations, the system clearly demonstrated the capability of producing the Q’ Pellet in a continuous process. Q’ Pellets produced by the pre-compression method and pelletized in the re-designed die had an average dry basis gross calorific value of 22.04 MJ/kg, pellet durability index of 99.86% and dried to 6.2% of its initial mass following 24 hours submerged in water. This compares well with literature results of 21.29 MJ/kg, 100% pellet durability index and <5% mass increase in a water submersion test. These results indicate that the methods developed herein are capable of producing Q’ Pellets in a continuous process with fuel properties competitive with coal.

Anaerobic bio-digestion of concentrate obtained in the process of ultra filtration of effluents from tilapia processing unit

The objective of the present study was to evaluate the efficiency of the process of biodigestion of the protein concentrate resulting from the ultrafiltration of the effluent from a slaughterhouse freezer of Nile tilapia. Bench digesters were used with excrements and water (control) in comparison with a mixture of cattle manure and effluent from the stages of filleting and bleeding of tilapias. The effluent obtained in the continuous process (bleeding + filleting) was the one with highest accumulated population from the 37th day, as well as greatest daily production. Gases composition did not differ between the protein concentrates, but the gas obtained with the use of the effluent from the filleting stage presented highest methane gas average (78.05%) in comparison with those obtained in the bleeding stage (69.95%) and in the continuous process (70.02%) or by the control method (68.59%).

Recovery of gold(0) nanoparticles from aqueous solutions using effluents from a bioremediation process

The use of biological processes with the aim of the recovery of gold from low-concentration solutions derived from leaching of secondary sources is gaining increasing importance owing to the scarcity of the primary resources and the economic and environmental advantages usually presented by these methods. Thus, the addition in batch and continuous processes of different solutions containing biogenic sulphide, which was generated by the activity of sulphate-reducing bacteria (SRB), to gold(III) solutions was investigated for that purpose. In the batch experiments, AuS nanoparticles with sizes of between 6 and 14 nm were obtained (corresponding to 100% removal of Au(III) from solution) if the biogenic sulphide was generated in a typical nutrient medium for SRB, whereas Au(0) nanoparticles with sizes of below 8 nm were obtained (corresponding to 62% removal of Au(III)) if effluent from a SRB bioremediation process for treating acid mine drainage (AMD) was used instead. These results stimulated the development of a continuous process of addition, in which two sulphide-rich effluents, which resulted from a SRB bioremediation process for treating two types of AMD (from a uranium mine and a polysulphide mine), were tested. In both cases, Au(0) nanoparticles with sizes of between 6 and 15 nm were mainly obtained, and the percentage removal of Au(III) from solution ranged from 76% to 100%. The processes described allow the simultaneous treatment of AMD and recovery of metallic gold nanoparticles, which are a product with a wide range of applications (e.g., in medicine, optical devices and catalysis) and high economic value. The synthesis process described in this work can be considered as novel, because it is the first time, to our knowledge, that the use of effluent from a SRB bioremediation process has been reported for the recovery of gold(III) as gold(0) nanoparticles.

Novel Isolates for Biological Detoxification of Lignocellulosic Hydrolysate

In this paper, two new strians, Issatchenkia occidentalis (Lj-3, CCTCC M 2006097) and Issatchenkia orienalis (S-7, CCTCC M 2006098), isolated from different environments on solid media, were used in the detoxification process of the hemicellulosic hydrolysate of sugarcane bagasse. High-pressure liquid chromatography elution curve of UV-absorption compounds represented by acetic acid, furfural, and guaiacol (toxic compounds found in the hemicellulosic hydrolysate) showed that several chromatographic peaks were evidently diminished for the case of detoxified hydrolysate with isolate strains compared to the high peaks resulted for no detoxified hydrolysate. It was clear that these inhibitors were degraded by the two new isolates during their cultivation process. Fermentation results for the biodetoxified hydrolysate showed an increase in xylitol productivity (Q (p)) by 1.97 and 1.95 times (2.03 and 2.01 g l(-1) h(-1)) and in xylitol yield (Y (p)) by 1.72 and 1.65 times (0.93 and 0.89 g xylitol per gram xylose) for hydrolysate treated with S-7 and Lj-3, respectively, in comparison with no detoxified hydrolysate (1.03 g l(-1) h(-1) and 0.54 g xylitol per gram xylose). This present work demonstrated the importance of Issatchenkia yeast in providing an effective biological detoxification approach to remove inhibitors and improve hydrolysate fermentability, leading to a high xylitol productivity and yield.

A categoria dos auditores fiscais da Receita Federal do Brasil : a (des) construção da identidade profissional

Este artigo busca revelar o processo de desenvolvimento da categoria dos auditores fiscais da Receita Federal do Brasil (AFRFBs), a partir das mudanças no contexto social e profissional, e a forma como essas mutações concorreram para a construção de uma identidade profissional própria desses servidores. O que se pretende é entender como o contexto político-econômico vem alterando as percepções que esses profissionais têm de si próprios e como as reformas transformaram o modo de exercerem suas funções. A pesquisa, que se dá a partir de uma proposta de transação "quanti-quali", permitiu explorar, na trilha teórica de Dubar, aspectos relevantes do contínuo processo de construção das identidades profissionais ou de perfis identitários desses servidores. Os conhecimentos sobre o trabalho e as formas de identificação profissional na categoria dos auditores fiscais da Receita Federal do Brasil podem contribuir para a reflexão sobre relações de trabalho e processos de gestão pública no Brasil.

Construção e desenvolvimento da identidade profissional do educador de infância - percursos no masculino : um estudo de três casos

Dissertação de Mestrado em Supervisão em Educação, enquadrada na linha de investigação sobre Desenvolvimento Profissional dos Professores, apresentada à Escola Superior de Educação de Lisboa

O crédito concedido às empresas: antes e no decorrer da crise mundial. Análise e gestão do risco de crédito

O tema do trabalho de investigação é a análise do risco de crédito às empresas antes e durante a actual crise financeira, bem como a sua gestão. A gestão de risco de crédito das instituições financeiras tem-se transformado cada vez mais numa peça chave para toda a actividade bancária, tendo ainda mais significado no mundo actual, em constante mudança e globalização. A concessão de crédito às empresas tornou-se numa tarefa cada vez mais árdua, para as instituições financeiras devido ao risco de crédito. A presente dissertação foi desenvolvida visando os objectivos de efectuar uma avaliação na concessão de crédito a empresas durante a crise, com ênfase na gestão do risco de crédito, bem como na utilização do Acordo de Basileia II. Para atingir os objectivos traçados a metodologia utilizada foi o inquérito por questionário a colaboradores da Caixa Geral de Depósitos (CGD). O questionário foi efectuado, de forma a captar quer os desenvolvimentos passados, como recentes, bem como a evolução esperada. Relativamente à evolução passada, as perguntas respeitam aos anos anteriores à crise, enquanto as perguntas prospectivas se referem aos anos seguintes. O trabalho desenvolvido permitiu-nos concluir que as instituições financeiras mundiais, desde o início da recessão, têm restringido ao máximo a concessão de crédito às empresas. Muitas instituições têm-no feito através da exigência de mais garantias, aumento do spread, bem como a diminuição de maturidades. Todas estas situações geram um ciclo vicioso, na medida em que as empresas que se vêem confrontadas na restrição do acesso ao crédito, não têm condições para sobreviver, gerando assim várias falências.

Estudo do processo de fabricação de perfis híbridos pultrudidos

A realização deste trabalho teve como principal objectivo proceder ao projecto e realização de dois sistemas de produção de perfis pultrudidos híbridos a acoplar aos equipamentos de pultrusão já instalados na ALTO – PERFIS PULTRUDIDOS, Lda. A realização de perfis pultrudidos híbridos visa melhorar as características de isolamento térmico e acústico dos tubos habitualmente feitos por pultrusão, incrementando simultaneamente a sua resistência, através da melhoria do momento de inércia do perfil, sem que haja um aumento significativo do peso do conjunto. O projecto teve como base de trabalho dois sistemas de produção completamente distintos: (a) a existência de barras de cortiça e de poliuretano (pré-formas) sobre as quais se vai efectuar a pultrusão de um tubo que abraça as barras e (b) o uso de resíduos de pultrusão como forma de enchimento dos tubos, durante o seu processo produtivo. Estes equipamentos foram projectados e parcialmente fabricados, antevendo-se que os mesmos entrem em funcionamento muito brevemente.

Conceção e implementação de um programa de melhoria da qualidade: estudo de caso na Eurico Ferreira, S.A.

Os programas de melhoria contínua dos processos são cada vez mais a aposta das empresas para fazer face ao mercado. Através da implementação destes programas é possível conferir simplicidade e padronização aos processos e consequentemente reduzir os custos com desperdícios internos relacionados com a qualidade dos mesmos. As ferramentas de melhoria da qualidade e as ferramentas associadas ao Lean Thinking representam um pilar importante no sucesso de qualquer programa de melhoria contínua dos processos. Estas ferramentas constituem meios úteis na análise, controlo, organização de dados importantes para a correta tomada de decisão nas organizações. O presente projeto tem como principal objetivo a conceção e implementação de um programa de melhoria da qualidade na Eurico Ferreira, S.A., tendo por base a avaliação da satisfação do cliente e a aplicação dos 5S. Neste contexto, o trabalho teve como fundamentação teórica a Gestão da Qualidade, Lean Thinking e algumas ferramentas de ambas as matérias. Posteriormente foi selecionada a área de negócio da empresa a abordar. Após a seleção, realizou-se um diagnóstico inicial do processo identificando os diversos pontos de melhoria onde foram aplicadas algumas ferramentas do Lean Thinking, nomeadamente o Value Stream Mapping e a metodologia 5S. Com a primeira foi possível construir um mapa do estado atual do processo, no qual estavam representados todos os intervenientes assim como o fluxo de materiais e de informação ao longo do processo. A metodologia 5S permitiu atuar sobre os desperdícios, identificando e implementando diversas melhorias no processo. Concluiu-se que a implementação das ferramentas contribuiu eficientemente para a melhoria contínua da qualidade nos processos, tendo sido decisão da coordenação alargar o âmbito do projeto aos restantes armazéns do centro logístico da empresa. Pode afirmar-se com recurso à satisfação do cliente expressa através da evolução favorável do Service-level agreement que as ferramentas implementadas têm gerado resultados muito positivos no curto prazo.