Distribution of mercury in Indiana coals and its implications for mining and combustion

Status Start Date End Date Locations
completed Sep 1, 2002 Aug 31, 2004 Clay, Daviess, Dubois, Gibson, Greene, Knox, Parke, Spencer, Vigo
Director: Maria Mastalerz
Other Researchers:
Issue: The Clean Air Act authorized the U.S. Environmental Protection Agency to regulate mercury emissions from electric utilities. New rules are going into effect on mercury (Hg), a difficult element to remove from coal during conventional cleaning processes. The available data indicate that usually 25 to 50 percent of mercury can be removed, but the range of Hg removal is often unpredictable. It is important to identify coal seams and coal zones having the lowest mercury content.
Objective: 1) Develop a database of mercury content of Indiana coal seams that can be used by the coal and energy industries; 2) Investigate controls on mercury content to formulate a predictive model for the coal and energy industries to make decisions about mixing coals to meet the new mercury regulations; and 3) Investigate techniques of mercury removal from coal.
Approach: We will develop a database that includes the mercury content of the primary coal seams mined within Indiana. After determining the geological controls on mercury content in major coal seams of Indiana, we will incorporate these data. We will analyze approximately 300 new samples for mercury content and other chemical and physical attributes. We will also test geochemical techniques to isolate the important mercury-containing fractions in the coals.
Products: A detailed database of the composition of numerous representative samples of Indiana coal was produced. This database will permit delineation of low-mercury coal zones in Indiana and enable mapping of coal zones having desirable mercury concentrations. We will also identify factors that influence mercury concentration, to use as a predictive tool in further coal exploration and selective mining.
Benefits: This research helps the mining industry in Indiana find areas of low-mercury coal and to efficiently plan economic, environmentally sound mining techniques and coal cleaning strategies. Utilities can use the database of mercury distribution in Indiana coals to aid in planning their coal purchases. It will benefit both the Indiana coal industry and industries using Indiana coal in this time of changing regulations that are designed to reduce air and solid waste pollution.