Honors Theses
Date of Award
Spring 5-8-2026
Document Type
Undergraduate Thesis
Department
Chemical Engineering
First Advisor
Brenda Prager
Second Advisor
Mike Gill
Relational Format
Dissertation/Thesis
Abstract
This thesis presents the design and economic optimization of a Styrene Production Plant targeting a capacity of 100,000 tonnes/yr at a product purity of 99.8 wt%. The process relies on the dehydrogenation of ethylbenzene in a packed-bed reactor system. Downstream separation is achieved through a series of cooling, phase separation, and distillation operations to recover styrene while recycling unreacted ethylbenzene and recovering valuable byproducts.
A base case design was developed and evaluated using a process simulation software, Aspen Plus V14, and an economic analysis. Sensitivity analysis identified the styrene market price and ethylbenzene raw material cost as the dominant factors influencing the net present value (NPV). Because market conditions cannot be controlled, optimization efforts focused on reducing raw material consumption while maintaining production targets and styrene purity.
Key process improvements included reducing the ethylbenzene feed rate from 300 kmol/h to 186 kmol/h, optimizing reactor volumes, and increasing the low-pressure steam to ethylbenzene ratio. The distillation columns were also optimized through adjustments to reflux ratios, number of stages, operating pressures, and distillate-to-feed (D:F) ratios to achieve the desired product specifications.
As a result of these optimizations, the NPV improved significantly from an initial value of approximately -$351 M to -$25 M, demonstrating a 93% increase from the base case. In addition to economic improvements, process safety and environmental considerations were also evaluated to ensure the plant operated safely, met legal requirements, and protected both the employees, community, and the environment. Overall, this analysis presents a thorough approach to designing and optimizing a Styrene Production Process while maintaining a balance between economic performance, safety, and environmental concerns.
Recommended Citation
Hardenstein, Kaylee and Anderson, Amanda, "The Design and Optimization of a Styrene Production Plant" (2026). Honors Theses. 3584.
https://egrove.olemiss.edu/hon_thesis/3584
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.