Ore Passes
Hello Phil,
Maybe this is better late then never.
Mud Rush was often mentioned in DO's in South Africa but none of the designers were unfortunate enough to see one first hand. Free moisture is mainly provided by the drill coolants and there is little that can be done about that. Reef (rock) was gathered in a slusher gulley, which says it all. The ore was then scraped over the top gape of the ore pass and the rock & water went into free fall until they reached rock bottom. I suppose the same process prevails today.
In the mid 1980's I obtained a copy of the National Coal Board (UK) standard for STAPLE SHAFT BUNKERS & I was pleasantly surprised by the detailed information therein. I have not kept my copy but it might be possible to chase one down from the bunker lining people eg Kalenborn or Greenbank.
What it boils down to is that if you want to eliminate Mud Rush then you have to spend the money to screen the fines & drain off the water. These are simple geometric design matters which require more financial commitment than engineering knowledge. That is not a new scenario for a Mine house, is it?
Water is clearly the culprit here. The particle distribution could be maintained in a reasonably dry feed, but if free water is available then the slush will get rinsed down to the shaft outlet. Oil drillers use wedge wire screens to protect borehole pumps & a similar set up might work in an ore pass, if installed in an upstream chamber.
Regards - John Gateley ■
John Gateley johngateley@hotmail.com www.the-credible-bulk.com
Re:
Phil,
Dr. Graham Mustoe at Colorado School of Mines has done a number of analysis on ore passes using DEM. He might be able to give you some inside into some of the things involved with Ore passes.
www.mines.edu is the web page for Colorado School of Mines and you can find contact info for him there.
Best of luck,
Grzegorz "Greg" Dewicki
Overland Conveyor Co., Inc.
www.overlandconveyor.com ■
Untitled
Posted on November 01, 1999 at 21:53:57:
I am trying to find information on the phenomena known as a ‘Mud Rush’. This occurs in the ore passes of underground mines where the material in the ore pass suddenly changes from a sold mass to a virtual liquid. When the ore pass is opened the material flows out engulfing the people and equipment in the exit area.
I am researching this as I believe that the Particle Size Distribution and moisture levels play a significant role and urgently need to find a method of preventing any re- occurrence
Thank You
Phil Lovering ■