Caracterização do concentrado de ilmenita produzido na Mina do Guaju, Paraíba, visando identificar inclusões de monazita e outros contaminantes

O presente estudo tem como proposta, identificar o modo como o mineral monazita se encontra no concentrado final de ilmenita. Este concentrado é o produto resultante do beneficiamento do minério extraído de depósitos do tipo pláceres, conhecidos como depósitos de areias pretas. Estes depósitos são formados por dunas litorâneas pertencentes à jazida do Guaju, no município de Mataraca-PB. Todo o processo de lavra e beneficiamento deste minério ocorre na Mina do Guaju, a qual é operada pela empresa Millennium Inorganic Chemicals do Brasil S/A, pertencente a Lyondell Chemical Company. A ilmenita é um mineral composto por óxido de ferro e titânio, FeTiO3. Quase toda a ilmenita produzida na mina é transferida para o processo de fabricação de pigmento. A exigência para o uso na fabricação de pigmento é de que o concentrado final de ilmenita tenha um teor mínimo de 53% de TiO2 e um teor máximo de 0,1% de P2O5, entre outras substâncias. A monazita é o principal mineral fonte de óxido de tório, que é radioativo. No processo de fabricação de pigmento, a monazita é um contaminante indesejado. De acordo com a proposta de trabalho, foi feito um estudo de caracterização mineralógica de amostras do concentrado final de ilmenita fornecidas pela empresa. Inicialmente foram feitas análises em lupa, onde muitos grãos de leucoxeno foram identificados. O leucoxeno é uma alteração da ilmenita que permanece com as mesmas características magnéticas e eletrostáticas, tornando impossível, assim, a sua separação no processo de concentração. Também foi verificada a existência de grãos de monazita liberados em pequenas quantidades neste concentrado, indicando uma provável ineficiência no processo de separação. Numa segunda etapa foram realizadas análises dos grãos de ilmenita com o uso de um Microscópio Eletrônico de Varredura (MEV) acoplado a um Espectrômetro de Dispersão de Energia (EDS), para permitir a determinação de elementos químicos na amostra. Esta análise teve como objetivo verificar a existência de inclusões de monazita nos grãos de ilmenita. Porém, o que se observou foi a existência de algumas inclusões de quartzo e de alguns vazios deixados, provavelmente, por inclusões arrancadas durante o processo de preparação das amostras. Alguns destes vazios apresentaram formas semelhantes a de cristais de monazita, indicando a possibilidade da existência de inclusões deste mineral. Entretanto, a quantidade de grãos com possíveis inclusões de monazita é muito pequena, sendo insignificante como contaminante do concentrado final. Embora alguns vazios se assemelhem à forma da monazita, nenhum dos resultados do EDS identificou vestígios de sua presença. Ao final deste estudo ficou evidente que a principal fonte de contaminação do concentrado final de ilmenita corresponde à monazita, a qual se encontra liberada neste concentrado. Desta forma, há a necessidade de se melhorar o processo de separação dos minerais, de modo que a quantidade de monazita no concentrado final seja a menor possível, não prejudicando o rendimento da recuperação de ilmenita.

Coordenação no sistema agroindustrial da borracha natural : um estudo das relações entre produtores rurais e usinas beneficiadoras paulistas

O enfoque da Nova Economia Institucional é utilizado no estudo de sistemas agroindustriais brasileiros, mas ainda há poucos trabalhos sobre as relações entre produtores rurais e indústrias processadoras. O objetivo deste estudo é aferir o alinhamento das características das transações com os modos de governança adotados na comercialização de borracha natural entre produtores rurais e indústrias de beneficiamento primário. Busca-se confrontar os resultados com as previsões da teoria da Economia dos Custos de Transação, que prevê a adoção da governança mais eficiente, contingenciada ao ambiente transacional. Esta pesquisa utiliza um enfoque pioneiro para o setor. A primeira parte consiste na exploração qualitativa das transações entre produtores rurais e usinas beneficiadoras e na descrição dos elementos que compõe o sistema agroindustrial da borracha natural no Estado de São Paulo. Os resultados desta etapa são utilizados para refinar as hipóteses da etapa quantitativa, que relacionam os modos de governança adotados aos investimentos em ativos específicos, como o plantio de seringueiras, à frequência, à incerteza e à assistência técnica associadas à transação. Os resultados, apesar das limitações devido ao tamanho pequeno da amostra, sugerem que a quantidade de borracha comercializada influi positivamente na adoção de modos de governança mais coordenados e que a recorrência das transações provavelmente está associada a contratos relacionais. A hipótese da endogeneidade é rejeitada.

A7

Reciclagem e beneficiamento de produtos eletro-eletrônicos. Localização: Jaguariúna (SP)

Influência da adição de resíduo de caulim nas propriedades tecnológicas de uma massa padrão de porcelanato produzido em escala industrial

VARELA, M. L. et al. Influência da adição de resíduo de caulim nas propriedades tecnológicas de uma massa padrão de porcelanato produzido em escala industrial. Cerâmica, v.55, n.334 p.209-215. 2009.ISSN 0366-6913.Disponível em: ://www.scielo.br/scielo.php?pid=S0366-69132009000200015&script=sci_abstract&tlng=pt>. Acesso em: 06 out. 2010.

Tributos indiretos na cadeia produtiva do camarão

The state of Rio Grande do Norte counts with a relevant potential in the shrimp farming supply chain. In the larviculture step the state responds for more than half of the national production. In the farming step it is the second largest producer. In the industrial step, its industries have almost 40% of the shrimp processing capacity of the northeast of Brazil. However, this country has the highest tax rate comparing with the main shrimp producer countries. Considering the influence of taxes in the competition among companies, the main goal of this research is to analyze the impact of indirect taxes in the above steps of the supply chain. To achieve it, it will be used the data of the 2011 Census of the Shrimp Farming and it will be applied the Herfindahl-Hirschman Index to identify the market form of those steps. In order to contribute with the characterization of the supply chain, CEO´s of farms and industries will be interviewed. The price-elasticity of the shrimp larvae, the in natura shrimp and the processed shrimp will be analyzed in order to verify the possibility that each one of those three steps has to pass-through the onus of the end of benefit over the ICMS. The data analysis shows that the larviculture step functions as a duopoly and, facing the end of that benefit, it will be able to pass-through most its onus to the farming step. On the other hand, this step functions similar to a perfect competing market, which diminishes its capacity to pass-through that onus to the processing step. This step operates as oligopoly with a lower concentration than the larviculture step but, due to the fact that it faces an oligopsony, it will end up assuming most of that onus, which will cause a decrease in the amount of processed shrimp. It is concluded that the end of that benefit would impact negatively, in this state, the supply chain at all, but mainly the farming and the industrial steps

Adição de subprodutos da cinza da casca de café (coffea canephora) em massa cerâmica para porcelanato

To produce porcelain tiles fluxing agents are used in order to obtain a liquid phase during firing. This liquid phase fills the pores decreasing porosity, water absorption and contributes to material densification. In the porcelain tiles industry, feldspar is the main flux material used, with quantities ranging between 35 and 50%. Studies focus on the discovery of materials with flux characteristics that can reduce the consumption of feldspar by porcelain tiles industry. In this context, the coffee husk ashes, a residue obtained when coffee husks are burned to produce heat for the dryers during the processing of the green fruit, have as main chemical constituents potassium, calcium and magnesium, giving them characteristics of fluxing material. Brazil is the largest coffee producer in the world and is responsible for over 30% of the world s production. In this work a physical treatment of coffee husk ash was carried out in order to eliminate the organic matter and, after this, two by-products were obtained: residual wastes R1 and R2. Both residues were added separately as single fluxes and also in association with feldspar in mixtures with raw materials collected in a porcelain industry located in Dias d Ávila-Ba. The addition of these residues aimed to contribute to the reduction of the consumption of feldspar in the production of porcelain tiles. Specimens were produced with dimensions of 60 mm x 20 mm x 6 mm in an uniaxial die with compacting pressure of 45 MPa. The samples were heated to a temperature of 1200 °C, for 8 minutes. Tests were performed to characterize the raw materials by XRF, XRD, particle size analysis, DTA and TGA and, additionally, the results of the physical properties of water absorption, apparent porosity, linear shrinkage, density, dilatometry, flexural strength and SEM of sintered body were analyzed. Additions of less than 8% of the residue R1 contributed to the decrease of porosity, but the mechanical strength of the samples was not satisfactory. Additions of 5% the R2 residue contributed significantly to decrease the water absorption and apparent porosity, and also to increase the mechanical strength. Samples with addition of feldspar associated with the R2 residue, in proportions of 6.7% of R2 and 6.7% of feldspar, led to results of water absorption of 0.12% and mechanical strength of 46 MPa, having parameters normalized to the manufacture of porcelain stoneware tiles

Estudo de adsorvente obtido de terras diatomáceas para remoção de metais pesados em águas produzidas: processamento, caracterização e dinâmica em leito fixo

The acceleration of industrial growth in recent decades on all continents aroused the interest of the companies to counter the impacts produced on the environment, spurred primarily by major disasters in the petroleum industry. In this context, the water produced is responsible for the largest volume of effluent from the production and extraction of oil and natural gas. This effluent has in its composition some critical components such as inorganic salts, heavy metals (Fe, Cu, Zn, Pb, Cd, ), presence of oil and chemicals added in the various production processes. In response to impact, have been triggered by research alternative adsorbent materials for water treatment and water produced, in order to removing oils and acids and heavy metals. Many surveys of diatomaceous earth (diatomite) in Brazil involve studies on the physico-chemical, mineral deposits, extraction, processing and applications. The official estimated Jazi are around 2.5 million tonnes, the main located in the states of Bahia (44%) and Rio Grande do Norte (37,4%). Moreover, these two states appear as large offshore producers, earning a prominent role in research of adsorbents such as diatomite for treatment of water produced. Its main applications are as an agent of filtration, adsorption of oils and greases, industrial load and thermal insulator. The objective of this work was the processing and characterization of diatomite diatomaceous earth obtained from the municipality of Macaíba-RN (known locally as tabatinga) as a low cost regenerative adsorbent for removal of heavy metals in the application of water produced treatment. In this work we adopted a methodology for batch processing, practiced by small businesses located in producing regions of Brazil. The characterization was made by X-ray diffraction (XRD), scanning electron microscopy (SEM) and specific surface area (BET). Research conducted showed that the improvement process used was effective for small volume production of diatomite concentrated. The diatomite obtained was treated by calcination at temperature of 900 oC for 2 hours, with and without fluxing Na2CO3 (4%), according to optimal results in the literature. Column adsorption experiments were conducted to percolation of the in nature, calcined and calcined fluxing diatomites. Effluent was used as a saline solution containing ions of Cu, Zn, Na, Ca and Mg simulating the composition of produced waters in the state of Rio Grande do Norte, Brazil. The breakthrough curves for simultaneous removal of copper ions and zinc as a result, 84.3% for calcined diatomite and diatomite with 97.3 % for fluxing. The calcined fluxing diatomite was more efficient permeability through the bed and removal of copper and zinc ions. The fresh diatomite had trouble with the permeability through the bed under the conditions tested, compared with the other obtained diatomite. The results are presented as promising for application in the petroleum industry

Influência da adição de cinza do bagaço de cana calcinada em sistemas de pastas para cimentação de poços petrolíferos

Cementing operation is one of the most important stages in the oil well drilling processes and has main function to form hydraulic seal between the various permeable zones traversed by the well. However, several problems may occur with the cement sheath, either during primary cementing or during the well production period. Cements low resistance can cause fissures in the cement sheath and compromise the mechanical integrity of the annular, resulting in contamination of groundwater and producing zones. Several researches show that biomass ash, in particular, those generated by the sugarcane industry have pozzolanic activity and can be added in the composition of the cementing slurries in diverse applications, providing improvements in mechanical properties, revenue and cement durability. Due to the importance of a low cost additive that increases the mechanical properties in a well cementing operations, this study aimed to potentiate the use of sugarcane bagasse ash as pozzolanic material, evaluate the mechanisms of action of this one on cement pastes properties and apply this material in systems slurries aimed to cementing a well with 800 m depth and geothermal gradient of 1.7 °F/100 ft, as much primary cementing operations as squeeze. To do this, the ash beneficiation methods were realized through the processes of grinding, sifting and reburning (calcination) and then characterization by X-ray fluorescence, XRD, TG / DTG, specific surface area, particle size distribution by laser diffraction and mass specific. Moreover, the ash pozzolanic activity added to the cement at concentrations of 0%, 20% and 40% BWOC was evaluated by pozzolanic activity index with lime and with Portland cement. The evaluation of the pozzolanic activity by XRD, TG / DTG and compressive strength confirmed the ash reactivity and indicated that the addition of 20% in the composition of cement slurries produces improvement 34% in the mechanical properties of the slurry cured. Cement slurries properties evaluated by rheological measurements, fluid loss, free fluid, slurry sedimentation, thickening time and sonic strength (UCA) were satisfactory and showed the viability of using the sugarcane ash in cement slurries composition for well cementing

Qualidade microbiológica de leite UHT caprino: pesquisa de bactérias dos gêneros Staphylococcus, Bacillus e Clostridium

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Germinação de sementes de Caesalpinia leiostachya (benth.) ducke (pau-ferro) classificadas pelo tamanho e pela forma

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Produção e germinação de sementes de cultivares de aveia sob irrigação em Jaboticabal - SP

Em ensaios conduzidos nos anos de 2000 e 2001, avaliaram-se a produção de sementes, o peso de mil sementes e a germinação das sementes de cultivares de aveia. Os ensaios foram conduzidos em parcelas dispostas em blocos ao acaso com três repetições. No primeiro ano, as cultivares avaliadas foram: IAC-7, UFRGS-17, UFRGS-14, UPF-16 e OR-2, e no segundo ano: IAC-7, UFRGS-17, UPF-16, UFRGS-15 e UPF-19. As semeaduras ocorreram em 21/06/00 e 30/05/01. A colheita das sementes ocorreu no estádio de grãos duros, e, em seguida, realizou-se o beneficiamento. A cultivar IAC-7 foi a mais precoce em ambos os anos, e no segundo ano, observou-se aumento no ciclo de cultivo de todas as cultivares. Assim como o peso de mil sementes, a produção de sementes e o percentual de germinação das mesmas aumentaram no segundo ano. Embora não tenha havido diferenças entre as cultivares avaliadas no ano de 2001, no aspecto geral, a cultivar UFRGS-17 destacou-se das demais, apresentando alta produção e excelente germinação de sementes nos dois anos de avaliação. Foram encontrados altos valores para a porcentagem de germinação das sementes em ambos os anos, observado-se diferenças entre as cultivares apenas no primeiro ano.

Competitividade na pequena produção agroindustrial: estudo na agroindústria da castanha de caju

This paper looks into the cashew nut industrial process as a factor in adding value to it and involves its productions, industrialization and marketing. Its competitiveness fundamentally depends in its ability to surpass technological and non technological difficulties that contributes to increase costs and diminishes attributes to better qualities which means values to the market. The methodology applied in this paper was application of a questionnaire with a Likert model scale with closed questions and constituted by variables that composed nominated groups: exporting obstacles, market strategy, competitive advantages, broken nuts index, productive potential and social-economic profile of members of the Cooperative. A descriptive analysis was the method employed for the data analysis. After identifying some of the quantitative gains in the industrial process of the cashew nuts, recommendations are presented to COOPERCAJU to promote courses to improve the members productivity as well as technical assistance, in order to get more efficacy in the cashew nuts industrial processing

Analise SWOT do gerenciamento de resíduos do coco verde em duas agroindústrias do estado do Rio Grande do Norte

In the current conjuncture, the environmental factor has been changing the position of companies that are practicing or minimally adopting environmental management. Such tool has been used by companies to face the problems caused by solid waste, in particular green coconut waste, which is constantly among the material discarded by society (companies/ consumer). It is a typical tropical fruit whose fresh water is very benefic for human health, and its popularization has caused a progressive increase of its consumption. Following this stream of thought, this present work came up with an analysis of strengths, weaknesses, threats, and opportunities SWOT analysis on green coconut solid waste management at two agribusiness companies in the state of Rio Grande do Norte (RN), Brazil, aiming to know the challenges and the potentials of this kind of waste. According to the approach of the problem, this work fits a descriptive, exploratory, and qualitative research. The data collection was obtained by a questionnaire and a structured interview, in order to evaluate the strategic posture of agribusiness companies through SWOT analysis, which is an English acronym for Strengths, Weaknesses, Opportunities and Threats. The SWOT analysis is an effective tool to analyze the internal and external environment of an organization. This tool contributes to locate the company at the environment in question and when well applied it enables the detection of mistakes, the strengthening of correct procedures, the avoidance of threats, and the bet on opportunities. The studied agribusiness industries have very similar profiles, such as a long business life span, and a strategy that extends the useful life of the fruit, by using its waste for the manufacturing of new subproducts. In both, the daily quantity of waste resulted of this process reaches approximately 20 thousand units of the fruit in high season, being necessary a focus directed at use and/or treatment of these waste. Further to SWOT analysis, it was ascertained that the agribusiness company A works through a defensive marketing strategy and acts vulnerably, in other words, unable of acting before this market segment, for it has decided to stop using the waste due to a lack of equipment and technology. On the other hand, the agribusiness company B has incorporated an offensive marketing strategy because even not possessing equipments, technology, and appropriated internal installations, it still insists on use and benefits of green coconut waste in its agribusiness. Thus, it is considered that the potential of green coconut waste management for the production of several subproducts reduces the impacts produced by inappropriate placement and generates profits in a short, medium and long term. Such profits being tangible and intangible, as the interest for sustainability actions is not only a matter of obtaining return on capital, but it is an important question in order to move on into business, since it is not enough to have quality on products and process nowadays. It is necessary to establish socio-environmental practices aiming the image of the company as the prevailing role on consumers buying decision

Queda de pressão estática por meio de uma coluna de noz macadâmia

As unidades de beneficiamento de macadâmia adotam silos secadores distintos, para cada etapa de secagem, a fim de garantir a manutenção da qualidade do produto pela redução da umidade a níveis desejáveis. Diante da necessidade de quantificar a resistência apresentada pelas nozes, submetidas a diferentes fluxos de ar durante a secagem, bem como avaliar a possibilidade de utilização de modelos empíricos, que estimem o gradiente de pressão a partir da vazão de ar, conduziram-se vários testes em laboratório para obtenção de dados experimentais e ajuste de modelos. Frutos de macadâmia (M. integrifolia), com umidade de 0,11 b.s., após limpeza e classificação, foram colocados no interior de um protótipo constituído por uma coluna de chapa galvanizada (com tomadas para medição da pressão estática), plenum e ventilador, sendo submetidos a diferentes fluxos de ar. Os testes consistiram de três medidas por profundidade, para cada um dos três lotes de nozes, perfazendo um total de nove medidas de pressão estática por profundidade na coluna. Os resultados obtidos permitiram concluir que os fluxos de ar testados apresentaram efeito significativo sobre a queda de pressão estática na coluna de macadâmia, a qual aumentou linearmente com a profundidade. Os dados experimentais ajustaram-se muito bem aos modelos de Shedd e Hunter, sugerindo sua boa aplicabilidade para a macadâmia.

Aproveitamento de resíduo de caulim em cerâmica branca

The world market of Kaolin has been growing as new investments for better quality of materials have been applied. This market produces amounts of dross that are put in the environment in a wrong way, causing damages to it. Trying to reduce these damages, researches have been done in an attempt to use kaolin dross in ceramic. The disposal of kaolin dross in the environment by the industries of the states of Rio Grande do Norte and Paraiba have great impact in society. Usually this dross is disposed clandestinely in places like roads, river banks and lands of small cities. The present work shows the characteristics of the kaolin produced by the mining company in Junco do Seridó, Paraiba state, western Seridó, 300 km from Natal, in the border of both states. After that, researches were done to study its physical and the chemistry characteristics, trying to see if it can be used in white ceramic. The samples got were bolted in fabric of 325# . The technological characteristics tried to use it as a product in white ceramic. For that, it was made a haracterization of the subject matter through enlargement analyses, ATG and ATD, elaborating three formulations that were burned in four different temperatures, 1175, 1200, 1250 and 1300 degrees centigrade up to 30 minutes. After the burning, the subjects were submitted to water absorbing tests, linear retreating, apparent porosity, apparent specific mass, resistance to flexibility and MEV. For one of the mixtures it was obtained demanded properties for a semi porous material