Assessment of environmental condition in the waste disposal site of an ex‐alumina plant near Obrovac, Croatia

Abstract

The waste disposal site of the abandoned alumina plant near Obrovac, Croatia, contains two basins filled with red mud and waste base in total amounts estimated at 0.85 × 106 and 0.65 × 106 m3, respectively. The Red mud was analyzed for its major components, heavy metals content, free base content and leaching properties under different conditions of pH and temperature. Concentrations of 15 elements (Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, As, Rb, Sr, Y, Zr, and Pb) were measured using tube excited EDXRF. The major compounds were determined by XRD, and AAS and XRF methods were used for elemental concentration determinations in different types of leachates. It was found that a possible threat to the environment from red mud under normal environmental conditions could be caused only by leaching of alkalis and V. On the other hand, the concentrations of V, Cr, Cu, As and Se in the waste base and the pH are much higher than allowed for technical waste waters discharged directly into the environment. Waste base treatment (neutralization and heavy metal removal) can be achieved in a one‐step process. During this process, neutralization of acidic red mud would result in the production of a gel‐like coagulant. Copyright © 2004 John Wiley & Sons, Ltd.

Dissolution of sodium, aluminum and caustic compounds from bauxite residues

“…In addition to alkaline compounds such as NaOH (Liu et al, 2007), the leaching of heavy metals, such as Cr, Cu, Ni, and Pb, can cause problems (Ghosh et al, 2011;Rubinos and Barral, 2013), although the leachable alkali may be of a greater concern in some cases (Kutle et al, 2004). The removal of (heavy) metals can be carried out by chemical or biological leaching methods (Qu et al, 2013;Vachon et al, 1994).…”

Examination of the influence of treatments and mineral composition on the point of zero charge of red mud

“…Uprkos, različitim mogućnostima primene [2][3][4], masovno korišćenje ovog materijala do danas nije postignuto, pa se on uglavnom odlaže kao jalovina. Neadekvatno odlaganje crvenog mulja može predstavljati potencijalnu opasnost po životnu sredinu i živi svet [5][6][7]. *Autor za korespondenciju: Slavko Smiljanić E-mail: slavkosm@gmail.com Rad primljen: 03.…”

The Zrmanja River Estuary (Adriatic Coast, Croatia) – the Need for Interdisciplinary Approach to Protection of Coastal Areas

“…Although the wider area is poorly populated, the recognized anthropogenic pressures include the decommissioned alumina factory Jadral [24,38,58] and the reversible hydroelectric power plant Velebit [4,24].…”

“…The ex-alumina factory Jadral is situated on the right bank of the river canyon, about 8 km upstream from the mouth of the Zrmanja River into the Novigrad Sea ( Figure 6). Despite the fact that the plant was in operation from 1978 to 1981, due to its unprofitable production and lack of own resources it left behind large amounts of alkaline sludge (650,000 m 3 ) and red mud (850,000 m 3 ) enriched with metals [38]. The remediation of residues and removal of the factory had started in 2006 and during the field study in 2010 it was not yet completed.…”