Porous plate with bimodal size distribution was prepared using the molten slag from
the incinerator. The slag was pulverized to 1-10μm using a planetary ball mill. On heating the
pellet formed with this powder, its relative density at 750°C and 800°C were 70% and 85%,
respectively. At 750°C, each particle partially attached together at the contacted point. At
800°C, however, all particles melted, coagulated together and increased their size. The slag
powder was granulated using a tumbling granulator, resulting granules of 0.5-5mm size. The
compressive strength of the granule sintered at 750°C was 0.39 kgf. The density of the granule
decreased by ~60%. The sintered granules were mixed with a proper amount of glass powder
and starch water, and the slurry was cast to a mold (φ80mmx10mm). After drying the cast plate,
it was heated at 630°C. The density of the plate was 1.2 gcm-3, ~43% of original slag value. The
sound absorption coefficients of the plate were 0.02 and 0.4 at 200Hz and 1500Hz, respectively.
MLEP-Fail calibration for 1/8 inch thick cast plate of 17-4 steel.