Concentrador solar disco parabólico de foco fixo para pasteurização solar da água

Abstract

Water is an essential resource for life that must meet drinking parameters so that it does not pose risks to human health. Annually millions of people worldwide die from waterborne diseases, especially in underprivileged communities and in rural areas, where it is more difficult to access public supplies. Therefore, the adoption of sanitary barriers such as filtration and disinfection at the point of consumption are important to ensure water quality. A viable and sustainable method to disinfect water in remote communities, especially in the Brazilian semiarid region, is by solar pasteurization (SOPAS), which consists of a physical treatment capable of eradicating microbiological contamination indicators using the properties of solar radiation for heat the water to temperatures above 65 ° C. The SOPAS technique can be performed using different models of collectors or solar concentrators. Scheffler's fixed-point parabolic solar concentrator is a modular technology that can be constructed in different dimensions and has the differential of keeping the focal point stationary throughout its operation, even allowing the focus and the operator to be under a shadow. Therefore, the objective of this work was to construct a prototype fixed parabolic solar concentrator of 0.30m² and a receiver furnace to reduce thermal losses to evaluate its energy performance and test it for the solar water pasteurization process in batch system. The optical efficiency of the reflector panel was 0.73 and the average conversion efficiency of absorbed solar energy into useful thermal energy was approximately 0.955. Considering combinations of exposure time at certain temperatures estimated in the literature, it was found during the tests that the concentrator heated 5 liters of water at temperatures sufficient to occur the solar pasteurization, thus demonstrating potential for microbiological treatment in alternative solution systems individuals, especially in the semiarid region.