Acidification of lead/zinc mine tailings and its effect on heavy metal mobility

W. S. Shu, Z. H. Ye, C. Y. Lan, Z. Q. Zhang, Ming Hung Wong*

*Corresponding author for this work

Research output: Contribution to journalJournal articlepeer-review

146 Citations (Scopus)


The acid-forming potential of lead/zinc (Pb/Zn) mine tailings at Lechang City of Guangdong Province was studied using both net acid generation (NAG) and acid-base accounting (ABA) methods. The pyritic and total sulfur contents of the tailings were 12.6% and 18.7%, respectively. The mean acid neutralization capacity (ANC) was 63.5 kg H2SO4/t while three oxidized tailings samples had an ANC less than zero. The NAG and net acid production potential (NAPP) values were 220 and 326 kg H2SO4/t, and both the NAG and NAPP results indicated that the tailings had a high acid-forming potential. NAG was more accurate than NAPP in predicting acid-forming potential of the tailings due to uncompleted oxidization of pyritic sulfur. Analysis of samples from two profile tests indicated that acidification mainly occurred at the surface (0-20 cm) and had little effects at deep layer of the tailings. Total concentrations of Pb, Zn, Cu, and Cd were increased greatly with depth at the acidified tailings profile, while heavy metal concentrations at different depths of nonacidified tailings profile were similar. The results indicated that depletion of heavy metals at the acidified surface was due to acidification. The diethylenetetramine pentaacetic acid (DTPA)-extractable Pb, Zn, Cu, and Cd concentrations of acidified tailings surface (0-20 cm) were significantly higher than those of nonacidified tailings, which further revealed that acidification enhanced the mobility of heavy metals in the tailings.

Original languageEnglish
Pages (from-to)389-394
Number of pages6
JournalEnvironment International
Issue number5-6
Publication statusPublished - May 2001

Scopus Subject Areas

  • Environmental Science(all)

User-Defined Keywords

  • Acid-base accounting
  • Acid-forming potential
  • China
  • Heavy metal
  • Mine tailings
  • Net acid generation


Dive into the research topics of 'Acidification of lead/zinc mine tailings and its effect on heavy metal mobility'. Together they form a unique fingerprint.

Cite this