More Mercury Control Options Available - Hot Topic Conclusion Yesterday

Lots of new information about mercury control was conveyed in the Hot Topic Hour yesterday.

Steve Derenne of We Energies updated the group on the TOXECON operation at Presque Isle. Over 90 percent mercury removal is being consistently achieved with either Norit Hg at 1.7 lb/macf or Norit LH at 1.0 lbs/macf. There is some sensitivity to temperature, and usage will go up in the summer. The mercury in the raw coal varies but is pretty average at a little over 100 lbs/yr. Calculated costs are $62,000/lb of Hg captured. The variable portion is $11,000/lb of Hg, but since the baghouse also removes particulate, the system is more cost effective than these numbers imply.

The combination of Trona and PAC to achieve SO₂ removal is slightly better than Trona by itself.  Injecting LOI ash at high loadings only achieves 50 percent mercury removal. The combination of LOI ash and PAC achieves only about the same results as the PAC alone. There are some minor dusting problems but the system is otherwise operating well.

Larry Bool of Praxair told the group that you can make your own activated carbon on site using the plant’s coal. An entrained flow reactor produces the activated carbon and syngas. The gas is then reinjected in the boiler. The carbon can then be used in a standard ACI system. The system is ready to demonstrate at full scale. The savings are projected at 40 percent less than purchased activated carbon.

Giselle Sherman of Corning described an activated carbon honeycomb which is anticipated to remove 90 percent of the mercury. It would be installed after the ESP or fabric filter. As a result it is not impacted by SO₃ flue gas conditioning. It is anticipated to be applicable to all coals. Additional field test demonstrations this year will focus on measuring the lifetime of the honeycomb along with efficiency.

Stratos Tavoulareas of J-Power EnTech Inc. explained the ReACT system for simultaneous NO_x, SO_x, and mercury removal. The activated coke pellets move down through the absorber and then are conveyed to a regenerator. The by-product is sulfuric acid or gypsum. One of the strengths is the very high removal.

At Isogo #1, a 600 MW unit, SO₂ is 0.002-0.012 lbs/MMBtu, NO_x is 0.015 lbs/MMBtu and particulates are as low as 0.001 lbs/MMBtu. These are cleanliness levels which are acceptable for introduction into a CO₂ scrubber. A pilot unit operating at Valmy Station of Sierra Pacific was successful. Detailed results will be presented at the Mega Symposium.

Bob Crynack and Luke Wilkinson of Indigo Technologies discussed the ability of the agglomerator to protect an ACI user from triggering NSR. Activated carbon is very difficult to collect. A 500 MW unit would need to capture 99 percent of the activated carbon to ensure that particulate does not increase to the NSR trigger point. Addition of the agglomerator to a conventional ESP results in a net reduction rather than an increase in particulate, even with high rates of ACI injection.

More than 90 percent mercury removal is achieved with the Multi Air Pollutant System (MAPS). The heart of the system is a conditioning, sorbent injection and agglomerating section which reduces the flue gas temperature to 140-160°F followed by introduction of hot gas to bring the temperature back up to 190-210°F. A system is successfully operating in Poland.

Biographies and pictures of speakers are shown at Bios and Photos of Speakers

The individual power points can be immediately viewed in the Mercury Decision Tree using the following links.

Giselle Sherman - Corning

Continuing Decision Process For: Other Technologies

Activated Carbon Honeycomb
subscriber/Tree/DescriptionTextLinks/Corning Inc Giselle Sherman Hot Topic Hour April 24, 2008.pdf

Steve Derenne – We Energies

Continuing Decision Process For: TOXECON

 TOXECON Operational Update

http://www.mcilvainecompany.com/Mercury_Decision_Tree/subscriber/Tree/DescriptionTextLinks/Steve Derenne - We Energies - Hot Topic Hour April 24, 2008.htm

Bob Crynack and Luke Wilkinson - Indigo

Continuing Decision Process For: Products

Mercury Capture Using Indigo's Agglomerator and MAPS Technologies, presented by Bob Crynack and Luke Wilkinson, Indigo Hot Topic Hour April 24, 2008.

http://www.mcilvainecompany.com/Mercury_Decision_Tree/subscriber/Tree/DescriptionTextLinks/Indigo, Luke Wilkinson and Bob Crynack presentation - Hot Topic Hour April 24, 2008.htm
 

E. Stratos Tavoulareas – J-Power EnTech, Inc.

Continuing Decision Process For: Products

A Commercial Multi-pollutant Control Technology: ReACT (Regenerative Activated Coke Technology) presented by E. Stratos Tavoulareas, J-Power EnTech, Inc., Hot Topic Hour April 24, 2008

http://www.mcilvainecompany.com/Mercury_Decision_Tree/subscriber/Tree/DescriptionTextLinks/ReACT Presentation McIlvaine April 24 2008 final.pdf
 

Larry Bool - Praxair

Continuing Decision Process For: Products

On-Site Production of Activated Carbon for Hg Control

http://www.mcilvainecompany.com/Mercury_Decision_Tree/subscriber/Tree/DescriptionTextLinks/praxair 4-24-08 hot topics.pdf