Mercury Oxidation Challenges

To improve the mercury capture co-benefit of air quality control devices and activated carbon, power plants often first treat the flue gas with halides in order to oxidize the Hg and improve overall mercury capture in wet scrubbers or with PAC products.

While  the  addition  of  these  halides  to  the  coal  feed does  indeed  augment  the  mercury  oxidation,  there  are inherent  issues  and  limitations  to  these  systems:

  • Halide additions at typical furnace  temperatures  (>  2000º F)  generate acid gases that corrode the balance of the plant.
  • Plants using  halides  often  have  to  replace  their Air  Heater  baskets  in  just  12–24  months  (in  typical use  AH  Baskets  can  last  up  to  5  years!).
  • Replacing corroded  AH  baskets  results  in  expensive, unscheduled  and  unplanned  downtime  for  a  plant.
  • Halides also contaminate wastewater discharge; regulations for which are currently expanding.

Avoid Unscheduled Outages at Your Power Plant and Save Money in the Process

How It Works

Plant corrosion typical of halide use

EES Corp’s AS-HgOx product augments the oxidation of mercury and improves the co-benefit of the plant’s air quality control devices, but without the corrosive gases and damage to the balance of the plant.

  • EES Corp’s AS-HgOx product promotes oxidation of Hg via chemistry on the particle surface.
  • AS-HgOx is  injected  downstream  of  the  boiler, at much cooler flue-gas  temperatures  (just  300–600 degrees F) than halides, via a typical dry sorbent injection system.
  • AS-HgOx  is  ideal  for  those  plants  now  utilizing halide coal treatments that  are
    • Equipped with Wet FGD SO2 Scrubbers
  • Like  many other successful EES Corp products, AS-HgOx is  built on the company’s proprietary and proven amended-substrate platform.

Corrosion Free Hg Oxidation -The Clear AS-HgOx Advantage

AS-HgOx  does  not  generate  the  damaging  halogen gases,  which  also  means:

  • There is  no  change  in  the  flue  gas  environment;
  • There are  no  highly  corrosive  gases;
  • There is  no  increased  concentration  of  existing trace acid gases (HCl); and,
  • Ultimately,no  corrosive  damage  to  the plant,  putting  an  end  to  expensive, unscheduled  outages.

AS-HgOx is as effective as the typical halogens in oxidation performance while costing the same as Calcium Bromide, and even less than Calcium Chloride or iodine additives.