Fabrication of Porous Plate with Bimodal Pore Size Distribution Using Molten Slag from Incinerator

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.