Research on the Characteristics and Mechanism of the Cumulative Release of Antimony from an Antimony Smelting Slag Stacking Area under Rainfall Leaching.

Bozhi Ren,Andrew S Hursthouse,Yingying Zhou,Renjian Deng

doi:10.1155/2017/7206876

Abstract

We aimed to study the characteristics and the mechanism of the cumulative release of antimony at an antimony smelting slag stacking area in southern China. A series of dynamic and static leaching experiments to simulate the effects of rainfall were carried out. The results showed that the release of antimony from smelting slag increased with a decrease in the solid-liquid ratio, and the maximum accumulated release was found to be 42.13 mg Sb/kg waste and 34.26 mg Sb/kg waste with a solid/liquid ratio of 1 : 20; the maximum amount of antimony was released within 149–420 μm size fraction with 7.09 mg/L of the cumulative leaching. Also, the antimony release was the greatest and most rapid at pH 7.0 with the minimum release found at pH 4.0. With an increase in rainfall duration, the antimony release increased. The influence of variation in rainfall intensity on the release of antimony from smelting slag was small.

Highlights

Antimony (Sb) is a typical toxic and harmful heavy metal element; the United Nations health organization stipulates that the body’s daily intake of antimony in water should be less than 0.86 mg/kg [1, 2]
The maximum release concentration from the slag was at the beginning of the leaching period when the initial solid-liquid ratio was 1 : 10 and with continued immersion reaching a maximum converging with the results for solid-solution ratio of 1 : 5. In all cases, the overall trend that is leaching at the beginning of the test is relatively fast, and the rate gradually decreases with time
Through static and dynamic experiments, the study on the cumulative release characteristics and mechanism of antimony in leaching from ore processing slag can be summarized as follows: (1) The trends of antimony release are affected by soliliquid ratios; the lower solid-liquid ratio is accompanied by higher released concentration with greater leached amount of per mass unit of waste and the proportion of dissolution; the maximum amount of antimony released was from the 149∼420 μm particle size range with 7.09 mg/L cumulative leaching concentration

Summary

Introduction

Antimony (Sb) is a typical toxic and harmful heavy metal element; the United Nations health organization stipulates that the body’s daily intake of antimony in water should be less than 0.86 mg/kg [1, 2]. Recent studies have concentrated on the release of heavy metal elements in soil, sludge, dust, and other solid media and the influence of a range of factors on waste leaching patterns [5, 7,8,9,10,11,12,13,14]. Few reports exist on the release characteristics and cumulative leaching mechanisms of antimony in smelting slag stacking area under sustained rainfall. This study, evaluated a release test on antimony smelting waste slag with simulated rainfall. The sources of release of some hazardous elements such as Sb, As, Pb, and Cr from typical antimony ores were determined. Few studies have assessed the release and cumulative leaching characteristics of antimony from waste in smelting slag stacking area under sustained rainfall. Using simulated rainfall, test experiments on the release of antimony from smelting waste slag were conducted

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Conclusion