(551a) Problem-Based Learning As a Venue to Educate Chemical Engineers about Fire and Explosion Safety

Chemical engineers play a very important role in fire and explosion safety, not only given their responsibility in process safety but also because they can fully understand the science behind the phenomena that take place in a fire or explosion. Even before the prevalence of physical modeling tools that characterizes the current practice of engineers, performance-based design has been identified as an important alternative to the more traditional prescriptive design used in industrial fire protection, particularly given the complexity and constantly changing character of modern industrial facilities (Zalosh, 2003). Unfortunately, exposure to concepts such as prescriptive- and performance-based design as well as to the state-of-the-art physical modeling tools available for the simulation of fires and explosions in the chemical engineering undergraduate curriculum is scarce.
While the theory behind fires and explosions is complex and experiments in this area are normally outside the scope of university laboratories, software that can simulate fires and explosions have become day-to-day tools to the fire safety practitioner. At the same time the combination of real-life cases and virtual practices has proven an effective way to introduce chemical engineers to complex chemical systems(Ramírez et al., 2020). This presentation describes how Problem-Based Learning (PBL) can be used to educate undergraduate chemical engineering students on fire and explosion safety. It particularly shows a real-life incident where an explosion in a tank-storage facility caused a pool fire.
The problem was presented to first-year students in the Introduction to Chemical Engineering class as well to last-year students in the Process Engineering course.
After a comprehensive description of the scenario that lists the chemicals present, a plant layout, and pictures and videos of the incident, students were first asked to explain why the tank exploded. For first-year students, this served to introduce concepts from basic physical chemistry such as vapor/liquid equilibrium and vapor pressure. Both first- and last-year students learn about basic process safety concepts such as flammability limits and consequence and risk analyses. A second question asked students to decide the best way to combine prescriptive and performance-based approaches to improve the design in order to minimize the consequences.
The Fire Dynamic Simulator(McGrattan et al., 2021), the most used software for fire analysis, was used to model the fire. While the use of the software was just demonstrated for first-year students, last-year students had an assignment that asked them to install the software and to simulate, based on a simple guide, the fire by themselves. The fire simulations addressed the effect of wind on the radiant heat flux to the tank walls that helped the students assess how differences in environmental conditions would favor a combination of descriptive- and performance-based design.
The case was implemented to 52 students of the Introduction to Chemical Engineering class and 16 students of the Process Engineering class. A survey was conducted before and after the students were exposed to the problems following a Likert 5-point scale. The survey assessed how important the students considered the ABET competencies (Problem solving through math, science & engineering, Engineering design, Experiments and data analysis, Lifelong learning, and Communication, Ethics, impact of engineering and contemporary issues) in fire and explosion safety. In both groups of students, the importance given to the competencies increased after exposure to the problem. This trend was particularly evident for the students in the Introduction to Chemical Engineering class. While the survey did not address how the problem contributed to the students understanding of basic physical chemistry and fire safety concepts, as it focused on the students perception of competencies, it became evident after the classes that the interest in these areas increased as students found a practical use to these concepts. In general the combination of PBL, application of physical modeling tools and real-life cases was found to be a strong venue to expose chemical engineering students to fire and explosion safety concepts.

Acknowledgments

This research was partially funded by the Royal Academy of Engineering under its Transforming Systems through Partnership 20/21 award with reference TSP2021/100311 (HERMES No. 51980): Training for the prevention of fires and explosions through the use of data analysis and simulation and by ICETEX and Ministerio de Ciencia, Tecnología e Innovación - Colombia through Contrato de Financiamiento de Recuperación Contingente No. 2022-0742. Vallejo-Molina recognizes the scholarship received from the Juan Pablo Gutierrez Cáceres foundation.

References
McGrattan, K., Hostikka, S., Floyd, J., McDermott, R., & Vanella, M. (2021, May). FDS-SMV. FDS-SMV Fire Dynamics Simulator (FDS) and Smokeview (SMV). https://pages.nist.gov/fds-smv/
Ramírez, J., Soto, D., López, S., Akroyd, J., Nurkowski, D., Botero, M. L., Bianco, N., Brownbridge, G., Kraft, M., & Molina, A. (2020). A virtual laboratory to support chemical reaction engineering courses using real-life problems and industrial software. Education for Chemical Engineers, 33, 36–44.
Zalosh, R. G. (2003). Industrial Fire Protection Engineering. Wiley.