Thermodynamics of non-isothermal diffusion at the extraction from cheese whey by Lupin

Abstract

In many cases, extraction is accompanied by thermal phenomena. We have established the possibility of intensifying the process through the use of heated cheese whey. Lupine has a geometric shape (sphere, cylinder, plate) loaded into an extractor filled with cheese whey. Due to the temperature difference between the solid and the liquid, temperature gradients are observed. As the body warms up, the temperature gradient decreases and then disappears. For example, an organized step temperature mode. However, such a regime should be technologically and energetically justified. Thus, during extraction there is a periodic non-stationarity. The emergence of this period is noted in the main works. The expression for the increase in entropy per unit time is written. Given the changes in entropy, the Gibbs equation is written. The basics of equations are the second laws of thermodynamics. As a result, the results obtained as a result of thermodynamic driving forces were obtained. The equations of energy (heat) and mass transfer of substances are written. Thermodynamic forces contribute to the formation of heat flux and mass flow of substances. The consumption of a substance depends not only on the gradient (diffusion), but also on the temperature gradient (thermal diffusion). Air temperature is defined as a temperature gradient. The differential equations of heat and mass transfer of Lykov were rewritten taking into account the extraction process. The numerical values of the coefficients Dт and aс they relate to the assessment of the effect of superposition effects (thermal diffusion and diffusion thermal conductivity). The overlay effect can be neglected, since the relatively small gradients of temperatures and concentrations arising in the lupine. It is noted that the possibility of simplified differential equations is associated with small values of the Lykov criterion. Because of this, there should be little.