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A new integrated hybrid system for post-combustion CO2 capture involving a pre-concentrating membrane and solvent-based absorption was designed, fabricated and tested at a 0.1 MWth pilot-scale CO2 capture unit using coal-derived flue-gas. The tests were performed with a proprietary solvent and 30 wt% mono-ethanolamine (MEA). The pre-concentrating membrane increased inlet CO2 concentrations in the flue gas from 14 vol% to up to 28 vol%., increasing the driving force for mass transfer of CO2 from the gas-phase to the solvents for higher rich carbon loadings in the absorber. With enhanced mass transfer, lower liquid circulation rates for the hybrid process (L/G = 3 compared to 5 for solvent-based only process) and the resultant sensible heat reduction contributed to specific reboiler heat duty savings of about 30%. The additional electrical energy consumption from auxiliary equipment in the hybrid process such as the vacuum pump, however, contribute to lower the total energy benefit for the process.

The quantification of atmospheric gases with small unmanned aerial systems (sUAS) is expanding the ability to safely perform environmental monitoring tasks and quickly evaluate the impact of technologies. In this work, a calibrated sUAS is used to quantify the emissions of ammonia (NH3) gas from the exit stack a 0.1 MWth pilot-scale carbon capture system (CCS) employing a 5 M monoethanolamine (MEA) solvent to scrub CO2 from coal combustion flue gas. A comparison of the results using the sUAS against the ion chromatography technique with the EPA CTM-027 method for the standard emission sampling of NH3 shows good agreement. Therefore, the work demonstrates the usefulness of sUAS as an alternative method of emission measurement, supporting its application in lieu of traditional sampling techniques to collect real time emission data.

Corrosion studies were carried out on metal coated and noncoated carbon steel as well as stainless steel in a pilot-scale post-combustion CO2 capture process. Aqueous 30 wt % monoethanolamine (MEA) solvent was used without any chemical additive for antioxidation to examine a worst-case scenario where corrosion is not mitigated. The corrosion rate of all carbon steels was almost zero in the absorber column and CO2 lean amine piping except for Ni-coated carbon steel (