Ecological Risk Assessment of Jarosite Waste Disposal

Abstract

Abstract. Jarosite waste, originating from zinc extraction industry, is considered hazardous due to the presence and the mobility of toxic metals that it contains. Its worldwide disposal in many tailing damps has become a major ecological concern. Three different methods, namely modified Synthetic Precipitation Leaching Procedure (SPLP), three-stage BCR sequential extraction procedure and Potential Ecological Risk Index (PERI) Method were used to access the ecological risk of jarosite waste disposal in Mitrovica Industrial Park, Kosovo. The combination of these methods can effectively identify the comprehensive and single pollution levels of heavy metals such as Zn, Pb, Cd, Cu, Ni and As present in jarosite waste. Moreover, the great positive relevance between leaching behavior of heavy metals and F1 fraction was supported by principal component analysis (PCA). PERI results indicate that Cd showed a very high risk class to the environment. The ecological risk of heavy metals declines in the following order: Cd>Zn>Cu>Pb>Ni>As.

Metal recovery from jarosite waste – A resin screening study

“…Commonly produced as a by-product of the hydrometallurgical refinement of zinc from sulphide ores, the impurities present in the waste include Cu, Pb, Zn, Mn, Cd, Al, Cr, Ni, and Co. Major quantities of jarosite are generated in China, USA, Canada, Japan, Australia, and across Europe [1], with India producing approximately 142,000 Tonnes per annum of jarosite type slag as solid waste from the lead and zinc smelting industries [2]. The current method of disposal for industrial jarosite is in open tailing dumps, where the waste is subject to atmospheric weathering, leading to the mobilization of dissolved metals in acidic leachates [3]. The environmental impact following the release of such leachates from jarosite waste depositories is comparable to that of acid mine drainage, whereby downstream ecological populations are adversely affected through elevated metal concentrations and reduced pH [4,5].…”

“…Despite causing environmental damage, some of the metal impurities present within the waste have an intrinsic value which may provide an opportunity for recovery [6]. An approximate composition of an industrial jarosite is given in Table 1 [1][2][3][6][7][8], with prices per tonne for each metal taken from the London Metals Exchange (November 2016) [8]. In the most optimistic circumstances the jarosite waste generated per annum could return a resource recovery value of between £28-49 million.…”

Separation of iron(iii), zinc(ii) and lead(ii) from a choline chloride–ethylene glycol deep eutectic solvent by solvent extraction

“…4,5 Furthermore, elements such as lead, copper and zinc are hazardous and it is important to remove them from the waste prior to disposal. 1,2,6 Thus, reprocessing of secondary waste streams avoids the stockpiling of environmentally harmful elements and can cause the recovery of relatively valuable metals.…”

Thermal Processing of Jarosite Leach Residue for a Safe Disposable Slag and Valuable Metals Recovery

“…The iron precipitation is also possible by producing goethite, paragoethite, or hematite; however, the jarosite process is used most commonly worldwide [4]. The chemical formula of jarosite is ZFe 3 (SO 4 ) 2 (OH) 6 , where Z represents either Ag + , H 3 O + , K + , Li + , Na + , NH 4 + , or 1 2 Pb 2+ [5]. On an industrial scale, typical cations used for precipitation are Na + , K + , and NH 4 + .…”

“…On an industrial scale, typical cations used for precipitation are Na + , K + , and NH 4 + . Jarosite leach residues may also contain unrecovered base metals (Zn, Pb, Cu), critical elements (In, Ga, Ge, Sb), precious metals (Ag and Au), and elements of concern (As, Cd, Hg) [2,6,7]. These iron-rich leach residues are not suitable for use because of their classification as hazardous waste due to the heavy metals they contain [8].…”