Mercury Sorbent HX™ - A Patented Advancement in the Application of Sorbents for MATS Mercury Compliance

摘要

BASF's Mercury Sorbent HX™ is a brominated mineral sorbent enabling a low carbon-in-the-fly-ash solution for mercury MATS compliance. A patented, blended composition of surface treated brominated kaolin and activated carbon is balanced to achieve both mercury capture and preserved fly ash value in a total cost competitive manner. A Southern Company coal-fired electricity generating unit (EGU) in the Southeast United States, evaluating their options for mercury MATS compliance, investigated the use of their existing particulate collection equipment in conjunction with mercury sorbent injection. Their serial arrangement of two electrostatic precipitators (ESP), one on either side of the air heater, required a sorbent that could achieve MATS compliant mercury emissions within the existing constraints on stack opacity even when injected into a nominally low-ash flue gas in which the sorbent constituted an exaggerated proportion of the particulate stream. Mercury Sorbent HX™, as a low-carbon technology, successfully controlled stack mercury emissions to MATS compliant levels within the imposed particulate collection operating constraints. Mercury Sorbent HX™ has been demonstrated in several utilities' technology screening trials to have achieved controlled mercury emissions of less than 1 lb/TBtu. Petrographic analysis showed that a concrete whose portland cement content was replaced by 20%-wt Class C fly ash, with a 1%-wt Mercury Sorbent HX™ content, satisfied typical requirements for concrete air, specific surface area, and spacing factor. Einlehner Abrasion testing showed Mercury Sorbent HX™ to be much less abrasive than standard powdered activated carbon.