DIN CEN/TS 15864:2012-11

This document is applicable for determining the leaching behaviour of monolithic wastes under dynamic conditions. This test is performed under experimental conditions relevant to assess the leaching behaviour in view of the considered scenario(s). This test is aimed at determining the release as a function of time of inorganic constituents from a monolithic waste, when it is put into contact with an aqueous solution (leachant). In general, the composition, the temperature and the continuous renewal rate of the leachant are chosen such that the leaching behaviour of the waste material can be studied in view of the considered disposal or recovery scenario. When the release is to be determined without any reference to a specific scenario, the leachant is demineralised water, the temperature and the continuous renewal rate are fixed. This dynamic monolithic leaching test (DMLT) is a parameter for a specific test laid down in EN 12920 and is then not aimed at simulating real situations. The application of this test method alone is not sufficient for the determination of the detailed leaching behaviour of a monolithic waste under specified conditions. In the framework of EN 12920 and in combination with additional chemical information, the test results are used to identify the leaching mechanisms and their relative importance. The intrinsic properties can be used to predict the release of constituents in a given time frame, in order to assess the leaching behaviour of monolithic waste materials, placed in different situations or scenarios (including disposal and utilization scenarios). The test method applies to regularly shaped test portions of monolithic wastes with minimum dimensions of 40 mm in all directions that are assumed to maintain their integrity over a time frame relevant for the considered scenario. The test method applies to test portions for which the geometric surface area can be determined with the help of simple geometric equations. The test method applies to low permeable monolithic materials. This procedure shall not be applied to materials reacting with the leachant, leading, for example, to excessive gas emission or an excessive heat release. This document has been developed to determine the transfer of mainly inorganic constituents from wastes. It does not take into account the particular characteristics of organic constituents nor the consequences of microbiological processes in organic degradable wastes. Procedures to characterize the behaviour of waste materials can generally be divided into three steps, using different tests in relation to the objective. The following test hierarchy is taken from the Landfill Directive on the disposal of waste and the Decision in the Annex II of this Directive on the storage of waste. a) Basic characterization constitutes a full characterization of the waste by gathering all the necessary information for safe management of the waste in the short and long term. Basic characterization may provide information on the waste (type and origin, composition, consistency, leachability, and so on), information for understanding the behaviour of waste in the considered management scenario, comparison of waste properties against limit values, and detection of key variables (critical parameters, such as liquid/solid (L/S) ratios, leachant composition, factors controlling leachability such as pH, redox potential, complexing capacity and physical parameters) for compliance testing and options for simplification of compliance testing. Characterization may deliver ratios between test results from basic characterization and results from simplified test procedures as well as information on a suitable frequency for compliance testing. In addition to the leaching behaviour, the composition of the waste shall be known or determined by testing. The tests used for basic characterization need always to include those to be used for compliance testing. b) Compliance testing is used to demonstrate that the sample of today fits the population of samples tested before by basic characterization and through that, is used to carry out compliance with regulatory limit values. The compliance test should therefore always be part of the basic characterization program. The compliance test focuses on key variables and leaching behaviour identified by basic characterization tests. Parts of basic characterization tests can also be used for compliance purposes. c) On-site verification tests are used as a rapid check to confirm that the waste is the same as that which has been subjected to characterization or compliance tests. On-site verification tests are not necessarily leaching tests. The test procedure described in this document falls in category 1: basic characterization tests. The Committee responsible for this standard is NA 119-01-02-05 UA "Eluierungsverfahren" ("Leaching test procedures") at DIN.