PhD Defence by Randi Neerup

Principal supervisor
Associate professor Philip Loldrup Fosbøl
DTU Chemical and Biochemical Engineering

Co-supervisor
Professor Georgios Kontogeorgis
DTU Chemical and Biochemical Engineering

Examiners
Professor Nicolas von Solms
DTU Chemical and Biochemical Engineering

Senior lecturer, Associate professor Helena Svensson
Lund University, Sweden

Senior researcher Niels Hemmingsen Schovsbo
GEUS, Denmark

Chairperson at defence
Senior Executive Officer Uffe Ditlev Bihlet
DTU Chemical and Biochemical Engineering

Popular science summary

Chemical CO2 capture is one of the technologies, which can reduce the CO2 emission from point sources such as biogas gas, cement production, and waste combustion. Thereby meeting the Danish goal of becoming net-zero emission free by 2050.
The drawbacks of this technology are high regeneration energy, solvent emission, and corrosion.
This dissertation is structured around three primary themes: energy consumption, solvent emissions, and CO2 corrosion.
The main goal of this Ph.D. study is to illustrate the potential of energy savings in the capture process by utilizing the CESAR1 solvent and employing advanced pilot process configurations. Another objective is to delve into the understanding of solvent emissions and impurities in the depleted flue gas and the generated CO2 stream from a capture plant. Additionally, the research aims to contribute novel insights into CO2 corrosion, specifically by exploring the solubility of FeCO3 in different media, including water, aqueous NaCl solutions, and HCl solutions. This endeavour is undertaken to enhance corrosion models.
Waste-to-energy facilities contribute to the increase in CO2 emissions. A cost-effective and energy-efficient method for capturing CO2 at the waste-to-energy plant, Amager Bakke, ARC, has been demonstrated. This was through the deployment of a newly built mobile capture plant. The CESAR1 solvent and various plant configurations were assessed. Energy reductions up to 24% were obtained compared to base case 30 wt% monoethanolamine (MEA). Low emissions of solvent related degradation products were measured in the flue gas released to the atmosphere as well as in the produced CO2 product stream.
The solubility of the CO2 corrosion product, FeCO3, was investigated. Precipitation of FeCO3 is considered as a protective barrier for further corrosion. It is therefore important to create new knowledge of the FeCO3 solubility in various systems.
The goal of this work is to identify the most effective solution, enabling ARC to establish a pilot plant initially and eventually develop a full-scale carbon capture plant. Furthermore, to contribute to understanding of solvent emissions and CO2 corrosion in the entire carbon capture, utilisation, and storage (CCUS) value chain.