Wilde PGM de ,
Beek AIM van de ,
Keijzer J ,
Aalbers TG
154 p
in Dutch
1990
Toon Nederlands
English Abstract The joint research project "Environmental implications
of useful applications of primary and secondary materials to be used on or
in the ground", was carried out by four institutes i.e. RIVM, ECN, TNO and
INTRON. In this research project an estimation had been made of the
environmental implications when primary materials (natural materials) are
replaced by secondary materials (waste materials) in road constructions and
building materials. For this estimation the standard leaching test was
used. The standard leaching test is applicable to materials with particles
smaller than 3 mm. Therefore, some materials have to be reduced by crushing
and grinding. This report concerns the determination of the size
distribution of the raw materials and materials after grinding by dry
sieving and wet sieving. On the basis of the results of the test sieving an
estimation of the surface area's was made. In general, it was found that
the particles smaller than 20 mum contributes more than 90% to the total
surface area and less than 10% to the mass weight of the materials.
Grinding hardly affects the percentage of mass weight of the fractions > 20
mum and < 20 mum. A relatively small increase of the fraction < 20 mum
results in a considerable increase of the total surface area. The surface
area of waste incinerator slag had been measured by the BET-method too. It
was found that it wasn't expedient to determine accurately the surface area
of particles larger than 1 mm. Moreover, the relation between the particle
size of the material and the leaching behaviour of Cd, Cr, Cu, Mo, Ni, Pb,
and Zn had been investigated by the column-tests on waste incinerator slag,
which had been grinded to different particle sizes. No significant
relationship was found between the leaching behaviour and the particle
size.