动态浸滤法研究黄铁矿氧化产酸过程中产酸成分(AP)和中和酸成分(NP)的消耗,讨论了有效NP、AP的确定.50周实验结果表明:(1)中和酸成分NP和产酸成分AP消耗速率呈非线性变化.酸性排放(ARD)前,即pH=4前,AP、NP平均消耗速率VAP与VNP基本相同;ARD开始释放后,VAP〉2VNP;(2)排放液pH〈3后,Fe3+参与并加速氧化反应,AP消耗的平均速率及固溶物溶出速率提高4倍以上;(3)抑制ARD释放的有效NP〈50%,控制排放液中性的有效NP〈30%;引起ARD释放的有效AP〉75%,且ARD将持续释放30年以上.
The depletion of Neutralization Potential(NP) and Acid Potential(AP) and the determination of available AP and available NP in pyrite acidification process were studied by using kinetic flood leaching in humidity cell.50 cycles kinetic test for the studied sample shows that:(1)The rate of NP and AP depletion changed nonlinearly.The average rate of NP depletion(VNP) is almost same as the average rate of AP deletion(VAP) before onset of acid rock drainage(drainage pH=4).VAP is more than 2 VNP after onset of acid rock drainage(ARD);(2) Fe3+ speeds the sulphide oxidation and VAP together with the rate of mineral dissolution increased by over 4 times after drainage pH3;(3) The NP availability controlling ARD is less than 50% and NP availability keeping drainage neutral is less than 30%.The AP availability causing ARD is more than 75% and ARD will last more than 30 years.