Horizontal Air-Blocking Shelf Reduces Dust Leakage from Surface Drill Shroud

Details

• Personal Author:
  Potts, J. Drew ; Reed, William R. ; Potts, J. Drew ; Reed, William R.
• Description:
  Installation of a horizontal air-blocking shelf around the inside perimeter of the surface mining drill deck shroud is proposed to improve dust capture. Without the use of this shelf, a strong Coanda effect airflow pattern results in dust leakage to the environment, especially at the shroud-to-ground interface. Bailing air exits the drill hole and travels along the drill steel to the underside of the table, where it fans out across the bottom of the drill table and continues down the sides of the shroud. This dust-laden bailing air then strikes the ground and fans out under gaps between the shroud and the ground. The proposed shelf prevents dust-laden air from striking the ground by redirecting it toward the center of the enclosure, where it can be captured. Laboratory tests demonstrated that the shelf reduced dust levels outside of the shroud by 81% under operating conditions consisting of a 1.9:1 collector-to-bailing-airflow ratio and a 51-mm (2-in.) gap between the shroud and ground. The shelf was 152-mm (6-in.) wide and was located at a height equal to 2/3 the distance measured from the bottom of the shroud to the bottom of the drill table. The air-blocking shelf was also capable of overcoming the adverse impact of vertical leakage along the shroud seams as long as this leakage was confined to an area below the horizontal plane defined by the shelf location. [Description provided by NIOSH]
• Subjects:
  Dust Engineering Mining Occupational Health Safety
• Keywords:
  Control-technology Dust-control Dust-control-equipment Dusts Engineering-controls Mining-equipment Mining-industry
• Series:
  Mining Publications   ; Mining Publications  
• ISSN:
  1075-8623
• Publisher:
  Society for Mining, Metallurgy, and Exploration, Inc.
• Document Type:
  Text
• Genre:
  Journal Article ; Journal Article
• Place as Subject:
  OSHA Region 3 ; Pennsylvania
• CIO:
  National Institute for Occupational Safety and Health (NIOSH) ; National Institute for Occupational Safety and Health (NIOSH)
• Division:
  PRL - Pittsburgh Research Laboratory ; PRL - Pittsburgh Research Laboratory
• Topic:
  Workplace Safety & Health ; Workplace Safety & Health
• Location:
  North America ; North America
• Pages in Document:
  55-60
• Volume:
  324
• NIOSHTIC Number:
  nn:20034905
• Citation:
  Trans Soc Min Metall Explor 2008 Dec; 324:55-60
• Editor(s):
  Yernberg W ; Yernberg W
• Federal Fiscal Year:
  2009
• Peer Reviewed:
  True
• Source Full Name:
  Transactions of the Society for Mining, Metallurgy, and Exploration
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:2620ccaa19b3f6b63f46c0d5c395afea23f002f0967037367ab7a6724defe85eee5a325ab85cb2bf1ff359dc5edac1efcd59e7ce8a8accecbbb5b2f8e0276cdb
• Download URL:
  https://stacks.cdc.gov/view/cdc/227044/cdc_227044_DS1.pdf
• File Type:
  [PDF - 1.23 MB ]