Insights into kinetic inhibition effects of MEG, PVP, and L-tyrosine aqueous solutions on natural gas hydrate formation
- PDF / 1,305,956 Bytes
- 14 Pages / 595.276 x 790.866 pts Page_size
- 26 Downloads / 148 Views
ORIGINAL PAPER
Insights into kinetic inhibition effects of MEG, PVP, and L‑tyrosine aqueous solutions on natural gas hydrate formation Amir Saberi1,2 · Abdolmohammad Alamdari1 · Ali Rasoolzadeh1 · Amir H. Mohammadi3 Received: 2 November 2019 © The Author(s) 2020
Abstract It is necessary to understand all the prerequisites, which result in gas hydrate formation for safe design and control of a variety of processes in petroleum industry. Thermodynamic hydrate inhibitors (THIs) are normally used to preclude gas hydrate formation by shifting hydrate stability region to lower temperatures and higher pressures. Sometimes, it is difficult to avoid hydrate formation and hydrates will form anyway. In this situation, kinetic hydrate inhibitors (KHIs) can be used to postpone formation of gas hydrates by retarding hydrate nucleation and growth rate. In this study, two kinetic parameters including natural gas hydrate formation induction time and the rate of gas consumption were experimentally investigated in the presence of monoethylene glycol (MEG), L-tyrosine, and polyvinylpyrrolidone (PVP) at various concentrations in aqueous solutions. Since hydrate formation is a stochastic phenomenon, the repeatability of each kinetic parameter was evaluated several times and the average values for the hydrate formation induction times and the rates of gas consumption are reported. The results indicate that from the view point of hydrate formation induction time, 2 wt% PVP and 20 wt% MEG aqueous solutions have the highest values and are the best choices. It is also interpreted from the results that from the view point of the rate of gas consumption, 20 wt% MEG aqueous solution yields the lowest value and is the best choice. Finally, it is concluded that the combination of PVP and MEG in an aqueous solution has a simultaneous synergistic impact on natural gas hydrate formation induction time and the rate of gas consumption. Furthermore, a semi-empirical model based on chemical kinetic theory is applied to evaluate the hydrate formation induction time data. A good agreement between the experimental and calculated hydrate formation induction time data is observed. Keywords Gas hydrate · Clathrate hydrate · Natural gas · Kinetic hydrate inhibitor (KHI) · Induction time · Kinetics List of symbols MEG Monoethylene glycol K Kelvin KHI Kinetic hydrate inhibitor PEO Polyethylene oxide PVCap Polyvinylcaprolactam Edited by Yan-Hua Sun * Amir H. Mohammadi [email protected] 1
Department of Natural Gas Engineering, School of Chemical and Petroleum Engineering, Shiraz University, Shiraz 71345, Iran
2
Department of Process Engineering, National Iranian Gas Company (NIGC), South Pars Gas Complex (SPGC) Phases 4&5, Bushehr 75391/311, Iran
3
Discipline of Chemical Engineering, School of Engineering, University of KwaZulu-Natal, Howard College Campus, King George V Avenue, Durban 4041, South Africa
PVP Polyvinylpyrrolidone rpm Round per minute SNG Synthetic natural gas THI Thermodynamic hydrate inhibitor A1–A5 Optimized p
Data Loading...
