Date of Award
January 2023
Document Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
Department
Energy Engineering
First Advisor
Xiaodong Hou
Abstract
This dissertation explores the potential use of potassium carbonate (K2CO3) supported adsorbents for large-scale carbon dioxide (CO2) capture processes. The post-combustion carbon capture process, which operates independently of the upstream fuel combustion process and the CO2 partial pressure in the flue gas, is emphasized for its integration into conventional coal-fired power plants without extensive modifications. While mature aqueous amine facilities are the industry standard, drawbacks in the predominant monoethanolamine (MEA) technology, such as high energy dissipation and oxidative degradation, motivate the exploration of adsorbent-based processes.Various adsorbents, including K2CO3-supported ones, are considered promising due to their high theoretical CO2 capture capacity and lower energy requirements for regeneration. However, challenges in distributing K2CO3 on support materials, leading to decreased exposure of active sites, must be addressed. To fill knowledge gaps, three hypotheses are formulated, focusing on optimizing synthesis methods, utilizing lignite for enhanced adsorbent value, conducting techno-economic evaluations, and examining kinetic and transport phenomena in fixed-bed columns. Six primary studies are conducted to test these hypotheses:
- Synthesis of a novel micro-spherical adsorbent using spray drying after leaching with Humic Acid (HA) and polyethyleneimine (PEI) to assess morphology and capture capabilities.
- Further development of adsorbent synthesis methodology, evaluating the impact of chemical activation on CO2 capture capacity.
- Evaluation of cyclic performance at the bench scale to assess scalability.
- Techno-economic analysis of the adsorbent manufacturing process and its integration into a coal power plant, providing insight into capture costs.
- Prediction of adsorption behavior through the study of adsorption and carbonization kinetics under different operating conditions.
- Development of a breakthrough model to predict mass transfer characteristics during adsorption, enhancing understanding of CO2-adsorbent interaction.
Key findings include the optimization of synthesis parameters for improved CO2 capture, the value of chemical activation in enhancing capacity, insights into cyclic performance limitations, and sensitivity of capture cost to the adsorbent sale price. The dissertation contributes valuable insights into the potential commercial scalability of K2CO3-supported adsorbents for CO2 capture.
Recommended Citation
Bellal, Abdelmalek, "Synthesis Of A Low-Cost And High-Performance Micro-Spherical Adsorbent For CO2 Capture: Performance Evaluation, Up-Scaling Assessment, Adsorption Kinetic, And Numerical Simulation" (2023). Theses and Dissertations. 5665.
https://commons.und.edu/theses/5665