Students are Up to the PepsiCo Engineering Challenge

Tuesday, December 10, 2019
Christina Gray and Rachel Shubella

Christina Gray (left) and Rachel Shubella were among three collegiate teams presenting their creative ideas at the PepsiCo and Society of Women Engineers’ 2019 Student Engineering Challenge finals in Anaheim, California.

Rachel Shubella and Christina Gray are the latest college students to pass the Pepsi Challenge.

However, the Rose-Hulman Institute of Technology chemical engineering students weren’t taste testing soft drinks, but rather helping PepsiCo’s Food for Good initiative make healthy food more physically and financially accessible for low-income families.

Specifically, they have proposed a way to improve the cleaning process of the company’s transport totes, which are used to deliver millions of beverage products annually across the country.

The students’ creative idea earned second-place honors in the PepsiCo and Society of Women Engineers’ 2019 Student Engineering Challenge. It had female collegiate student teams from across the United States solving a real-world problem that PepsiCo faces in the areas of eCommerce, zero waste and process optimization.

Using their chemical engineering interests, Shubella and Gray, along with colleague Mary DeGuzman from the University of Illinois, developed an idea to use a supercritical carbon dioxide-based cleaning system to replace PepsiCo’s current inefficient cleaning method, which had an inconsistent wipe down process that wastes water and chemicals.

Cleaning with carbon dioxide is like sand blasting or metal bead blasting. However, unlike traditional blasting, supercritical carbon dioxide has physical properties somewhere between a liquid and gas. Its solubility characteristics can be controlled by the manipulation of temperature and pressure to remove contaminants within the totes. At the end of the non-toxic cleaning process, the carbon dioxide returns to a gaseous state while the contaminant is removed. The improved process removes a variety of particles so that each tote is thoroughly clean and available for future deliveries.

This would improve upon the current cleaning process which involves spraying a liquid cleaner and having the substance wiped down by an employee using a towel. This process is only partially effective, can’t keep up with production demand, has adverse health effects, generates hazardous waste and is costly.

“As soon as we came across the lab-scale concept of supercritical carbon dioxide cleaning, we knew if scaled up correctly, the idea could have an application to plastic totes,” says Shubella, a senior from Salt Lake, Utah, who also is majoring in chemistry. “It was fulfilling to apply aspects of my chemical engineering degree to the project, and exciting to turn the theory into a product.”

Gray, a sophomore from Crete, Ill., who has a second academic major in biochemistry and molecular biology, adds, “I thought it would be a good experience to follow a unique design through all aspects of the process, while also seeing how the information we were learning in (chemical engineering) class could be directly used in industry.”

The student team’s project proposal was among three chosen from several contestants to make formal presentations before a panel of judges, including PepsiCo officials, at the 2019 SWE Annual Conference in Anaheim, California. The event was attended by more than 16,000 young female engineers, scientists and U.S. college students.

A team from the University of Texas earned first-place honors, while students from the University of Illinois placed third.

“It was amazing to meet the women that create PepsiCo's various products and have them seem so excited about something our team came up with. I am glad to have made an impact on a few people from such a large company,” states Gray, an officer in Rose-Hulman’s SWE student chapter.

Disney Imagineer Rachel Hutter was SWE WE 19’s keynote speaker, and inspired Gray to follow in her career initiative to make a difference in other’s lives through engineering.

“If it wasn't for women like Rachel Hutter, there would be so many more barriers and most women wouldn't even try so many amazing things. I am grateful to follow in the footsteps of many women just like her and I have begun to expand my ‘squad’ by adding many inspiring women that I met from WE19 on LinkedIn,” Gray says.

Shubella, who is currently reviewing career options as a senior, states, “I enjoyed having the opportunity to share our unique idea and motivate others with our design. Most importantly, I loved learning how to inspire the next generation of female engineers and scientists. At WE 19, I loved being able to hear the success stories of many empowering women. It was interesting to hear of their relatable struggles and failures that shaped them into the person they are today.”