toggle visibility Search & Display Options

Select All    Deselect All
 |   | 
Details
   print
  Record Links
Author (up) Burt, R.A.; Caruccio, F.T. url  openurl
  Title The effect of limestone treatments on the rate of acid generation from pyritic mine gangue Type Journal Article
  Year 1986 Publication Environmental geochemistry and health Abbreviated Journal  
  Volume 8 Issue Pages 8  
  Keywords mine water treatment  
  Abstract Surface water enters the Haile Gold Mine, Lancaster County, South Carolina by means of a small stream and is ponded behind a dam and in an abandoned pit. This water is affected by acidic drainage. In spite of the large exposures of potentially acid producing pyritic rock, the flux of acid to the water is relatively low. Nevertheless, the resulting pH values of the mine water are low (around 3.5) due to negligible buffering capacity. In view of the observed low release of acidity, the potential for acid drainage abatement by limestone ameliorants appears feasible. This study investigated the effects of limestone treatment on acid generation rates of the Haile mine pyritic rocks through a series of leaching experiments. Below a critical alkalinity threshold value, solutions of dissolved limestone were found consistently to accelerate the rate of pyrite oxidation by varying degrees. The oxidation rates were further accelerated by admixing solid limestone with the pyritic rock. However, after a period of about a month, the pyrite oxidation rate of the admixed samples declined to a level lower than that of untreated pyrite. Leachates produced by the pyrite and limestone mixtures contained little if any iron. Further, in the mixtures, an alteration of the pyrite surface was apparent. The observed behaviour of the treated pyrite appears to be related to the immersion of the pyrite grains within a high alkalinity/high pH environment. The high pH increases the rate of oxidation of ferrous iron which results in a higher concentration of ferric iron at the pyrite surface. This, in turn, increases the rate of pyrite oxidation. Above a threshold alkalinity value, the precipitation of hydrous iron oxides at the pyrite surface eventually outpaces acid generation and coats the pyrite surface, retarding the rate of pyrite oxidation.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0269-4042 ISBN Medium  
  Area Expedition Conference  
  Notes Sept; The effect of limestone treatments on the rate of acid generation from pyritic mine gangue; London: Chapman & Hall; file:///C:/Dokumente%20und%20Einstellungen/Stefan/Eigene%20Dateien/Artikel/7021.pdf; Opac Approved no  
  Call Number CBU @ c.wolke @ 7021 Serial 14  
Permanent link to this record
Select All    Deselect All
 |   | 
Details
   print

Save Citations:
Export Records: