The comparison of 7.5 and 15% hydrogen peroxide as oxidizing agent in static tests of acid mine drainage potential in Indonesia

Abstract

Static tests of acid mine drainage potential are an important part of mining water management. Net acid generation (NAG) test is widely used in Indonesian coal mines because of its convenience. This test uses H2O2 to oxidize sulfide minerals within rock samples to determine their net acid-forming capacity. This study aimed to determine the difference between H2O2 at concentrations of 7.5% (the standard in several Indonesian coal mines) and 15% (the standard of the Acid Rock Drainage Test Handbook and Indonesian National Standard) in categorizing rocks as potentially acid-forming and non-acid-forming and in terms of NAG solution characteristics. A total of 564 rock samples collected from two Indonesian coal mining sites were analyzed using pH, NAG, total sulfur, and acid-base-accounting tests. The results of the study showed that there was no significant difference in rock classification or the behavior of contaminants in the NAG solution between 7.5% and 15% H2O2. The characteristics of sulfide minerals in Indonesian coal mines were the main factors influencing the results of the NAG test and behavior of contaminants in the NAG solution. Therefore, H2O2 at a concentration of 7.5% can be used in Indonesian coal mines with relatively low total sulfur concentrations (<5%) and minerals in framboidal form.

Keywords

• Acid mine drainage
• Static test
• Net acid generation test
• Hydrogen peroxide