Every new year, I like to look back and reflect on my accomplishments in the past year. In 2022, my biggest accomplishment was graduating with a degree in chemical engineering from the Univ. of California, Los Angeles (UCLA). Although I took many difficult courses throughout my academic career, the most impactful yet rigorous experience was the senior design project, which took place the final two quarters of my senior year. This article details my experiences completing the senior design project.
The group and topic
Our senior design project was split across two courses. Our graduating class of approximately 70 students was divided into five groups, each tasked with designing a production plant. We were asked to select the site location, model the process, complete an economic analysis, and perform a hazard and operability (HAZOP) study, among other things. Each group had a student designated as the project manager, with the rest of the members split into groups of three, responsible for a unit operation of the plant.
My group was assigned an ammonia production plant, and my subgroup was tasked with sequestering the carbon from the ammonia recovery subgroup’s output stream, which contained CO2 and water. We designed a carbon dioxide compression system, sized a pipeline for transportation, and determined that for the sequestration method, the CO2 should be used for enhanced oil recovery (EOR). At UCLA, it was the first time students were tasked with designing such a system; this part of the project was added to fulfill new accreditation requirements to promote sustainability.
The project began with determining the needs of each section of the plant. Our project manager advised each subgroup to look into our section’s needs and pick three states in the U.S. that would accommodate them. From there, we would then go over each selection and try to find an overlap or compromise with what works best for the majority of the group. Eventually, our group settled on Texas, specifically along the Gulf of Mexico, as this location covered most of our feed gas needs. Our decision to pick that location was also impacted by other factors such as local legislation and labor costs. In addition, we investigated examples of ammonia production facilities that were currently operating. At the end of the first course, we shared the analysis of our site selection with our peers and professor through a 60-minute PowerPoint presentation.
Simulating the process
The second course began with drawing our process flow diagrams (PFDs) in Visio and running process simulations using PRO/II. This was the most difficult part of the entire project, as each subgroup modeled their unit operation on separate flowsheets and reported stream data to one another. If one subgroup had an error in their simulation or flowsheet, then it would affect all other systems downstream. At this point, we would often communicate with other subgroups to check in on their progress, while visiting our professor’s office hours to get input on our simulations.
Because carbon sequestration was a new addition to the project, my subgroup had no prior examples to learn from and we couldn’t find much helpful information online, so we conferred with our professor more heavily than other subgroups. One technical issue that we encountered was that the incoming stream to our system had a high water content, which is not ideal for EOR or for the pipeline, and could not be removed by the compression system that we designed. After many consultations with a guest lecturer on our simulations, we were advised to add a separate gas dehydration unit, specifically a triethylene glycol (TEG) unit with a glycol contactor and regenerator, in between our compression system and pipeline. By incorporating the advice we had received, we were able to reduce the water level to a ppm range suitable for EOR.
After each subgroup completed their simulation, our group reviewed the completed simulation to ensure that all streams were connected to the correct equipment and we finalized the process design. From there, our project manager led us through a basic HAZOP study by reviewing the equipment that we had used in each subgroup, identifying the potential hazards, the risks associated with them, and what we could do to mitigate the risks. Then, we went on to determine the cost of the equipment and raw materials. For each piece of equipment, we had to make note of the material used, size, and various cost indexes. Like the previous course, we gave a 60-minute presentation detailing the equipment and processes we chose for our ammonia plant.
Finishing a project of such magnitude in my academic career was a significant accomplishment. Overall, the senior design project left a huge impression on me, and gave me a new appreciation of the importance of teamwork and organization. Working in a large group emphasized the real value of clear communication to ensure that deadlines are being met and that everyone is on the right track, while fairly allocating tasks. The one major takeaway for me was to be confident enough to ask questions. Whether it be outside professionals or group members, it’s important to always ask questions — someone may just have the answer.
This article originally appeared in the "Emerging Voices" column in the January 2023 issue of CEP. Members have access online to complete issues, including a vast, searchable archive of back-issues found at www.aiche.org/cep.