Multi-Pollutant Emissions Control: Pilot Plant Study of Technologies for Reducing Hg, SO3, NOx and CO2 Emissions

Technical Report · Wed Aug 31 04:00:00 EDT 2005

DOI:https://doi.org/10.2172/896681· OSTI ID:896681

Fenger, Michael L ^[1]; Winschel, Richard A

---

1. Consol Energy Inc

A slipstream pilot plant was built and operated to investigate technology to adsorb mercury (Hg) onto the existing particulate (i.e., fly ash) by cooling flue gas to 200-240 F with a Ljungstrom-type air heater or with water spray. The mercury on the fly ash was then captured in an electrostatic precipitator (ESP). An alkaline material, magnesium hydroxide (Mg(OH){sub 2}), is injected into flue gas upstream of the air heater to control sulfur trioxide (SO{sub 3}), which prevents acid condensation and corrosion of the air heater and ductwork. The slipstream was taken from a bituminous coal-fired power plant. During this contract, Plant Design and Construction (Task 1), Start Up and Maintenance (Task 2), Baseline Testing (Task 3), Sorbent Testing (Task 4), Parametric Testing (Task 5), Humidification Tests (Task 6), Long-Term Testing (Task 7), and a Corrosion Study (Task 8) were completed. The Mercury Stability Study (Task 9), ESP Report (Task 11), Air Heater Report (Task 12) and Final Report (Task 14) were completed. These aspects of the project, as well as progress on Public Outreach (Task 15), are discussed in detail in this final report. Over 90% mercury removal was demonstrated by cooling the flue gas to 200-210 F at the ESP inlet; baseline conditions with 290 F flue gas gave about 26% removal. Mercury removal is sensitive to flue gas temperature and carbon content of fly ash. At 200-210 F, both elemental and oxidized mercury were effectively captured at the ESP. Mg(OH){sub 2} injection proved effective for removal of SO{sub 3} and eliminated rapid fouling of the air heater. The pilot ESP performed satisfactorily at low temperature conditions. Mercury volatility and leaching tests did not show any stability problems. No significant corrosion was detected at the air heater or on corrosion coupons at the ESP. The results justify larger-scale testing/demonstration of the technology. These conclusions are presented and discussed in two presentations given in July and September of 2005 and are included in Appendices E and F.

• Research Organization: Consol Energy Inc
• Sponsoring Organization: USDOE
• DOE Contract Number: FC26-01NT41181
• OSTI ID: 896681
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
20 FOSSIL-FUELED POWER PLANTS
ADSORBENTS
AIR POLLUTION CONTROL
BITUMINOUS COAL
CARBON DIOXIDE
CORROSION
ELECTROSTATIC PRECIPITATORS
FLUE GAS
FLY ASH
FOSSIL-FUEL POWER PLANTS
MAGNESIUM HYDROXIDES
MERCURY
NITROGEN OXIDES
PILOT PLANTS
SULFUR TRIOXIDE
WASTE PRODUCT UTILIZATION