Stabilization methods for the treatment of weathered arsenopyrite mine wastes: Arsenic immobilization under selective leaching conditions

被引:24
作者
Alvarez-Ayuso, E. [1 ]
Murciego, A. [2 ]
机构
[1] IRNASA CSIC, Dept Environm Geochem, C Cordel de Merinas 40-52, Salamanca 37008, Spain
[2] Salamanca Univ, Dept Geol, Plza Caidos S-N, Salamanca 37008, Spain
关键词
Mine wastes; Arsenic; Stabilization; Calcite; Ferric sulfate; Aluminum salt slags; SEQUENTIAL EXTRACTION PROCEDURE; AMORPHOUS FERRIC ARSENATE; IRON-OXIDE; CRYSTALLINE SCORODITE; PHASE-TRANSFORMATIONS; CONTAMINATED SOILS; SURFACE-CHEMISTRY; AQUEOUS-SOLUTION; MOBILITY; FERRIHYDRITE;
D O I
10.1016/j.jclepro.2020.125265
中图分类号
X [环境科学、安全科学];
学科分类号
08 ; 0830 ;
摘要
The release of arsenic from weathered arsenopyrite mine wastes represents a grave environmental issue, especially when dealing with former mining areas. The evaluation and development of measures to manage this type of wastes in a sustainable and economic way are required. In this study different methods based on the application of chemical amendments were assessed as stabilization systems. For this purpose, weathered arsenopyrite mine wastes with the occurrence of amorphous ferric arsenates (AFA)/scorodite as main secondary products, as determined by X-ray diffraction (XRD) and polarizing microscopy, were used. Stabilization studies were performed employing two different amendments applied at diverse doses, namely a combination of calcite and ferric sulfate (CC + Fe(III) salt) and a by-product generated from the processing of aluminum salt slags (BP-AlOx). The efficacy of such treatments was assessed using both batch and column leaching essays. Under the equilibrium conditions imposed by the applied standard batch leaching tests, both of the treatments at their optimal conditions attained important reductions in the leachable As concentrations (95-98% and 52-79%, respectively), making mine wastes acceptable at controlled landfills as established by international legislation. Nevertheless, under flow leaching conditions the treatment employing CC + Fe(III) salt was shown not to be an appropriate long-term stabilization method. Conversely, the treatment with BP-AlOx proved to be more perdurable, decreasing considerably the As release (>50%) under prolonged leaching conditions. This stabilization system allowed simultaneously an important transformation of AFA to scorodite. Additionally, it partially neutralized the acidity generated from mine wastes without exceeding the pH values above which the solubilization of scorodite could be enhanced importantly. (C) 2020 Elsevier Ltd. All rights reserved.
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页数:18
相关论文
共 83 条
[1]  
Alloway B.J., 1995, J COLLOID INTERF SCI
[2]  
[Anonymous], 1978, 600278054 US EPA
[3]  
[Anonymous], EN124574
[4]  
Arribas A, 1979, CHRONIQUE RECHERCHE, V450, P42
[5]   Arsenic release from arsenopyrite weathering: Insights from sequential extraction and microscopic studies [J].
Basu, Ankan ;
Schreiber, Madeline E. .
JOURNAL OF HAZARDOUS MATERIALS, 2013, 262 :896-904
[6]   The incongruent dissolution of scorodite - Solubility, kinetics and mechanism [J].
Bluteau, Marie-Claude ;
Demopoulos, George P. .
HYDROMETALLURGY, 2007, 87 (3-4) :163-177
[7]   Structural characterization of poorly-crystalline scorodite, iron(III)-arsenate co-precipitates and uranium mill neutralized raffinate solids using X-ray absorption fine structure spectroscopy [J].
Chen, N. ;
Jiang, D. T. ;
Cutler, J. ;
Kotzer, T. ;
Jia, Y. F. ;
Demopoulos, G. P. ;
Rowson, J. W. .
GEOCHIMICA ET COSMOCHIMICA ACTA, 2009, 73 (11) :3260-3276
[8]   Arsenopyrite oxidation - A review [J].
Corkhill, C. L. ;
Vaughan, D. J. .
APPLIED GEOCHEMISTRY, 2009, 24 (12) :2342-2361
[9]   Environmental arsenopyrite stability and dissolution: theory, experiment, and field observations [J].
Craw, D ;
Falconer, D ;
Youngson, JH .
CHEMICAL GEOLOGY, 2003, 199 (1-2) :71-82
[10]   Iron amendments to reduce bioaccessible arsenic [J].
Cutler, William G. ;
El-Kadi, Aly ;
Hue, Nguyen V. ;
Peard, John ;
Scheckel, Kirk ;
Ray, Chittaranjan .
JOURNAL OF HAZARDOUS MATERIALS, 2014, 279 :554-561