PRODUCTION OF DOUBLE-LAYER WATER-PERMEABLE PAVING BLOCK

摘要

PROBLEM TO BE SOLVED: To produce a lightweight double-layer water-permeable paving block having a high added value by effectively utilizing an incineration furnace ash such as a sewage sludge. SOLUTION: A mixed powder F, prepared by adding 6-20 pts.wt. total amount of a mixture E containing a clay and a glass powder and/or water glass to be bonding parts to 100 pts.wt. mixed aggregate D obtained by mixing >=60 pts.wt. porous aggregate A, prepared by granulating an incineration furnace ash and baking the granulated ash and having >=0.6mm grain diameter, <=1.45 average apparent specific gravity and closed cells with <=40 pts.wt. total amount of an aggregate B of a crushed porcelain and/or an aggregate C of a crushed feldspar and capable of forming a bulk layer is filled in a pressing mold to fill a predominant quantity of the volume of the pressing mold. The balance of the volume of the pressing mold is then filled with a mixed powder H, obtained by adding 6-20 pts.wt. total amount of the mixture E containing the clay and the glass powder and/or the water glass to be the bonding parts to 100 pts.wt. mixed aggregate G containing >=80wt.% total amount of the aggregate B of the crushed porcelain and/or the aggregate C of the crushed feldspar and capable of forming a surface layer. The bulk layer and the surface layer are integrally press formed and subsequently baked to produce a double-layer water-permeable paving block.