| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a spherical excellent coal ash sand high in the strength of a granulated particle by filling an inorganic fine particle, which has a specific particle diameter and is a residue after the treatment of an industrial waste or a natural clay, between both particles of a coal ash and cement. SOLUTION: The coal ash sand is constituted of the coal ash, cement and the inorganic fine particle having <=0.5μm average particle diameter. The mixing ratio of the components are respectively 60-90 pts.wt. coal ash, 2-25 pts.wt. cement and 5-35 pts.wt. inorganic fine particle. To produce the coal ash sand, a slurry of the inorganic powder having >=5m<2> /g BET specific surface area is added to the coal ash and cement, mixed and stirred at a high speed to be granulated. The slurry of the inorganic power preferably contains a 0.1-1mm diameter secondary particle. The secondary particle becomes a granulation nucleus to accelerate the granulation. The ratio of the secondary particle is preferably 1-10wt.%.</p> |
