Análise energética de sistemas de produção de etanol de mandica,cana-de-açúcar e milho

Pós-graduação em Agronomia (Energia na Agricultura) - FCA

Análise da aplicabilidade da ferramenta FTA no estudo de falhas de manutenção em uma indústria

The competitiveness in the industrial sector is increasingly fierce. In this context, the quality of maintenance is often neglected due to the sense of urgency that arises in these companies. Thus, it becomes increasingly necessary to use tools of Reliability Centered Maintenance to assist in managing maintenance effectively and efficiently, and directing resources .This study aims to evaluate the use of the fault tree to identify critical paths in the maintenance sector in an industry. The proposal is uses the tools of Reliability Centered Maintenance (MCC) for the collection, disposal and prioritizing causes problems in the transport industry. The study has its focus on the theoretical foundation of problem solving methods and techniques to identify the root causes, using the fault tree

Aplicação da modelagem matemática no estudo de funções: uma proposta de atividade para as Escolas de Tempo Integral (ETI)

Pós-graduação em Matemática em Rede Nacional - IBILCE

Análise energética de sistemas de produção de etanol de mandioca, cana-de-açúcar e milho

The objective of this work was the analysis of the energetic ethanol production systems using as source of carbohydrates, manioc, sugar cane and maize crops. The searches were carried from the field in the Paranapanema River Valley, state of Sao Paulo in the operations of cultivation and industrial processing of raw materials for analysis. The expenditure of energy concerning the agricultural part was made by the energy consumption of stage production of one hectare of sugar cane, cassava and corn, tillage and planting procedure, inputs, driving the crop, harvest, transport industry and energy draining. The expenditure of energy referring to the part was made by the industry energy consumption of stage processing of one tonne of sugar cane, cassava and corn, in the operations of disintegration / milling, hydrolysis / treatment of the broth, fermentation, distillation and maintenance of equipment. Under the system of agronomic production of raw materials, manioc presented an energy expenditure below that of sugar cane and maize (9,528.33 MJ ha-1; 14,370.90 MJ ha-1 and 15,633.83 MJ ha-1, respectively). For the ethanol produced, the operations of cultivation has consumed 1.54 MJ l-1 with manioc; MJ 1.99 l-1 with sugar cane, and 7.9 MJ l-1 with the corn. In the industrial processing of a ton of raw material, sugar cane presented an energy cost less than the cassava and maize (1,641.56 MJ t-1; 2,208.28 MJ t-1 and MJ 3,882.39 t-1, Respectively), however, showed a higher cost than when they related to ethanol produced (19.38 MJ l-1; 11.76 MJ l-1 and 11.76 MJ l-1, respectively). In the final energy balance for each megajoules of energy invested in sugar cane were required 1.09 MJ (9%), for each megajoules of energy invested in manioc were required 1.76 MJ (76%) and for each megajoules energy invested in maize were required 1.19 MJ (19%). Overall, it appears that the manioc consumes less energy than sugar cane and corn crops in the process of agribusiness obtaining ethanol.

Hydrogen embrittlement in an AISI 1045 steel component of the sugarcane industry

This paper will present a failure analysis of a chain component, manufactured with AISI 1045 steel and used for sugarcane transport. During the fabrication process, this component is submitted to induction hardening, just on one surface, before the galvanizing process. The occurrence of surface cracks, during storage, disables the usage of these components. Chemical and metallographic analyses, tensile, fracture toughness, and hardness tests, and fractography were conducted in order to determine the causes of failure. The steel chemical composition was in accordance with AISI 1045. The metallographic analyses and fractography did not exhibit the presence of zinc into the cracks; this is an indication that the cracks occurred after the galvanizing process. Tensile and fracture toughness test results are as expected. The crack surface and the fracture toughness specimen surfaces showed two different fracture micromechanisms: dimples and intergranular. The delayed fracture associated with the predominance of intergranular fracture micromechanism at the induction hardened layer and the high hardness level is a clear indication of the hydrogen embrittlement. (c) 2008 Elsevier Ltd. All rights reserved.