Dynamic simulation of a plate pasteurizer unit: Mathematical modeling and experimental validation

• Published in: Journal of food engineering 2014-06, Vol.131, p.124-134
• Main Authors: Gutierrez, Carola G.C.C., Diniz, Gabriel N., Gut, Jorge A.W.
• Format: Article
• Language: English
• Subjects: Computational fluid dynamics; Computer simulation; Dynamic simulation; Dynamics; Fluid flow; Fluids; Foods; Heat transfer; Heating; Mathematical modeling; Mathematical models; Pasteurization; Plate heat exchanger
• ISSN: 0260-8774; 1873-5770
• DOI: 10.1016/j.jfoodeng.2014.01.029

•Physical model is derived to simulate the dynamic operation of a plate pasteurizer.•Model is tested and validated using laboratory-scale equipment.•Process start-up and response to step changes in flow rates were investigated.•Predicted temperature profiles in good agreement with experimental data.•Virtual unit can be useful to test operational policies and process controllers. Continuous pasteurization is a thermal processing of fluid foods that targets the inactivation of microorganisms and enzymes that compromise food safety and product shelf life. A physical model based on conservation and transport equations is derived for the simulation of the dynamic operation of a plate pasteurizer unit that comprises three plate heat exchangers (heating, cooling and heat regeneration) and a non-isothermal holding tube. The mathematical model consists of a system of differential equations with boundary and initial conditions, which is solved numerically using a finite difference method. In order to test and validate the model, it was applied to the study of the dynamic behavior of a laboratory scale unit for the start-up operation and for disturbances on the process flow rates (product, heating fluid and cooling fluid). Temperatures were experimentally acquired in twelve positions along the processing unit. Through the comparison of experimental and simulated results, the model predictions were verified to be in good agreement with experimental data under various operating conditions. The model developed provides a virtual unit that is useful to test operational policies and process controllers.