How China Can Leapfrog. Mercury Emission Reductions. Sid Nelson Jr.

Transcription

1 How China Can Leapfrog Title of Slide the World in Mercury Emission Reductions Sid Nelson Jr.

2 Impressive Development Throughout China

3 But Ever-Increasing Pollution

4 Mercury from Power Plants

5 Chinese Coals Average ~50% Higher Hg China USA Average coal Hg content, ppm, dry basis. Various sources. The difference may be even greater.

6 Overview of the Mercury Problem Source: U.S. EPA

7 Effects Observed in Small Newborn Samples 2006 Jedryckowski, et al., Effects of Prenatal Exposure to Mercury on Cognitive and Psychomotor Function in One-Year-Old Infants: Epidemiologic Cohort Study in Poland, Annals Epidemiology 16: Marques, et al., Maternal mercury exposure and neuro-motor development in breastfed infants from Porto Velho Brazil Int J Hyg Environ Health, 210(1): Gao, et al., Prenatal exposure to mercury and neurobehavioral development of neonates in Zhoushan City, China, Environmental Research, 105: Suzuki, K., et al., Associations of neonatal neurobehavioral status with cord blood PCB, maternal hair mercury, and maternal fish intake in the Tohoku Study Of Child Development, Organohalogen Compounds, 69: Xue, et al., Maternal fish consumption, mercury levels, and risk of preterm delivery, Environmental Health Perspectives, 115(1):42. (U.S.)

8 In the U.S., Hg from Fish Lowers IQ Oken (2005): lowering Hg 50% raises IQ = 2 points Oken (2008): lowering Hg 50% raises IQ = 1.5 points Lederman (2008): lowering Hg 50% raises IQ = 2.5 points Oken, E., et al., Maternal Fish Consumption, Hair Mercury, and Infant Cognition in a U.S. Cohort, Environmental Health Perspectives, 113(10):1376, Oken, E., et al., Maternal Fish Intake during Pregnancy, Blood Mercury Levels, and Child Cognition at Age 3 Years in a US Cohort, Am J Epidemiol 167: , Lederman, et al., Relation between Cord Blood Mercury Levels and Early Child Development in a World Trade Center Cohort, Environmental Health Perspectives, 116(8):1085, 2008.

9 Fish MeHg Varies Directly with Deposited Hg in the fish Isotopically enriched Hg(II) (90.9% 202 Hg +2 ) was spiked into large, isolated lake sections Uptake monitored in zooplankton, benthic invertebrates, & fish We conclude that concentrations of spike MeHg in the food web of the mesocosms were directly proportional to the rates of Hg(II) loading. Orihel, et al., Experimental evidence of a linear relationship between inorganic mercury loading and methylmercury accumulation by aquatic biota, Environ. Sci. Technol. 41: 4952, 2007.

10 How Is Hg Done in the U.S.? ACI B-PAC H-PAC C-PAC Boiler ESP /FF 700F 300F Air Preheater Fly Ash Brominated Powdered Activated Carbon Injection (ACI) before the ESP

11 ACI System We have installed 10 systems Lances sticking into the ductwork 10-cm transport line & sold many millions of kgs of brominated carbons Silo to hold the PAC & blower(s) Delivering brominated PAC

12 Over 100 ACI Systems Sold Can be expensive for 90% (but micro-injection is not & is suited to plants without FGD) 55,000 MW of capacity

13 Leverage Hg Reductions from Scrubbers China USA Fraction of Power Plants with FGD

14 Many Chinese Coals Have Low Halogens High Cl Low Cl USGS preliminary data on 305 samples Vosteen, Chinese Low Chlorine Coals Need Bromine for Co-Benefit Mercury Capture, EUEC Conference, 2010.

15 Oxidize Hg(0) with CaBr 2 on Coal While wet scrubbers remove most of the Hg+2 from the flue gas, they remove essentially zero of the Hg(0) Adding a small amount of bromide to the coal can change Hg(0) to Hg+2 so the scrubber can remove it

16 Very Simple & Inexpensive Just drip a CaBr 2 salt solution onto the coal

17 Chinese Wet Scrubbers 100 Usually ~ 70% from ESP+FGD; But sometimes much less Guizhou Guizhou Guizhou Guangdong Shanxi Beijing (SCR) Wang, et al., Mercury emission and speciation of coal-fired power plants in China, Atmos. Chem. Phys., 10, , 2010.

18 Two More This one low Hg very low capture M e rc u ry R e d u c tio n Hebei Zhang et al., Mercury Emissions from Six Coal-Fired Power Plants in China Fuel Processing Technology, 1033, No SCR SCR On Ozone Season Wu, et al., Evaluation of mercury speciation and removal through air pollution control devices of a 190 MW boiler, Environmental Sciences, 227, 2010.

19 D Dombrowski (URS) et al., Near and Long Term Options for Controlling Mercury from Power Plants, MEGA Symposium, August 2008.

20 Luminant Monticello Station TX Lignite/PRB & LSFO + KNX CaBr2 - CaCl 2 not work, but CaBr 2 did: 30% 85% with ~100 ppm Benson, EERC, Richardson, URS, et al., Large-Scale Mercury Control Technology Testing for Lignite-Fired Utilities Oxidation Systems for Wet FGD, DOE NETL Hg Control R&D Program Review, 2006.

21 NRG Energy s Limestone Station Coal Blend with Wet Scrubber Tried CaBr2 with & without PAC Conditions %Hg Removal Baseline 30% 0.5 lb/mmacf 50% 100ppm CaBr2 70% ppm 80% ppm 90% 30% 70% with 100 ppm

22 We Energies Pleasant Prairie Plant with SCR - PRB coal - SCR - Wet FGD - KNX = CaBr2 55% 90% with ppm Rini, et al., Full-scale Test Results From a 600 MW PRB-fired Unit Using Alstom s KNX Technology for Mercury Emissions Control Air Quality VII, 2009.

23 Costs Are Tiny Compared to Other Pollutants Costs in the USA $/kw SO2: Scrubbers $250 NOx: SCR $150 PM: Fabric Filter $60 Hg: ACI Hg: CaBr2 $3 $1 Work underway on United Nations global legally binding instrument on mercury China can inexpensively lead the way

24 Take-Home Messages 1. Every year that China delays reducing Hg, it lower its IQ 2. Brominated activated carbon in the U.S., but can be expensive 3. Adding small amounts of CaBr 2 to the coal can result in significantly improved Hg co-reductions in FGD at many plants 4. Very simple, very cheap, and very cost-effective 5. With CaBr 2 on FGD (and micro-injection without FGD), China can leapfrog the U.S. & the world in Hg reductions