Chemical Engineering Science, Vol.59, No.19, 4137-4147, 2004
Study of gas-liquid stirred reactor stability taking into account the temperature influence on gas solubility
The paper is devoted to the dynamic behavior and stability of gas-liquid stirred reactor taking into account the temperature influence on gas solubility. Since the rate of gas-liquid processes is very sensitive to concentration of gas reactant dissolved in liquid, even weak fluctuations of temperature can significantly influence on process pass. There are two cases of temperature influence on gas solubility are possible: (1) the solubility decreases with increasing temperature; (2) the solubility grows with increasing temperature. The first case is typical for majority of gases. The second case occurs more rarely but has a great practical importance. It takes place, for example, for the hydrogenation of many compounds in organic solvents (such as benzene, toluene, isopropyl alcohol and others). A model of gas-liquid process has been developed to demonstrate the stability of gas-liquid reactor. It has been shown that the gas solubility behavior has an influence on the form of heat production curve and therefore on the multiplicity of the steady states. The areas of multiplicity and limit cycles were found and the phenomenon of hysteresis in the reactor was shown. A criterion to determine whether the multiplicity is possible under the given conditions was found. By means of an analysis of a mathematical model the stability of steady states of the reactor was studied. (C) 2004 Elsevier Ltd. All rights reserved.
Keywords:multiphase reactors;dynamic simulation;stability;mathematical modeling;multiplicity;absorption