Date of Award
December 2024
Document Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
Department
Chemical Engineering
First Advisor
Gautham Krishnamoorthy
Abstract
Topics in this dissertation provide strategies towards reaching carbon-neutral power generation.Chemical looping combustion (CLC) can generate electricity free from CO2 emissions. Its success relies heavily on the performance of solid oxygen carriers (OC) that circulate through the system. In chapter 1, a manufacturing method to produce low cost, attrition resistant, and recyclable OC is presented. Laboratory scale attrition and reactivity screening of twenty-eight different OC was performed. Small additions of sinter enhancers during manufacturing were found to be key in producing an attrition resistant OC. Recyclability of the OC was demonstrated by reconstituting the OC from attrited fines to reform an OC particle. The recycled particle was found to have similar properties as virgin OC with a cost of $70/tonne. Solvent systems are the most developed CO2 capture technology today. In order to be economical, they need high-capacity factors. They are also prone to solvent loses from sub-micron particulate in the flue gases. Sub-micron particulate promoted by alkali species in the boiler fuel also leads to fouling of boiler heat transfer surfaces and reduced capacity factors of the plant and likewise the CO2 capture system. Chapter 2 describes the investigation of sorbent injection to capture alkali vapor species from furnace gases at high temperatures to minimize alkali aerosol formation. A CFD and capture kinetics model was developed. Alkali capture of 69% was measured and sorbent injection was successful in reducing boiler fouling and emissions of sub-micron aerosols. Firm power generators have a role in the decarbonization of the power grid to reduce overall system cost, however their economics are in jeopardy as the share of renewable energy grows. Long-term energy storage can be a mitigating factor. In chapter 3, a hybrid process that includes an electrolyzer, reformer, and H2 and O2 storage to function as long-term energy storage which produces operating costs savings while also producing decarbonized H2 was assessed. Energy storage dispatch optimization calculations were performed that minimized the levelized cost of hydrogen. The results showed that the hybrid process can supply decarbonized H2 for less than $2/kg and provide economic benefits to a collocated power plant.
Recommended Citation
Koenig, Aaron, "Methods And Process Designs For Improving The Operations And Economics Of Energy Storage And Carbon Dioxide Capture Systems" (2024). Theses and Dissertations. 6541.
https://commons.und.edu/theses/6541