University of Edinburgh
Pilot-scale testing of dynamic operation and measurement of interfacial wave dynamics in post-combustion carbon dioxide capture.
Degree: PhD, 2018, University of Edinburgh
Flexible carbon capture and storage (CCS) has the potential to play a significant part in the decarbonisation of electricity generation portfolios which have significant penetration from intermittent renewable sources. Post-combustion capture (PCC) with amine solvents is a mature technology and is currently the state-of-the-art for CO2 emissions reduction from power stations. However, knowledge of the dynamic capture process is currently limited due to a dearth of dynamic datasets which reflect real plant operation, lack of a robust in-situ solvent analysis method for plant control and uncertainty about how changing plant design affects the response to dynamic operations. In addition, the nature of interfacial gas-liquid dynamics inside the absorber column are not well known and rely on correlations for effective mass transfer area and liquid holdup which may have uncertainties of up to +/- 13%. This could result in absorption columns being improperly sized for CCS operations. Two pilot-scale test campaigns are implemented in order to gain an understanding of how the capture plant responds to dynamic operations, the first on natural gas combined cycle (NGCC)-equivalent flue gas, the second on pulverised coal (PC)-equivalent. Changes in flue gas flow rates and steam supply which are designed to be representative of PCC operation on real NGCC and PC plant are implemented, using 30%wt monoethanolamine (MEA) as absorbent in both cases. Dynamic datasets are obtained for 5 scenarios with NGCC and 8 with PC flue gas. The test campaigns are carried out using two separate pilot-scale facilities and highlight the effect of plant design on hydrodynamics and hence, the response of the capture plant to dynamic operations. Finally, a novel solvent sensor is used to demonstrate, for the first time, control of the capture facility using in-situ measurements of solvent composition, combined with knowledge of test facility hydrodynamics and response times. Results from the pilot-scale test campaign are then used along with a mathematical NGCC capture plant scale up to investigate the potential effects of dynamic operations on total yearly CO2 emissions and the associated environmental penalties, depending on CO2 price. Manufacturers of column internals for CCS often rely on computational fluid dynamic (CFD) software tools for design, but existing commercial codes are unable to handle complex two-phase flows such as those encountered in the absorber column of a CO2 capture plant. An open-source direct numerical simulation (DNS) tool which will be capable of rigorously modelling two-phase flow with turbulence and mass transfer has been developed and could eventually replace the empirical methods currently used in packing design. The DNS code requires validation by experiment. For the purpose of validation a dual-purpose wetted-wall column is constructed, which in addition to mass transfer measurements can be used to determine liquid film thickness using an optical method. Measurements of average film thickness, wave amplitude,…
Subjects/Keywords: carbon capture and storage; energy systems; flexibile CO2 capture; model validation
to Zotero / EndNote / Reference
APA (6th Edition):
Tait, P. (2018). Pilot-scale testing of dynamic operation and measurement of interfacial wave dynamics in post-combustion carbon dioxide capture. (Doctoral Dissertation). University of Edinburgh. Retrieved from http://hdl.handle.net/1842/29544
Chicago Manual of Style (16th Edition):
Tait, Paul. “Pilot-scale testing of dynamic operation and measurement of interfacial wave dynamics in post-combustion carbon dioxide capture.” 2018. Doctoral Dissertation, University of Edinburgh. Accessed October 15, 2019.
MLA Handbook (7th Edition):
Tait, Paul. “Pilot-scale testing of dynamic operation and measurement of interfacial wave dynamics in post-combustion carbon dioxide capture.” 2018. Web. 15 Oct 2019.
Tait P. Pilot-scale testing of dynamic operation and measurement of interfacial wave dynamics in post-combustion carbon dioxide capture. [Internet] [Doctoral dissertation]. University of Edinburgh; 2018. [cited 2019 Oct 15].
Available from: http://hdl.handle.net/1842/29544.
Council of Science Editors:
Tait P. Pilot-scale testing of dynamic operation and measurement of interfacial wave dynamics in post-combustion carbon dioxide capture. [Doctoral Dissertation]. University of Edinburgh; 2018. Available from: http://hdl.handle.net/1842/29544