3e. Mercury Controls

What is Mercury? 

Mercury is a shiny, silver-white metal that is a liquid at room temperature. Coal-fired power stations emit tiny amounts of gaseous mercury through chimneys. This mercury can combine with water in the atmosphere and fall back to earth in rain or mist. The inhalation of airborne mercury can be harmful to the nervous, digestive, and immune systems of humans. It can also negatively impact the lungs and kidneys. High doses may be fatal. 

Mercury is also harmful to the environment. It gets into the water systems harming fish, wildlife, and plant life.

Controlling Mercury Emissions

North Dakota’s lignite contains the element mercury. After combustion, the mercury is left in the precipitate, or solid material remaining in the boiler. The precipitate is treated with a process that allows the mercury to be absorbed by a carbon powder. The absorbed mercury is no longer harmful and is either buried in specialized pits with other precipitates, or used in commercial products such as sandblast media or road asphalt.