MSWI-bottom-ash (IBA) and C&D-waste (CDW) are notoriously difficult to
classify or separate at grain sizes below 12 mm. The problem is caused by the combined
presence of (-1 mm) fines and moisture, which act together to form agglomerates and foul
screens and other separation equipment. Results are presented of an experimental study into
the separation performance of a new type of classifier, called Advanced Dry Recovery
(ADR), which is designed to deal with fine moist materials. The study focused on IBA and
two types of CDW: crushed concrete and sieve sand. For each of these three materials, the
particle size distribution and moisture content of the fine and coarse ADR products were
analyzed. It was found that more than 80% of the fines of the input materials is recovered
into the fine product. For IBA, the reduction of fines in the coarse product resulted in more
than double of the -8 mm non-ferrous metal recovery at the downstream eddy current
separators. The coarse products from crushed concrete showed sufficiently low levels of
cement fines, wood and foams to consistently satisfy the European norm for secondary
aggregates and avoid problems with caking in storing this material. In a final experiment,
about 23% of sieve sand was reclaimed as reusable aggregate.
Keywords: Bottom ash, Construction and demolition waste, Recycling.
