NR2187

NEWS RELEASE                                                                                                    JANUARY 2016

Benefits of Sharing Air Pollution Information across Geographies and Applications

Large power plants in the developed countries were the main purchasers of air pollution control systems in the past.  This is no longer the case.  Developing countries are the big spenders in the power plant sector.  Other industries such as cement, waste-to-energy, steel and oil and gas are stepping up the investment to remove gas phase contaminants.

The innovations and insights are now scattered around the world.  In order to ensure that the value is shared, McIlvaine is taking several steps:

  • Strengthen the interface with Asian and African power plants who are making many difficult decisions.
  • Expand coverage of all the industrial applications.
  • Facilitate the transfer of information from industry to industry.

Changes have been made to the McIlvaine webinar format as part of the new focus:

  • Organization is by pollutant with segmentation by industry rather than the reverse.
  • Power point decision guides for various industry/pollutant combinations are maintained and available for reference during the webinars.
  • The webinars are focused on helping end users make decisions using the guides.
  • End user participants can ask questions which will be addressed in the discussion format.
  • Suppliers and various experts can submit information for consideration in the guides and can debate or discuss options during the webinars.
  • The guides are displayed and continually updated on the Air Quality Decisions.
  • The webinars are free of charge to everyone.  The decision guides and access to the Air Quality Decisions website is free to end users but by subscription only for others.

A webinar on February 11 will cover mercury control in all industries in all countries.  There will be seven slide decks available for reference and display during the meeting:

  • Pulverized coal with wet scrubbers
  • Pulverized coal without wet scrubbers
  • Coal gasification and IGCC
  • Cement
  • Sewage sludge incineration
  • Waste-to-energy
  • Other including steel, taconite mining, etc.

Anyone can submit data for consideration over the next three weeks.  End users and subscribers can request copies of the draft slide decks in advance.

Activated carbon improvements are important and are options for all the applications.  Bromine injection to oxidize mercury also has widespread application.  Mercury absorber modules are now being used in power, sewage sludge incineration and have potential for most applications.

The multi pollutant aspects of each application influence the mercury removal choice.  If wet scrubbers are used for acid gases, the bromine additive for mercury oxidation is the likely first choice.

The mercury emission limit is a major consideration.  Many industries in many countries are not constrained.  In others, the limit is 50 ug/Nm3.  This limit can often be met without special mercury reduction investment. The U.S. has led the way with limits approaching 3 ug/Nm3.  As a result, many of the latest innovations have occurred here.

The decisions are influenced by the ultimate fate of the captured mercury.  One aspect is mercury re-emissions from scrubbers.  Another is mercury in gypsum and scrubber sludge.  Dust with mercury laden activated carbon is another challenge.  There are some unique solutions which need further investigation.  Several waste-to-energy plants in Germany are utilizing two-stage scrubbers.  The first stage concentrates HCl and generates dirty 30 percent hydrochloric acid.  The mercury is removed with ion exchange resin.  The clean acid is then sold.

This process opens up a brand new opportunity which is the rare earth and precious metals recovery from flyash using acid leaching. 

Combining emission sources is another solution.  Municipal solid waste and sewage sludge can be utilized in cement kilns and coal-fired power plants. 

MSW gasification, cleanup and direct use as a turbine fuel is relatively costly.  On the other hand, using gasified dirty municipal waste as a reburn fuel in coal fired boilers has several benefits.  It replaces coal and reduces net greenhouse gases.  Injection above the primary firing zone reduces NOx.  The mercury in the gasified waste is removed along with the mercury in the coal in the main air pollution control system.

To register for the mercury webinar click on: Click here to register