Particulate Carbon Emissions from ESPs During Injection of Powdered Mercury Sorbents: Updated Estimates Based on the U.S. EPA Report to Congress on Black Carbon

摘要

A previous analysis explored a broadrange of parameters and their potentialimpacts on unintended emissions ofsub-micron powdered activated carbon(PAC), injected into coal combustionflue gas to reduce mercury emissions,from electrostatic precipitators (ESPs).This present analysis updates theprevious analysis in several importantways, better aligning it with therecently released U.S. EPA Report toCongress on Black Carbon. The resultis a narrower range of estimates forpotential increases in emissions ofPM2.5 particulate carbon. Suchincreases are projected in associationwith current and anticipated new limitson mercury emissions from coal-firedpower generation and the use of PACinjection for controlling mercuryemissions. The principal uncertainty inthe projections is the unknown ESPcollection efficiency differentialbetween residual PM2.5 fromcombustion and PM2.5 PAC.