Post-Combustion CO2 Capture from an Industrial Power Plant Using Five Chemical Solvents: A Comparative TEA
Year: 2024
Type: article
Abstract: CO2 capture processes using five chemical solvents were modeled in Aspen Plus V.12.1 for the capture of over 90% CO2 from a 456 ton/hour split flue gas stream containing 12.02 mol% CO2 emitted by the Longview 780 MW power plant (West Virginia, USA). Since the flue gas contained 33.10 ppmv SO2 and 35.47 ppmv NO2, a gas polishing process, using deionized water (DIW), was included in the model for complete scrubbing of SO2 and NO2 from the raw flue gas before the CO2 capture process. The five chemicals used for CO2 capture included three amine-based solvents (ABs) (monoethanolamine (MEA), 2-amino-2-methyl-1-propanol (AMP), and (piperazine/methyldiethanolamine (PZ/MDEA)), and two amino acid-based solvents (AAs) (sodium glycinates (SGS) and potassium glycinates (PGS)). Since SGS and PGS exhibit phase separation, the CO2 capture processes followed two distinct pathways: Pathway (i) involved direct CO2 capture using all five solvents, and Pathway (ii) focused on bicarbonate nanomaterials production using only SGS and PGS. A Techno-economic assessment (TEA) of the CO2 capture processes was conducted and the corresponding process hydraulics and mass transfer characteristics were calculated. The simulation results revealed the following: (1) for Pathway (i), the levelized cost of CO2 capture (LCOC) for PGS was lower than that for SGS, MEA, AMP, and PZ/MDEA; (2) for Pathway (ii), PGS had a lower LCOC than SGS; (3) Pathway (ii) was more economically more favorable than Pathway (i); and (4) under the operating conditions used, the two-phase pressure drop values were negligible, and the liquid-side mass transfer coefficients (kL) were an order of magnitude smaller than gas-side mass transfer coefficients (kG), suggesting that the gas-liquid mass transfer resistance (1/kL) was in the liquid-side. Our techno-economic analysis (TEA) underscores the uniqueness of using AAs solvents in industrial CO2 capture, offering significant cost savings through the production of valuable bicarbonate nanomaterials.
Language: English
Subfield: Mechanical Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
OpenAlex ID: W4404603976