Dynamic Characterization of Residence Times in a Non-Ideal Plug Flow Reactor Using Pulsed Tracers and Monitoring in MATLAB

Abstract

Plug flow reactors (PFR) are widely used in the chemical industry and constitute a fundamental component in the training of engineers, as they allow the study of the hydrodynamic behavior of non-ideal systems under controlled conditions. This work presents the design, construction, and experimental characterization of a vertical laboratory-scale plug flow reactor, complemented by an application developed in MATLAB App Designer for real-time data acquisition and analysis through flow, conductivity, and temperature sensors. Using the pulse tracer method with NaCl solutions, the residence time distribution (RTD) was determined over a flow range from 1 to 15 L/min and concentrations from 0.05 to 0.25 M. The results confirm that, under the studied conditions, the mean residence time depends exclusively on the volumetric flow rate and is independent of the amount of tracer injected. In addition, a rational empirical model was obtained that accurately describes the inverse relationship between flow rate and residence time, enabling rapid estimations without the need for additional experiments. Beyond its technical contribution, this proposal constitutes an innovative pedagogical tool that integrates physical experimentation, low-cost automation, and computational processing, strengthening key competencies in chemical engineering students and promoting active, reproducible teaching aligned with current challenges in higher education. This study is aligned with the Sustainable Development Goals SDG 4 (Quality Education), SDG 9 (Industry, Innovation and Infrastructure), and SDG 12 (Responsible Consumption and Production).