Work in Progress: Building Conceptual Understanding in the Mass and Energy Balances Course through Qualitative Analysis and Interactive Demonstrations

Sakul Ratanalert; Franklin Hsu; Nagma Zerin

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Conference: 2024 ASEE Annual Conference & Exposition
Location: Portland, Oregon
Publication Date: June 23, 2024
Start Date: June 23, 2024
End Date: June 26, 2024
Conference Session: WIP: Classroom Innovations
Tagged Division: Chemical Engineering Division (ChED)
Page Count: 6
DOI: 10.18260/1-2--48343
Permanent URL: https://peer.asee.org/48343
Download Count: 40

Paper Authors

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Sakul Ratanalert Columbia University orcid.org/0000-0002-1766-807X

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Sakul Ratanalert is a Senior Lecturer in Discipline in the Department of Chemical Engineering at Columbia University. He received his BS in Chemical and Biomolecular Engineering from Cornell University, and his MS in Chemical Engineering Practice and his PhD in Chemical Engineering from MIT. His current research interests include developing engaging learning activities and building students' intuition and conceptual understanding.

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Franklin Hsu The Johns Hopkins University

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Franklin Hsu graduated with honors in Chemical and Biomolecular Engineering from Johns Hopkins University in 2023. His academic pursuits have primarily centered on researching cancer metastasis and devising strategies to impede its advancement. Introduced to educational research by Dr. Sakul Ratanalert, he's inspired to remove barriers for underprivileged students in academia and medicine. He presently resides in Pennsylvania and is employed as an ophthalmic medical assistant.

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Nagma Zerin The Johns Hopkins University orcid.org/0000-0002-7876-8488

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Dr. Nagma Zerin is a Lecturer in the Chemical and Biomolecular Engineering (ChemBE) department at the Johns Hopkins University. She has a high interest in understanding the mindsets of undergraduate students and implementing inclusive classroom strategies.

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Abstract

Many students in chemical engineering are adept at solving systems of equations, but they struggle with understanding the meaning behind the variables and values, which leads to a lack of conceptual understanding and reduced critical thinking. This often hinders the students’ abilities to apply the concepts while solving practical problems. To address this issue, we restructured some problem statements in the Mass and Energy Balances course. To isolate conceptual understanding from mathematical ability, we dedicated questions on exams where the students were asked to qualitatively analyze relationships between different variables. We developed active-learning computational demonstrations that students could explore in a self-paced manner by manipulating variables and observing the effects on other variables, working in groups and guided by a teaching assistant (TA) and a problem set during recitation. One exam question asked students to predict the effects of changing one stream or system variable on another in a reactor process with recycle. To reinforce this, students worked with an interactive demonstration that displayed a block flow diagram of the process, using a mixer, reactor, separator, and splitter. Partial flow rates of each species were shown in a bar graph, and single-pass and overall fractional conversion, yield, and selectivity were shown in pie charts. Students could change inlet molar flow rate, single-pass fractional conversion, fractional selectivity, separator splits, and recycle ratio, individually manipulating one while holding the others constant. The flow rates and fractions adjusted automatically, obeying the material balance equations that the students were introduced to earlier. Another exam question asked students to predict the effects of changing parameters of a system of two flash drums connected in series at vapor-liquid equilibrium. To reinforce this, students worked with an interactive demonstration that displayed stream compositions and temperatures on a Txy vapor-liquid equilibrium diagram of a binary system, along with a diagram below with stream flow rates to illustrate the “lever rule” that arises from material balances. Students could adjust the inlet composition, temperature of each flash drum, and whether the second flash drum was connected to the vapor or liquid outlet of the first flash drum. The relative magnitudes of stream flow rates and their compositions adjusted automatically, and cases such as working outside of the vapor-liquid envelope were allowed, to demonstrate the effects of impractical design choices. This focus on conceptual understanding will not only build students’ intuition and critical thinking skills but also instill more confidence and engagement in the content beyond solving equations.

Citation
Format

Ratanalert, S., & Hsu, F., & Zerin, N. (2024, June), Work in Progress: Building Conceptual Understanding in the Mass and Energy Balances Course through Qualitative Analysis and Interactive Demonstrations Paper presented at 2024 ASEE Annual Conference & Exposition, Portland, Oregon. 10.18260/1-2--48343

TY  - CPAPER
AB  - Many students in chemical engineering are adept at solving systems of equations, but they struggle with understanding the meaning behind the variables and values, which leads to a lack of conceptual understanding and reduced critical thinking. This often hinders the students’ abilities to apply the concepts while solving practical problems. To address this issue, we restructured some problem statements in the Mass and Energy Balances course. To isolate conceptual understanding from mathematical ability, we dedicated questions on exams where the students were asked to qualitatively analyze relationships between different variables. We developed active-learning computational demonstrations that students could explore in a self-paced manner by manipulating variables and observing the effects on other variables, working in groups and guided by a teaching assistant (TA) and a problem set during recitation. 
One exam question asked students to predict the effects of changing one stream or system variable on another in a reactor process with recycle. To reinforce this, students worked with an interactive demonstration that displayed a block flow diagram of the process, using a mixer, reactor, separator, and splitter. Partial flow rates of each species were shown in a bar graph, and single-pass and overall fractional conversion, yield, and selectivity were shown in pie charts. Students could change inlet molar flow rate, single-pass fractional conversion, fractional selectivity, separator splits, and recycle ratio, individually manipulating one while holding the others constant. The flow rates and fractions adjusted automatically, obeying the material balance equations that the students were introduced to earlier.
Another exam question asked students to predict the effects of changing parameters of a system of two flash drums connected in series at vapor-liquid equilibrium. To reinforce this, students worked with an interactive demonstration that displayed stream compositions and temperatures on a Txy vapor-liquid equilibrium diagram of a binary system, along with a diagram below with stream flow rates to illustrate the “lever rule” that arises from material balances. Students could adjust the inlet composition, temperature of each flash drum, and whether the second flash drum was connected to the vapor or liquid outlet of the first flash drum. The relative magnitudes of stream flow rates and their compositions adjusted automatically, and cases such as working outside of the vapor-liquid envelope were allowed, to demonstrate the effects of impractical design choices.
This focus on conceptual understanding will not only build students’ intuition and critical thinking skills but also instill more confidence and engagement in the content beyond solving equations.
AU  - Sakul Ratanalert
AU  - Franklin Hsu
AU  - Nagma Zerin
CY  - Portland, Oregon
DA  - 2024/06/23
PB  - ASEE Conferences
TI  - Work in Progress: Building Conceptual Understanding in the Mass and Energy Balances Course through Qualitative Analysis and Interactive Demonstrations
UR  - https://peer.asee.org/48343
DO  - 10.18260/1-2--48343
ER  -