ADVERTISEMENT

Tuning The State-Of-The-Art Numerical Simulator To Recover Energy From Methane Hydrates

With the ever-increasing demand for cleaner energy, natural gas is playing a growing role in the global energy mix replacing coal and oil to help transition into a future carbon-constrained world. Methane hydrates (MHs) have been considered as the potential future resource of energy due to its abundant resource volume of CH4 (20,000 trillion cubic meter) in nature.

MHs are stable at suitable low temperatures and high-pressure conditions. They are typically found at permafrost locations and offshore locations near the continental shelf. This resource volume is probably twice of the total oil and gas reserves on earth. Exciting R&D programs are ongoing in Japan, China, Korea, India, and the U.S.A., trying to exploit the potential of MHs for energy within the next 20 years.

ADVERTISEMENT
(Image republished with permission)

The numerical simulation of the production performance of MH reservoirs under different production techniques is an important tool, as it provides critical information on the production rate and duration of reservoir fluids (water and CH4 gas). It is practically the only method that is able to predict long-term production from MH reservoirs since most field tests are short in duration because of the hostile production environment and high capital investment.

To tackle this front, the state-of-the-art reservoir simulator of methane hydrate (TOUGH+Hydrate v1.5) was developed by the Lawrence Berkley National Laboratory to model the dynamic behavior of MH formation and dissociation together with the associated fluids production behavior in geological media accounting for all known physics (thermodynamics, heat transfer, fluids flow, phase change criteria). Such reservoir simulator tools though powerful in its efficiency, require validation against laboratory experimental data or field production data to install confidence in its predictions.

In this direction, a recent study faithfully duplicated the multi-stage MH formation process in an unconsolidated sandy medium in a 1.0 L reactor numerically by employing the T+H v1.5 simulator based on a history-matching technique. Simulation prediction of the system performance (pressure and temperature) achieved excellent agreement with the experimental observation. Their study reveals that the phase change behavior of MH formation and dissociation in the sandy porous medium is better represented by a kinetic reaction model rather than an equilibrium reaction model.

Moreover, from the simulation prediction, it is elucidated that the spatial distribution of hydrate (SH) in sandy medium inside reactor can be significantly heterogeneous varying from SH = 5% in the reactor center to SH = 65% towards the reactor boundary. This finding is a breakthrough, which improves our understanding of the process of MH formation both in terms of temporal and spatial distribution.

ADVERTISEMENT

These findings are described in the article entitled Numerical analysis of experimental studies of methane hydrate formation in a sandy porous medium, recently published in the journal Applied Energy. This work was carried out by Zhenyuan Yin, George Moridis, Hoon Kiang Tan and Praveen Linga. This is a collaboration work involving the Department of Chemical & Biomolecular Engineering in the National University of Singapore, Lawrence Berkeley National Laboratory, and Lloyd’s Register Singapore Pte. Ltd.

Comments

READ THIS NEXT

Beyond The Plastics…

It is clear that we cannot live without plastic anymore. Plastic has become an essential material for our life, from […]

Who Do Women Count As Allies In STEM?

People’s prototype for who scientists are is perhaps made most apparent in what has become a classic social science classroom […]

Shape Memory Polymers Could Program And Recover At Room Temperature

Shape memory polymers (SMPs) are a class of polymer that changes its shape with external stimuli, such as heat. The […]

Only One Type Of Science: European Scientists Denounce Use Of Homeopathy

Advances in medical science are being made all the time, just recently scientists managed to develop a treatment for HIV […]

The Challenge Of River Basin Monitoring

In the coming years, water management will face new challenges for several reasons. Global warming is reducing water availability, population […]

How Tropical Dry Forests Respond To Hurricane Damage

Global climate change is considered an emerging threat to the persistence and functioning of dry tropical ecosystems, which are the […]

Identifying The Impacts Of The El Niño And La Niña Events On Habitat Quality Of Chub Mackerel In The East China Sea

Published by Wei Yu and Xinjun Chen Shanghai Ocean University These findings are described in the article entitled Climate-induced habitat […]

Science Trends is a popular source of science news and education around the world. We cover everything from solar power cell technology to climate change to cancer research. We help hundreds of thousands of people every month learn about the world we live in and the latest scientific breakthroughs. Want to know more?