| 摘要 |
<p>PROBLEM TO BE SOLVED: To readily obtain artificial aggregate that has practical properties despite of the kinds of coal ash by crushing coal ash so that its average particle size may becomes less than a specific value, forming the ash and firing the formed product. SOLUTION: Coal ash is crushed into particles less than 5μm that can be readily attained by using a generally used crushing means and the resultant particles are molded and fired. When necessary, the crushed particles are combined with a melting point-lowering agent with a Blaine's specific surface area of 2,000-7,000 cm<2> /g preferably in an amount of 20-60, more preferably 30-50 pts.wt. based on 100 pts.wt. of the coal ash, molded and fired. The melting point-lowering agent is, for example, an iron sauce for cement as iron ore, blast furnace slag, blast furnace dust, copper slag, igneous rock, cement clay as weathering shale, amorphous glass substance as quartz trachyte, obsidian, volcanic ash or glass waste. As a result, artificial aggregate with an absolutely dried specific gravity of >=2.0 and water absorption of <=3% for 24 hours.</p> |
