Multi-well strategy for gas production by depressurization from methane hydrate-bearing sediments

by Terzariol, M, and Santamarina, J. C
Article Year: 2021 ISSN: ISSN 0360-5442 DOI: https://doi.org/10.1016/j.energy.2020.119710

Bibliography

Terzariol, M., and Santamarina, J. C. (2021). Multi-well strategy for gas production by depressurization from

methane hydrate-bearing sediments. Energy, Volume 220, 119710, ISSN 0360-5442,

 

Abstract

Hydrate-bearing sediments are a potential source of energy. Depressurization is the preferred production
method in mechanically stable and highly permeable sandy reservoirs. The goal of this study is to
develop closed-form analytical solutions for multi-well depressurization strategies and to explore the
synergistic interactions among wells. The key variables are the aquitard and sediment permeabilities, the
reservoir layer and aquitard thicknesses, and water pressures in the far-field, at phase transformation and
at the wells. These variables combine to define two governing dimensionless ratios (for permeability and
fluid pressure), and a characteristic length scale lsed. Proposed solutions show that synergistic multi-well
strategies dissociate a larger hydrate volume than an equal number of individual wells working independently.
The optimal distance between wells increases: (1) with the length scale lsed, (2) for tighter
aquitards, (3) for lower well pressure and when the original water pressure of the reservoir is close to the
dissociation pressure, and (4) when both the aquitard and the reservoir are thick. Implications extend to
both vertical and horizontal wells. The proposed closed-form solutions expedite design and economic
analyses and allow the fast comparison of potential production scenarios.

Keywords

Multi-well hydrates gas production methane Sediments energy