Release of Heavy Metals from the Pyrite Tailings of Huangjiagou Pyrite Mine: Batch Experiments

Abstract

Abstract:To provide the basic information about the release of heavy metals from the pyrite tailings of Huangjiagou pyrite mine, the pyrite tailings were investigated through a series of batch experiments under different initial pH of extractant, temperature, liquid-solid (LS) ratio, and soaking time conditions. Moreover, calcium carbonate was added in the pyrite tailings to determine the reduction effect on the release of heavy metals. The results show that Fe, Cr, Cu, Mn, Zn, and Ni were the major heavy metals in the pyrite tailings. Low initial pH and high LS ratio significantly promoted Fe, Cu, Mn, Ni, and Zn release, and high temperature significantly promoted Fe, Cu, Mn, and Ni release. Only small amounts of Cr were detected at low LS ratios. With the increase of soaking time, the released amount of Fe, Cu, Mn, Ni, and Zn increased to the maximum value within 48 h, respectively. After adding calcium carbonate, the released amounts of Fe, Cu, and Zn reduced at least 70.80% within 48 h soaking time. The results indicate that summer and the early soaking stage are the main phases for the release of heavy metals from the pyrite tailings. In the pyrite tailings, Cr is difficult to release. Adding calcium carbonate can effectively reduce the release of Fe, Cu, and Zn.

Temperature-driven variation in the removal of heavy metals from contaminated tailings leaching in northern Norway

“…Zn mostly exists in residue state in the tailings (Cheng, Danek et al 2018). The change of temperature affects the elements of different forms of heavy metals, thus leading to the differences of heavy metal leaching activities (Liang, Jiang et al 2010;Fan, Zhou et al 2016).…”

“…Leaching activity varies at this temperature. This may be the result of significant changes in the biochemical processes and physicochemical properties at the threshold temperature of 10 • C. So proper temperature will improve oxidizing activity of sulfur-oxidizing bacteria and promote heavy metals release (Fan, Zhou et al 2016;Li Jyur et al 2003). Therefore, the heavy metals' forms and the solution pH also change considerably at this temperature.…”

“…The leaching rate is considered a useful index for assessing the capability for heavy metal transport at different temperatures (Fan, Zhou et al 2016;Shi HS and Kan LL 1989;Yan Q et al 2008). A lower leaching rate indicates a lower heavy metal transport ability and a higher level of safety for the surrounding environment (Alghanmi S I et al 2015).…”

The effect of temperature on the leaching of Cr, Cu, Fe, Ni and Zn from tailings, Ballangen deposit, Norway

“…The optimum temperature for ferrous iron and sulfide oxidation by T. ferrooxidans is between 28°C and 30°C, and at lower temperatures a decrease in metal extraction will occur [37]. The released amounts of Cu, Fe, Mn, Ni and Zn from the pyrite tailings at Sichuan province, China, at a temperature range of 15-45°C were investigated in a laboratory batch experiment and showed the released amount of each metal had an increasing trend as temperature increases [38]. The release characteristic caused by temperature is related to the solubility product constant K sp , which is positively correlated with temperature [38].…”

The Effect of Temperature and Precipitation on the Leaching of Contaminants From Ballangen Tailings Deposit, Norway

“…The column experiment method is complex and expensive. In recent years, some researchers have indicated that the low-cost and simple batch experiment method can substitute the column experiment method in studying the release of heavy metals from tailings [16]. To investigate the leaching of contaminants from tailings at different precipitation rates and different temperatures, a small-scale laboratory batch leaching experiment was designed and performed on the oxidized tailings.…”