Re-use of Sieve sand from demolition waste

Abstract Sieve sand originates from activities as sorting and/or breaking of demolition waste. In a breaking process the first step is a sieve step, to remove the fines. Next, the coarse material is broken and upgraded to a secondary raw material, which can be used as a coarse aggregate in concrete, or as a road construction material. The fine material (sieve sand) cannot be applied without due consideration. The sieve sand may be contaminated with Poly cyclic Aromatic Hydrocarbons (PAHs) to such an extent that, according to the Dutch Building Materials Decree, the sieve sand is not applicable as a granular building material. For this reason Van Bentum Recycling Centrale ordered TNO to carry out a research into the possibilities of stabilising/solidifying the sieve sand in such a way that the PAHs are fixed (immobilised). In the Building Materials Decree the organic contaminants are assessed on the basis of total concentration, in mg/kg. However, from an environmental point of view, not the total concentration, but the leaching is relevant. For this reason, the impact on the environment of the application of stabilised sieve sand has been assessed in terms of mg leached per square meter surface area by TNO. The results of the leaching tests performed, show that even highly contaminated sieve sand (containing up to 1,000 mg/kg PAHs) can be sufficiently stabilised. Only 0.7 mg/m 2 (being 0.002 % of the total concentration) is being leached during the 64 days lasting Dutch diffusion test.