Avaliação do uso de coletores solares para melhoria de um sistema de aquecimento de água em uma indústria de silicones de performance

Abstract

Energy, air and water are primordial factors in human life and in the beginning of primitive society they had practically no costs and limitations, as they were easily accessible and used, especially in domestic activities. In the other side, because of the evolutions leveraged by the expansion of industrialization in the late eighteenth century, the world had its energy demand increased. As a result of this increased use of natural resources, there was an intensification of the types of damage to the environment. To reduce current patterns of electricity production and consumption based on fossil sources, it is necessary to encourage the use and development of technologies that include renewable energy. Solar collectors, examples of photovoltaic energy source, were studied in this Undergraduate Work as an alternative for improving a process water heating system in a performance silicone industry. This Undergraduate Work described the current problems of the water heating system utilized, which possess electrical resistances. In addition, it performed the thermal modeling of this system through the differential energy balance. From the differential balance, executed the sensitivity analysis of the system, varying parameters such as the volume of water in the heating tank and its electrical power. Finally, it studied the application of solar collectors as an alternative to increase the electrical power, including the preliminary exergy and economic analysis. The results obtained indicate that the current heating system has a long time for heating a load of 10000 kg up to 75°C, which is 10 hours. In addition, increasing the volume of the heating tank did not improved the heating time of the fluid in the reactor. However, doubling the system power to 108 kW presented a significant gain in heating time, with a 60% decrease. The use of solar collectors as an alternative to increase power proved to be positive, having a project payback time of 6 years and 9 months, annual profit of R$ 9956 and a higher exergy efficiency (19,2%) when compared to the resistances system exergy efficiency (17,9%).