TY - JOUR
T1 - Particulate Matter Formation in Post-combustion CO 2 Capture Columns
T2 - Insights from Molecular Dynamics Simulations
AU - Mansurov, Ulan
AU - Shah, Dhawal
AU - Bazybek, Nardana
AU - Amouei Torkmahalleh, Mehdi
N1 - Publisher Copyright:
© 2018 American Chemical Society.
PY - 2018/12/20
Y1 - 2018/12/20
N2 - The recent socio-political and climate changes have sparked tremendous interest in developing effective CO 2 capture processes. Conventional post-combustion CO 2 capture (PCCC) processes employ aqueous monoethanolamine (MEA) as a solvent; however, one of the major problems in the PCCC columns is the loss of a significant amount of the solvent in the form of particulate matter (PM). In spite of its importance, the formation of PM in a PCCC column has been overlooked, until recently. We herein analyze the process of the PM formation at a molecular level by underlining interactions between the participating components. Molecular dynamics (MD) simulations were performed on different systems consisting of CO 2 and MEA, and also in the presence of other components and conditions that are typically present in a PCCC column. The simulation revealed the evolution of molecular clusters, which are in a separate phase than the gas present around, comprising all the gaseous MEA, SO 2 , and most of the CO 2 and water vapor. We found the nucleation rate of the formed PM to be in the order of 10 30 cm -3 s -1 for the studied systems. The presence of water vapor enhanced the growth of the clusters, although the structure remained largely unchanged. On the other hand, although SO 2 was all absorbed in the cluster, it did not alter the growth rate or the structure of the formed cluster. Interestingly, the results also showed formation of large molecular clusters even at a low degree of supersaturation because of strong CO 2 -water interactions. Taken together, the results are the first of the efforts to understand PM formation in a typical PCCC column based on molecular simulations, and the findings led to certain practical suggestions to reduce PM formation.
AB - The recent socio-political and climate changes have sparked tremendous interest in developing effective CO 2 capture processes. Conventional post-combustion CO 2 capture (PCCC) processes employ aqueous monoethanolamine (MEA) as a solvent; however, one of the major problems in the PCCC columns is the loss of a significant amount of the solvent in the form of particulate matter (PM). In spite of its importance, the formation of PM in a PCCC column has been overlooked, until recently. We herein analyze the process of the PM formation at a molecular level by underlining interactions between the participating components. Molecular dynamics (MD) simulations were performed on different systems consisting of CO 2 and MEA, and also in the presence of other components and conditions that are typically present in a PCCC column. The simulation revealed the evolution of molecular clusters, which are in a separate phase than the gas present around, comprising all the gaseous MEA, SO 2 , and most of the CO 2 and water vapor. We found the nucleation rate of the formed PM to be in the order of 10 30 cm -3 s -1 for the studied systems. The presence of water vapor enhanced the growth of the clusters, although the structure remained largely unchanged. On the other hand, although SO 2 was all absorbed in the cluster, it did not alter the growth rate or the structure of the formed cluster. Interestingly, the results also showed formation of large molecular clusters even at a low degree of supersaturation because of strong CO 2 -water interactions. Taken together, the results are the first of the efforts to understand PM formation in a typical PCCC column based on molecular simulations, and the findings led to certain practical suggestions to reduce PM formation.
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U2 - 10.1021/acs.energyfuels.8b02647
DO - 10.1021/acs.energyfuels.8b02647
M3 - Article
AN - SCOPUS:85057557674
SN - 0887-0624
VL - 32
SP - 12679
EP - 12688
JO - Energy and Fuels
JF - Energy and Fuels
IS - 12
ER -