NETL Tests Effect of Sulfur Oxides on Mercury

	Evan Granite, left, a researcher in the Office of Research and Development at the Department of Energy’s National Energy Laboratory, and Albert Presto, a post-doctoral researcher, prepare an experiment at NETL’s packed bed reactor, which is used for research into capturing mercury, arsenic and selenium.

Fossil fuels such as coal contain trace levels of mercury. When the fuels are burned, mercury is released, with some going to the stack.

One way to remove the mercury from flue gases produced by combustion is to contact the gases with activated carbons, which are widely used for that purpose.

Activated carbon loses some of its effectiveness during the capture process because of sulfur oxides that are produced, particularly sulfur trioxide.

NETL researchers in the Office of Research and Development are conducting tests to gain better understanding of the impact of sulfur oxides on activated carbon’s ability to capture mercury.

Test results obtained at NETL and reported in the American Chemical Society journal, Environmental Science & Technology, suggest that mercury and sulfur oxides compete for the same binding sites on the surface of activated carbon. Even small concentrations of sulfur trioxide, as low as 20 parts per million, inhibit mercury capture by activated carbons in the bench-scale experiments.  

NETL studied mercury capture varying conditions of SO₂ and SO3 concentrations using a bench-scale packed bed reactor and simulated flue gas (SFG).  The final mercury concentration of the activated carbons is independent of the SO₂ concentration in the SFG, but the presence of SO3 inhibits mercury capture even at the lowest concentration tested.

NETL Researchers Study Effect of CO₂ on Coal Seam Sequestration

	Duane Smith, a researcher in NETL’s Office of Research and Development, studies data obtained from coal core samples analyzed in the CT scanner visible through the window.

Researchers are looking at various ways to keep carbon dioxide from getting into the atmosphere.

One option for storing carbon dioxide permanently is to inject it into coal seams where it would be trapped inside the coal.

Researchers in NETL’s Office of Research and Development are studying the effects of carbon dioxide injection into coal seams, and the implications for additional storage of carbon dioxide.

When carbon dioxide is injected into a coal seam,
it is sorbed – taken up by the coal through absorption or adsorption – and held.

Research performed at NETL on the effects of carbon dioxide sorption demonstrates that under some circumstances, sorption can cause the coal to swell, and make it more difficult for additional carbon dioxide to be stored.

However, NETL research also has shown that carbon dioxide sorption can cause fractures to develop in the coal, which would make the injection easier. This finding apparently has been confirmed by field tests around the world; in some cases, carbon dioxide injection caused the injectivity to increase.

NETL research into the effects of injection was recently selected by the Society of Petroleum Engineers to be highlighted to its worldwide membership.
The article "Influence of Shrinkage and Swelling of Coal on Production of Coalbed Methane and Sequestration of Carbon Dioxide" has been published in the Journal of Petroleum Technology, Volume 59, No.8, pages 74-76, August 2007.  The paper was originally presented at the society’s annual meeting.

NETL Assists Oilfield Center in Locating Wells, Methane Leaks

	NETL and RMOTC personnel evaluate a new helicopter-borne well finding technology at Naval Petroleum Reserve No. 3. Pictured from left to right are Kenny Colina, RMOTC; Roger Hall, RMOTC; Garret Veloski, NETL; Rick Hammack, NETL; and Vicki Stamp, RMOTC.

NETL researchers in the Office of Research and Development used the lab’s award-winning well-finding technology to help RMOTC (the Rocky Mountain Oilfield Testing Center) survey the Naval Petroleum Reserve No. 3 (NPR-3).

The reserve is a 15 square mile oilfield near Casper, Wyoming.

NETL used its SEQURE™ technology to acquire more than 1,500 line kilometers of magnetic and methane data. SEQURE is the only commercially available technology that can search vast areas for abandoned oil and gas reservoirs that could be used to permanently store carbon dioxide.

The technology acquires data during flyovers in a helicopter using boom-mounted magnetometers and a sensitive methane and light hydrocarbon detector. NETL modified the flight plan and instrument payload used previously for the highly successful 2005 SEQURE™ well finding survey at nearby Salt Creek Oilfield to improve the detection of wells with weak magnetic signatures.

In addition, the methane detection device was added to detect any leaking infrastructure in the 100-year old oilfield.

To evaluate the effectiveness of the helicopter survey, NETL scientists conducted a thorough ground-level magnetic and methane survey of a 100-acre test area within the NPR-3 survey area for comparison. A number of controlled leaks were also deployed and served as a test for the methane sensing instrument prior to conducting the main survey.

NETL will process the airborne data and provide RMOTC with GIS maps depicting anomalous magnetic features and methane plumes as overlays.

Initial maps using uncorrected magnetic data depict the location of numerous, weak, well-type anomalies, a preliminary indication that the survey was successful in this respect.

The importance of the SEQURE technology was recognized this year by R&D Magazine, which named SEQURE a winner of the R&D 100 Award given each year to the 100 most technologically significant new products to hit the market during the year.

This was the first time an R&D 100 Award was given to a technology developed for permanent storage of carbon dioxide.