Comparison of different batch leaching tests on steelmaking slags.

Steelmaking slags are suitable for application in road construction. However, leaching characterization of recycled materials is required to determine their pollutant potential and their application's consequences in different scenarios. Leaching tests are used to help to quantify toxic inputs due to mobilization of contaminants; to know what proportion of metals present in residues can be removed by natural leaching; to better understand the behavior of a dump of materials when exposed to external influences and how it will affect the environment. The aims of this paper is explained by the increasing employability of different leaching test methods. From the literature, one can identify more than 100 leaching methods to remove soluble components from a solid matrix. Depending upon the soil characteristics and the scenario, different leaching test procedures might be needed. Leaching tests with EAF slags were performed using four distinct batch leaching standards: the American Method 1311-Toxicity Characteristic Leaching Procedure (TCLP), the European EN 12457 Compliance Test for Granular Waste Materials, the Netherlander NEN 7341 Availability Test - Leaching characteristics of solid earthy and stony and the German DIN 38414-4 German standard methods for the examination of water, waste water and sludge. These test methods are intended as rapid means for obtaining an extract of solid waste. To classify the materials according to their environmental effects, the concentration limit values of the metals imposed by Council Decision 2003/33/EC were used as a reference.