Application of the Flotation Tailings as an Alternative Material for an Acid Mine Drainage Remediation: A Case Study of the Extremely Acidic Lake Robule (Serbia)

Abstract

Flotation tailings rich in carbonate minerals from the tailings deposit of the copper mine Majdanpek (Serbia) were applied for neutralization of the water taken from the extremely acidic Lake Robule (Bor, Serbia). Tests conducted in Erlenmeyer flasks showed that after neutralization of the lake water to pH 7, over 99% of aluminum (Al), iron (Fe), and copper (Cu) precipitated, as well as 92% of Zn and 98% of Pb. In order to remove residual Mn and Ag, the water was further treated with NaOH. After treatment with NaOH, all concentrations of the metals in the lake water samples were below discharge limits for municipal wastewater according to the national legislation of the Republic of Serbia. The results of this work suggest that mining waste could be used for active neutralization of the acid mine drainage. The use of the mining waste instead of lime could reduce the costs of the active treatment of the acid mine drainage.Metals 2020, 10, 16 2 of 15 conducted by Pavlović et al. [8]. They used a laboratory scale cascade line system with three reactors for selective precipitation of metals such as iron, copper, nickel, and arsenic from the synthetic solution that resembled acidic effluent from the open pit mine from the Bor area. The neutralizing agent was 1 M NaOH. Recently, Masuda et al. [9] applied hydrated lime (Ca(OH) 2 ) for neutralization of acidity and selective precipitation of metals from the water collected from Lake Robule using semi-industrial scale equipment for active AMD treatment with two chemical reactors. Stopic et al.[10] used red mud from Greece and Germany firstly for neutralization of AMD (pH value of 2.3) from South Africa and for precipitation of copper. Mwewa et al. [11] performed precipitation of poly-alumino-ferric sulfate coagulant for wastewater treatment using AMD solution from South Africa.There are active and passive methods in the treatment of AMD [12,13]. The conventional method for active neutralization of the acid mine drainage is the application of Ca(OH) 2 . This process is fast and efficient; hydrated lime increases the pH of the solution, resulting in precipitation of the dissolved metals in the form of metal hydroxides [14]. The main disadvantage of this technology is generation of the voluminous sludge. The price of the lime and need for the dehydration, solidification, and stabilization of the sludge after treatment increase the capital and operational costs of the AMD neutralization process [14][15][16]. More recently, passive methods have been attracting more attention due to reduced energy and maintenance costs [13]. With a view toward sustainable development, many studies have focused on finding alternative materials for AMD neutralization. Kaur et al. [17] investigated the application of the waste material from the alumina refining industry (Bayer liquor and precipitates formed by sea water neutralization of the Bayer liquor) to treat AMD from mine pit water. Kefeni et al. [18] reviewed technologies for AMD treatment, including alternative approaches for AMD neutra...

Submarine Tailings in Chile—A Review

“…Very high concentrations of heavy metals (Cu, Co, Pb, Cd, Ni) were detected in mollusks. The definitive cessation of the tailings discharge is unknown since its environmental authorities have not carried out a serious study on the ecosystem [32,33].…”

Increases in pH of acid mine drainage with coal fly-ash application

“…AMD is formed when tailings containing sulfide compounds are lifted to the surface and then exposed to oxygen [1,2]. This AMD generally has a very low pH [3,4] and high heavy metal concentrations [5,6], so it will be a serious environmental problem when AMD flows into public waters. The presence of AMD in open water systems lead to serious problem to benthic invertebrates [7] and fish community [8,9].…”

Development of an analytical model for copper heap leaching from secondary sulfides in chloride media in an industrial environment

“…This resource has begun to be exploited in recent decades in Chilean mining [28], mainly due to the situation of water scarcity in the country. It is worth highlighting the rise in copper leaching in chloride media, finding applications, as stated in the literature, from processing of secondary copper sulfide minerals [22,23,29,30], to copper smelting slag leaching [31,32]. On the other hand, though leaching of primary copper sulfides, such as chalcopyrite [33,34], is also possible, it is economically infeasible at industrial scale.…”