Paper Title:
Respirometry Studies of the Bioleaching of a Copper Ore in a Large Isothermal Column
  Abstract

During large-scale column tests at BHP Billiton’s Johannesburg Technology Centre (JTC) during 2005/6 on a low-grade copper ore, the concentrations of both oxygen and CO2 were continuously monitored in feed and exit gas as well as at various intermediate positions over the height of the column. This paper describes results from a test run at 40 °C fed with an air stream enriched to between 1000 and 2000 ppm CO2. Oxygen consumption very closely tracks iron and copper leaching. CO2 is consumed rapidly from the bottom up, resulting in significant depletion midway through the column, even though an enriched feed was used. Oxidation rates decline in CO2 depleted zones, but were not observed to cease completely. This rate of decline is postulated to be linked to a slowly decaying population unable to regenerate itself. Comparison between O2 and CO2 consumption rates shows a linear correlation beyond a minimum oxidation rate. This minimum rate corresponds to a non-growth maintenance energy requirement, and the slope of the linear correlation to the growth yield. Both are functions of available CO2 in the range 50 to 1000 ppm, with maintenance declining and yield increasing. The findings of this study imply that CO2 supplementation in bioheaps will stimulate microbial growth and CO2 consumption, but not necessarily increase the rate of oxygen uptake and hence leaching. Absence of CO2 is expected to result in gradual population decline, but a degree of oxidation continues on the basis of maintenance. In tall heaps CO2 depletion with height is likely and may therefore result in impaired leaching in the upper zones.

  Info
Periodical
Advanced Materials Research (Volumes 71-73)
Edited by
Edgardo R. Donati, Marisa R. Viera, Eduardo L. Tavani, María A. Giaveno, Teresa L. Lavalle, Patricia A. Chiacchiarini
Pages
405-408
DOI
10.4028/www.scientific.net/AMR.71-73.405
Citation
J. Petersen, S. H. Minnaar, C. A. du Plessis, "Respirometry Studies of the Bioleaching of a Copper Ore in a Large Isothermal Column", Advanced Materials Research, Vols. 71-73, pp. 405-408, 2009
Online since
May 2009
Export
Price
$32.00
Share

In order to see related information, you need to Login.

In order to see related information, you need to Login.

Authors: Jaeock Yoon
Abstract:In small buildings and residences in Korea, unvented or improperly vented combustion appliances are used to heat rooms. These heaters are...
583
Authors: Jae Hee Jung, Jung Bum Choo, Sang Soo Kim
Abstract:In diesel engine, generally, the removal of carbon nanoparticles has been based on a filtration system or oxidation reactor with O2 at high...
201
Authors: Kuo Sheng Kao, Wei Che Shih, Da Long Cheng, Po Hsiang Kuo, Pei Shan Hung, Chih Yuan Chan, Chin Ming Wang, Po Tsung Hsieh
Abstract:An expeditious evaluation for photocatalyst is set up (or established) in this study. The optical transmittance of the methyl blue solution...
2050
Authors: Xiao Dong Zhang, Cheng Duan Wang, Jun Jie Jin, Yun Zhong Li
Chapter 3: Environmental Science, Analysis and Engineering
Abstract:In this paper the change of CO2 concentration in an office of a university is continuously monitored, using test multifunction...
993
Authors: Pek Ling Ong, Norlia Baharun, Suhaina Ismail
Abstract:Refractory gold ore understudied showed traces amount of gold from X-ray fluorescence analysis. Phases identified are quartz, muscovite and...
236