Methane dissolution inside bulk or porous-medium-confined water at near-hydrate equilibrium conditions

Abstract

In this study, we perform a series of mass-balance-type calculations, in order to estimate the minimum volume of liquid water required to dissolve completely a single methane gas bubble, located inside different types of domains that are near or under hydrate equilibrium pressure/temperature conditions. We examine the case of methane bubble dissolution in the bulk, along with the cases of methane bubble dissolution within simple/regular networks of pores, where all pores have the same size. In our calculations, we consider experimental values for the equilibrium solubilities of methane in water, along the hydrate-forming line, as well as, values obtained from predictive tools that are based on different thermodynamic models. The effect of aqueous NaCl solutions on the results is also investigated. As a result of the relatively low solubility of methane in water, large volumes of water are required for complete dissolution of a methane bubble.

GRAPHICAL ABSTRACT

KEYWORDS:

• Gas hydrates
• gas dissolution
• methane solubility
• hydrate equilibrium
• porous medium

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

INT acknowledges partial support of this work by the project ‘NCSRD – INRASTES research activities in the framework of the national RIS3’ [grant number MIS 5002559] which is implemented under the ‘Action for the Strategic Development on the Research and Technological Sector’, funded by the Operational Program ‘Competitiveness, Entrepreneurship and Innovation’ (NSRF 2014-2020) and co-financed by Greece and the European Union (European Regional Development Fund).