“Development of a New Hydrophobic Rock Dust.”

Dear Editor:
In the recent September 2014 Coal Age issue on page 40, you had an article produced by David Berg, marketing manager, Carmeuse North America on “Development of a New Hydrophobic Rock Dust.

In this article Mr. Berg discusses Foam Dust. In this area Mr. Berg discusses that “foam-based rock dust is not the answer to the ‘caking’ dilemma.” He also discusses that “if the rock dust has caked, it will not scour off to catch up and extinguish the leading flame of the explosion.” The same is true for so-called “foam-based” rock dust. Berg has no references to any foam dust scouring or explosion chamber testing on these comments.

Next Berg discusses, “The foam rock dust has shown to dry on the mine surface to a consistency similar to that of sponge made of plaster. Once hardened, the foam rock dust will not scour off. Unfortunately, NIOSH has determined that foam will not provide as effective inerting capability in the event of an explosion as dry rock dust.”

Recently, DSI Underground Systems has worked with NIOSH on the development of DSI DWYI Dust, “an air entrained wet rock dusting application method.” DSI DWYI Dust rock dust technology disperses and scours when dry. DSI Underground Systems completed the NIOSH protocol, which included dispersion testing, and built the 38 Liter Coal Dust Explosion Blast Chamber. In the 38 Liter Coal Dust Explosion Blast Chamber testing reviewed and overseen by the University of Kentucky, DSI DYWI Dust product an “air entrained wet rock dusting composition” when dry inerted coal dust explosions on every coal dust explosion event.

Certainly Berg and the hydrophobic rock dust will be a viewed as a tool in the tool box for underground coal mining operators. Hydrophobic rock dust so far has been applied in a dry fashion, adding to the respirable dust count in the mine atmosphere.

DSI Underground Systems’ DYWI Dust product is also a tool in the tool box which is currently under review by the regulatory authorities at this time. DSI is looking forward to competing against the Hydrophobic Rock Dust technologies offered by the various suppliers of rock dust products, with our lower respirable rock dust application technology DYWI Dust, which has proven to scour and inert coal dust explosions when dry.


Jim Pinkley
President & General Manager
DSI Underground Systems Inc.
E-mail: [email protected]