Sistema de controle e instrumentação da simulação dinâmica dos processos de sorção e dessorção em ciclos de refrigeração por adsorção física

Abstract

This work describes the project and the construction of a refrigerator prototype for physical adsorption that uses the pair charcoal activate-methanol. The methanol circulates in a closed system and under vacuous. The prototype of the adsorptive refrigerator is constituted by three main parts: (1) reactor of stainless steel with activated charcoal; (2) condenser/evaporator in a single component; (3) piping of stainless steel and flexible hose. The regeneration method for the adsorbato is Thermal Swing Adsorption - TSA. A resistive heater was projected, that involves the reactor, and it accomplishes the desorption of the methanol. The evaporator is on the semi-analytical scale that is linked to a computer. It was projected, simulated, mounted and validated several electronic circuits used in the refrigerator. The experiment is supervised and controlled by a computational program. The virtual instrumentation was used to substitute most of the equipments used for measurement and control of the system. The measures of the temperature and of the pressure of the adsorptive bed are accomplished in real time. A semi-analytical scale is used to measure, in real time, the mass of alcohol during the thermodynamic. The used controller was PID (proportional/integral/derivative). The collection of the experimental data and their respective correlations make possible to determine the parameters of the equation of Dubinin-Astakhov, that it represents the pair's used adsortivo thermodynamic balance. The thermodynamic state, defined for the temperature and pressure of the adsortive bed, as well as the amount of methanol in each cycle, they are supervised in real time, for a program computacional idealized in the graphic atmosphere of programming denominated LabView.