| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve uniaxial squeezing strength and to lower specific gravity by substantially having components produced by the firing of a fly ash, containing a specific composition of Fe and C, forming substantially from an outer layer and inner layer, forming Fe in the outer layer from hematite and forming Fe in the inner layer from wustite and/or magnetite. SOLUTION: An artificial aggregate contains silicon oxide, alumina, iron oxide, slaked lime and magnesia as the components produced by the firing of the fly ash. And the artificial aggregate contains 3-5 wt.% Fe and 0.2-0.3 wt.% C. The aggregate is produced as follows. A finder, a composition blending material and a foaming agent are mixed with the fly ash, further coal or coke is added as a reducing agent and the resultant mixture is pulverized to have <=15μm average particle diameter. The pulverized material is molded with the addition of water. The molding is fired at 1000-1200 deg.C firing temp. with a retention time in the temp. range controlled to 2-5 min.</p> |
