Análise do tratamento térmico do argilomineral vermiculita utilizando energia de micro-ondas.

Abstract

This dissertation work presents the results of the study of heating and ex- clay mineral vermiculite using microwave energy. Vermiculite is a clay mineral used in several areas and presents commercial value after a process of thermal expansion. The thermal processes for expansion of vermiculite use sources not renewable sources that generate greenhouse gases. The use of microwave energy is a viable alternative to improve the efficiency of the vermiculite expansion process and mitigate the generation of greenhouse gases. In this work, the heating process of the vermiculite occurred in a short-circuited transmission line (metallic waveguide), where the vermiculite sample was exposed to a high energy microwave. From of thermographic measurements was analyzed and compared the heating process using of different powers, in a range of 50 W to 500 W. The tests were carried out with continuous and alternating power, in order to improve the efficiency of the heating process. cement. To analyze the efficiency of each test, the final volume of vermiculite was observed. expanded, processing time and energy spent on heating. The tests with switched companies showed a reduction in processing time and a 32% reduction in energy used in connection with continuous power testing. The permissiveness of vermiculite gross and expanded was measured in the tests, in order to analyze the variation of the dielectric characteristics. A microstrip planar resonant ring was constructed to characterize vermiculite before and after processing.