NETL Studies Methane Hydrate Decomposition at Molecular Level

	Evgeniy Myshakin, the lead investigator in the research using molecular-level simulations to study methane hydrate decomposition, views results of the simulations.

Collaborators at NETL and the University of Pittsburgh have used molecular-level simulations to obtain a better understanding of how methane hydrate decomposes when subjected to conditions typical of those anticipated in methane production scenarios.

Methane hydrate is a frozen substance in which methane (natural gas) molecules are encaged in a water lattice. It’s referred to as “fire in the ice.” Methane hydrate can occur in locations where the temperature is cold and the pressure is high, such as on and under the ocean floors and in and beneath polar permafrost regions. 

It has been estimated that methane hydrate may contain more carbon than all the coal, oil, and non-hydrate natural gas combined. Because of the huge volume of methane, NETL is studying methane hydrate as a possible source of energy and as a potential contributor to greenhouse gases in the atmosphere.

 The molecular level studies are just one part of NETL’s methane hydrate research which also involves reservoir-scale modeling and an active field and experimental program. A key finding of the molecular level research was the observation of transitory, partial hydrate structures at the decomposing hydrate interface. In the presence of methane molecules and at appropriate conditions, these structures could serve as potential nucleation centers for bulk hydrate reformation, which has been observed in reservoir-scale simulations of hydrate production and causes a reduction in gas production. Hydrate reformation is also being experimentally studied at NETL.

Improved understanding of this phenomenon could lead to better predictive reservoir-scale models.  An account of the molecular-level study recently appeared in The Journal of Physical Chemistry A. (Vol. 113, No. 10, 2009, pg. 1913ff.)

NETL’s Electroplating Process Improves Fuel Cell Performance

	The beaker contains a metal solution used for applying electroplated manganese-cobalt coatings to solid oxide fuel cell interconnect materials.

An electroplating technique developed by NETL researchers to apply a manganese-cobalt oxide layer on ferritic stainless steel interconnect materials could improve the performance of solid oxide fuel cells.

The research is part of NETL’s effort to achieve DOE goals for long term fuel cell performance research to inhibit degradation of fuel cell interconnect materials.

The first on-cell tests at NETL with manganese-cobalt coated ferritic stainless steel interconnect materials, known as T441, showed that the cell performance degraded by less than 1.5 percent after 600 hours of testing. Cell performance with uncoated T441 interconnect degraded about 20 percent during the same test period. 

Further optimization of the coating process and investigations of thermal-cycling effects on the interconnect coating are underway. 

The new electroplating process offers significant advantages in cost and ease of operations over other coating methods. 

This work was conducted in collaboration with Prof. Xingbo Liu’s research group at West Virginia University under the University Research Initiative program.

NETL Studies Effects of Operating Parameters on Plasma Reformer Quality

	This is a view looking down into the plasma reactor.

NETL researchers are investigating lower-energy plasmas as a means of reforming heavy hydrocarbons – diesel fuel – into hydrogen-rich synthesis gas for use by high-temperature fuel cells being developed in the Solid State Energy Conversion Alliance (SECA) program. 

One of the applications is a diesel-fueled auxiliary power unit for long-haul truck transportation.

The researchers conducted runs at Drexel Plasma Institute in a gliding arc vortex plasma reformer to investigate the effects of several key parameters on the liquid hydrocarbon reforming properties.

The NETL researchers used n-tetradecane as a model diesel fuel compound for this study.

Low temperature non-thermal plasmas are more energy efficient than thermal plasmas. NETL researchers believe the low-temperature plasmas can be a viable alternative to the catalytic process for reforming diesel.  

NETL Concept Integrates CO₂ Cycle From Generation to Deposition

	Vyacheslav Romanov adjusts a manometric apparatus used for experimental validation of NETL's novel carbon sequestration approach concept.

Having found that the CO₂ adsorption capacity of certain overburden materials is comparable to that of coal, NETL researchers conceived a novel carbon sequestration approach using waste materials generated during coal production.

An invited article about NETL’s unconventional carbon capture and sequestration concept applicable in shallow underground and surface coal mines appears within the Features section of the American Chemical Society publication Environmental Science & Technology (Vol. 43, No. 3, pg. 561ff.).

The concept is based on a nano-trapping mechanism within the overburden, and involves heating and then trapping CO₂ in nano-spaces between layers of overburden. This concept could facilitate development of new chemical engineering techniques capable of permanently trapping CO₂ at low ambient pressures in overburden. 

If power generation were co-located with coal extraction/preparation, carbon capture could be facilitated by a controlled sequential heating and cooling of these solids with the exhaust heat of combustion.

The method avoids logistical problems and potentially significant transportation costs of delivering captured CO₂ from a power generation station to a remote sequestration site, as well as limitations associated with carbon sequestration in unmineable seams of coals that have shown a propensity to swell as the coal matrix imbibes CO₂.  A feature article in the American Chemical Society publication describes the approach.