ZACARIAS, J. R. A.; http://lattes.cnpq.br/3512928585523190; ZACARIAS, João Rubens Alves.
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.
