João Eduardo Azevedo Ramos da Silva

Planejamento de turnos de trabalho: uma abordagem no setor sucroalcooleiro com uso de simulação discreta

O Brasil e o maior produtor de cana-de-acucar do mundo, sendo responsavel pela geracao de 3 milhoes de empregos em toda a sua cadeia de suprimentos. A alimentacao constante das moendas durante o periodo de safra depende do bom gerenciamento das operacoes de corte, carregamento e transporte de cana-de-acucar das fazendas para as usinas. A entrega de cana-de-acucar deve ser garantida para que o risco de parada da producao industrial de acucar e alcool seja evitado. Este trabalho foca o desenvolvimento e a utilizacao de um modelo de simulacao discreta para a determinhacao do sistema de turnos de trabalho dos operadores de equipamentos agricolas de uma usina no Estado de Sao Paulo, considerando os requisitos de moagem, o risco da falta de materia-prima e o limite permitido das jornadas de trabalho. Quatro cenarios foram propostos para avaliacao, sendo o primeiro com a troca de turnos unificada as 7 e as 19 horas; e os demais com a entrada em operacao de uma das frentes de corte e carregamento com 2, 4 e 6 horas de defasagem em relacao as demais frentes (escalonamento). O cenario com escalonamento de quatro horas de defasagem apresentou o melhor desempenho ao conciliar a entrega de cana, as jornadas de trabalho e o risco de desabastecimento. A discussao e focada no caso selecionado, mas estudos similares podem ser aplicados a outras usinas de acucar e alcool ou a outros processos do setor sucroalcooleiro.

BIOMASS SUPPLY CHAIN ANALYSIS WITH DENSIFIED WASTE

The possibility to vary the energy matrix, thus reducing the dependency on fossil fuels, has amplified the acceptance of biomass as an alternative fuel. Despite being a cheap and renewable option and the fact that Brazil is a major producer of waste from agriculture and forestry activities, the use of these materials has barriers due to its low density and low energetic efficiency, which can raise the costs of its utilization. Biomass densification has drawn attention due to its advantage in comparison to in natura biomass due to its better physical and combustion characteristics. The objective of this paper is to evaluate the impact of biomass densification in distribution and transport costs. To reach this objective, a mathematical model was used to represent decisions at a supply chain that coordinates the purchase and sale of forestry and wood waste. The model can evaluate the options to deliver biomass through the supply chain combining demand meeting and low cost. Results point to the possibility of an economy of 60% in transport cost and a reduction of 63% in the required quantity of trucks when densified waste is used. However, costs related to the densifying process lead to an increase of total supply costs of at least 37,8% in comparison to in natura waste. Summing up, the viability of biomass briquettes industry requires a cheaper densification process.

LOGÍSTICA REVERSA: ESTUDO DE CASO EM UMA EMPRESA DE REMANUFATURA DE EXTINTORES DE INCÊNDIO.

Concerns about the environment have led the society to develop new procedures to properly allocate the products that have reached the end of its useful life. From the point of view of companies operating channels of reverse logistics it is important to ensure both business viability and environmental compliance. This article presents a single case study and exploratory with the purpose of comparing motivations and difficulties for the operation of the reverse channel remanufacturing with the literature, in the case of fire extinguishers. For this reason, technical visits and interviews were conducted in a company that recharges fire extinguishers in Sorocaba region. The results showed that, in accordance with the literature, the extinguishers remanufacturing process provides economic and strategic advantage due to the opportunity to carry out other services such as installation of fire preventing and fighting systems, works maintenance, monitoring of Firefighters Survey and fire brigades training. On the other hand, the researched company does not present the typical problems reported in the literature about the uncertainties regarding the collection of extinguishers, their quality and acquisition of carcasses.Therefore concludes that the company has a well-established reverse logistics operation.