Activated Carbons for Mercury Removal

Mercury, a toxic and corrosive material, must be removed from various gas and liquid streams. Since it is always present in very low concentrations, adsorption processes are most suitable for mercury removal. Activated carbon serves as an excellent carrier for various impregnants, which physically react with the mercury and hold it within the adsorbent particles. Very high levels of purity can be attained because of the high mercury removal efficiencies attained by the adsorption process.

The NUCON technical manual for mercury removal processes can be seen at Mercury Adsorbents Design and Performance.

A general survey of methods of Mercury Control by Fixed Bed Adsorption indicates there are a wide variety of uses for this technology.

MERSORB^® mercury adsorbent products are used for removing mercury from gas phase hydrocarbons such as natural gas. Since mercury corrodes the aluminum heat exchangers used to liquefy natural gas, it must be removed before the low temperature condensation step. Mercury removal is also necessary to protect downstream equipment from corrosion such as compressors and pipelines. It is common to achieve a mercury concentration of <0.010 μg/Nm³ with this process.

Laboratory tests have been performed on several simulated gas streams and the results have been used as a basis for the design of mercury removal processes. They include off gas from mixed waste incineration, a plasma enhanced melter, ventilation of a hot cell, and a chemical munitions incineration process. The Laboratory Experiment Data Summary shows the results of these tests.