Paulo Romeu Moreira Machado

Desempenho de um motor de trator agrícola em bancada dinamométrica com biodiesel de óleo de frango e misturas binárias com óleo diesel

Brazil, the world third largest producer of biodiesel, and also the third largest producer of chicken, may increase the energy matrix, using oil derived from chicken, as an alternative to fossil fuels and reduce dependence on soybean oil for this purpose. The country can produce over 350 million liters of chicken oil per year. Considering the application of alternative fuels on diesel engines in agricultural machinery. The study aimed to evaluate the performance of a engine agricultural tractor with 53kW coupled by PTO in dynamometer bench operating with methyl biodiesel oil chicken and mix with diesel oil. Fuels B5 (reference), B20, B40, B60, B80 and B100 mixtures were used. The power, torque, torque reserve, fuel consumption, energy consumption and thermal efficiency of the engine were evaluated. The trial was conducted with a completely random design (CRD) in a factorial design with six treatment, which was held after the analysis of variance and adjusted means for the regression equations. Losses were observed in the generation of power and torque, increase in fuel consumption, reduction of energy consumption and improvement in engine thermal efficiency, according to the increasing proportion of biodiesel in the blend.

Desempenho de misturas pré-aquecidas de óleo de soja cru e diesel como combustível para motores agrícolas

O oleo de soja e um dos oleos vegetais que tem potencial de uso como combustivel para motores diesel, pois e renovavel, seguro e de facil utilizacao. Em temperatura ambiente, o oleo cru apresenta uma viscosidade cerca de dez vezes maior que a do oleo diesel. Para reduzir a viscosidade do oleo de soja a niveis aceitaveis, e necessaria uma temperatura de aquecimento em torno de aproximadamente 60°C ou mistura-lo com oleo diesel. O objetivo deste estudo foi avaliar o desempenho do oleo de soja cru e suas misturas com oleo diesel, pre-aquecidas antes da bomba injetora entre 57°C e 68°C, como combustivel para motores diesel. O desempenho das misturas combustiveis foi avaliado num motor monocilindrico de injecao indireta e comparado com o obtido pelo oleo diesel. Os ensaios de curta duracao foram conduzidos entre 1.800 e 2.800rpm, sob condicao de plena carga em dinamometro hidraulico. Ensaios realizados a 68°C apresentaram sempre os melhores valores para torque, potencia e consumo especifico de combustivel do que a 57°C. Uma mistura composta por 70% de oleo de soja e 30% de oleo diesel, aquecida a 68°C, apresentou os melhores resultados.

Comportamento de um motor de ignição por compressão trabalhando com óleo Diesel e gás natural

The foresight of a petroleum shortage and an ecological conscience is moving scientists to look for new sources of energy and to develop more efficient combustion processes and reduced emissions. Natural gas is a reduced emission fuel, whose consumption increases every year. The present work evaluates a dual fuel compression ignition engine. The major portion of the fuel burned is natural gas. The Diesel fuel acts as combustion starter, which ignites under the compression heat. Diesel fuel is used only as an ignition source. The partial substitution of Diesel fuel by natural gas increases the combustion efficiency and achieves significant emission reduction, because the combustion of natural gas produces less emission than the combustion of Diesel fuel. Initially, it was made a reference test using only Diesel fuel for comparison with following tests. There were made tests with varied proportions of Diesel fuel and natural gas, and with variable injection angles. There were made three repetitions for each test, including the reference test. The best performance was obtained with 22% of Diesel fuel and 13 L min-1 of natural gas, and with the engine original injection angle (21o). In this case, the average power was 14% above the standard engine and the cost of consumption was 46% lower than the reference test.

UMA ABORDAGEM DE RELACIONAMENTO NO ENSINO DE BIOLOGIA COM AS QUESTÕES AMBIENTAIS MEIO AMBIENTE E OS EFEITOS SOBRE O CORPO HUMANO

RESUMO A influencia cada vez maior da ciencia na vida das pessoas exige que elas estejam bem informados para acompanhar as descobertas cientificas, avaliar os seus aspectos sociais e participar de forma esclarecida de decisoes que dizem respeito a toda a coletividade. Neste sentido, hoje em dia nao ha nada mais importante para a humanidade do que compreender como a natureza funciona. O futuro das pessoas esta na dependencia de o Homo sapiens aprender a viver sem danificar a maquina da natureza, a ponto de ela nao poder mais sustentar a civilizacao. No entanto, para compreender a maquina da natureza as pessoas precisam entender nao apenas como ela opera hoje, mas como foi construida.

EDUCAÇÃO AMBIENTAL: UM OLHAR SOBRE COMUNIDADES QUILOMBOLAS NA REGIÃO CENTRAL DO RIO GRANDE DO SUL

In the late nineteenth century was signed by Princess Isabel on May 13, 1888 the law Aurea, freeingall slaves. Aiming to raise questions and envi-ronmental health experienced by the marooncommunities of the central region of Rio Grande do Sul, this study aimed to research and propose theimple-mentation of a program of care to the health needs identified through comments related toenvironmental education and health, for the maroon communities. The study describes the programof government-Federal ProNEA National Environmental Education Programme, ECCP-SharingEducation Programme of the Secretariat of Rio Grande do Sul and the project-pylon Black Presence inthe Field, developed by Universidade Federal de Santa Maria, RS, Brazil. Makes refer-ence inparticular the Community Quilombola Penna Ernesto Carneiro, located in the district of Palma, SantaMaria. Health Care for the population with emphasis on environmental education. To perform thisresearch used literature search and photographic documentation as well as research cam-po(observation). The latter had the character to compare with the theoretical rea-bility of quilomboErnesto Carneiro Penna.