NEWS RELEASE                                                                                        August 2019

Coal Fired Power Plant Decisions locates the Critical Insights Lost in the Wilderness of Available Knowledge

A millennium before Columbus proved that the earth was not flat a number Greek scholars knew it was round. History is filled with important knowledge which disappears at least temporarily. This has been true for coal fired power plant combust, flow and treatment (CFT) technologies. Let’s take FGD scrubbers as an example.


Year Invented and Location

Years Lost

Rediscovery and Circumstance

Venturi Scrubber

1890 - Austrian patent for coal gas scrubber


1950 Johnstone
U of Illinois

Turbulent Pool Scrubber

1900 - AAF Rotoclone

1960 - U.S. Navy Key West - Clam Shells

20 (maybe not lost but not utilized by power plants)

Chiyoda 121 Scrubber 1980s

Rod Deck Scrubber

1963 - Environeering

Rejected by Acquirer in favor of spray tower

Andritz Rod   Scrubber 2010

MEL Natural Oxidation Venturi Scrubber

Dravo Corp  

Not utilized since the 1970s

Could be a winner due to toxic metals

Two Stage Scrubber with HCl and REE Recovery

1970   United Engineers,   Environeering, Philadelphia Electric

40 years before REE recovery became important

This option should be prioritized over flyash landfills

Environeering prided itself on acquiring many scrubber patents. Most applications had to take into account the prior art of Johnstone, a university professor. Later research by the McIlvaine Company uncovered an Austrian patent vintage 1890 that would have invalidated the Johnstone patent.

When Environeering and its partner Combustion Engineering commenced designing the world’s first commercial limestone FGD system the only relevant experience to be found was a turbulent pool scrubber on a fuel oil fired boiler at a navy base in Key West. The calcium source was ground seashells. It is very likely that Chiyoda was not aware of this small installation when it invented a turbulent pool scrubber used presently in a number of power plants.

The original Environeering/CE design used marbles but a rod deck improvement was provided after a few years. Ironically Environeering was acquired and in a game of musical chairs became part of organizations with spray tower scrubbers. They used the ‘not invented here” criterion to reject the rod deck scrubber. The group was later acquired by Andritz who invented a rod deck scrubber as an improvement over the spray tower. It is unlikely that any of the original rod deck knowledge was used by Andritz. But maybe it was.

Andritz could have had access to Coal Fired Boiler Decisions. This service was created to make sure knowledge was not lost and that new designs could be properly evaluated. Until recently it was funded through subscriptions by utilities as well as suppliers. However, it is now available free of charge to utilities. This easy access should encourage utilities in India, Vietnam, Malaysia and other countries to make the system the basis of important decisions.

For more information on this service click on 44I Coal Fired Power Plant Decisions

Bob McIlvaine can answer your questions at 847 784 0013, rThis email address is being protected from spambots. You need JavaScript enabled to view it.