TY - JOUR
T1 - Phase Behavior in Natural Gas + Glycol Systems, Part 1
T2 - Tri(ethylene glycol) (TEG) and Its Aqueous Solutions
AU - De Oliveira Cavalcanti Filho, Valderio
AU - Chapoy, Antonin
AU - Burgass, Rod
N1 - Funding Information:
Research presented in this paper was conducted in support of projects funded by Galp Energia, Linde AG, Petrobras, Petronas, Equinor, and Total, which is gratefully acknowledged. Valderio de O. Cavalcanti Filho acknowledges the financial support from Petrobras through his PhD Grant.
Publisher Copyright:
©
PY - 2021/11/11
Y1 - 2021/11/11
N2 - Glycols and their aqueous solutions are extensively utilized in the natural gas industry as hydrate inhibitors and desiccant agents. An increasing interest in new applications, such as subsea processing and carbon capture and storage (CCS) gas dehydration, requires evaluations for operations at high pressure. New measurements are presented for methane and a natural gas mixture (methane-ethane-propane-carbon dioxide) in tri(ethylene glycol) (TEG) and TEG aqueous solutions. Solubility measurements were carried out at pressures up to 40 MPa for temperatures T = (273.15 and 353.65) K. Water content data covers temperatures between (278.15 and 313.15) K at p = (6 and 12.5) MPa. In addition, water activities in such solutions are also reported. The experimental data were modeled with three different approaches: the simplified cubic-plus-association (sCPA), a Huron-Vidal Soave-Redlich-Kwong (SRK) equation coupled with the Non-Random Two-Liquid (NRTL) Gibbs energy (gex) expression (SRK/HV/NRTL), and the non-density-dependent approach to Peng-Robinson (PR/NDD). The SRK/HV/NRTL model was found wanting for correlating experimental methane solubility data, while the PR/NDD and sCPA were successful in describing the methane/TEG phase behavior but not TEG aqueous solutions. An alternative approach that includes a binary interaction parameter dependent on the liquid phase composition (xkij) gave fair to satisfactorily results, particularly in the case of sCPA. For the multicomponent system, sCPA-xkij has yielded more consistent predictions than PR/NDD-xkij, especially for total gas solubility. Overall, all the models have failed to give satisfactory results based only on binary parameters.
AB - Glycols and their aqueous solutions are extensively utilized in the natural gas industry as hydrate inhibitors and desiccant agents. An increasing interest in new applications, such as subsea processing and carbon capture and storage (CCS) gas dehydration, requires evaluations for operations at high pressure. New measurements are presented for methane and a natural gas mixture (methane-ethane-propane-carbon dioxide) in tri(ethylene glycol) (TEG) and TEG aqueous solutions. Solubility measurements were carried out at pressures up to 40 MPa for temperatures T = (273.15 and 353.65) K. Water content data covers temperatures between (278.15 and 313.15) K at p = (6 and 12.5) MPa. In addition, water activities in such solutions are also reported. The experimental data were modeled with three different approaches: the simplified cubic-plus-association (sCPA), a Huron-Vidal Soave-Redlich-Kwong (SRK) equation coupled with the Non-Random Two-Liquid (NRTL) Gibbs energy (gex) expression (SRK/HV/NRTL), and the non-density-dependent approach to Peng-Robinson (PR/NDD). The SRK/HV/NRTL model was found wanting for correlating experimental methane solubility data, while the PR/NDD and sCPA were successful in describing the methane/TEG phase behavior but not TEG aqueous solutions. An alternative approach that includes a binary interaction parameter dependent on the liquid phase composition (xkij) gave fair to satisfactorily results, particularly in the case of sCPA. For the multicomponent system, sCPA-xkij has yielded more consistent predictions than PR/NDD-xkij, especially for total gas solubility. Overall, all the models have failed to give satisfactory results based only on binary parameters.
UR - http://www.scopus.com/inward/record.url?scp=85115009445&partnerID=8YFLogxK
U2 - 10.1021/acs.jced.1c00313
DO - 10.1021/acs.jced.1c00313
M3 - Article
AN - SCOPUS:85115009445
SN - 0021-9568
VL - 66
SP - 4075
EP - 4093
JO - Journal of Chemical and Engineering Data
JF - Journal of Chemical and Engineering Data
IS - 11
ER -