| 摘要 |
PROBLEM TO BE SOLVED: To synthesize artificial rock as artificial aggregate for concrete which is made non-pollutant and is closely recrystallized from the molten slag of refuse incineration ashes. SOLUTION: Am Mg compd. is supplied to an incineration furnace in such a manner that the MgO content of the molten slag 4 attains 5 to 20% in a stage after melting the incineration ashes at the time of incinerating refuse, by which the components of the generated incineration ashes are previously adjusted. The Fe oxide in the incineration ashes is reduced by reduction melting of the incineration ashes and molten pig iron 2 is stagnated and simultaneously, the molten slag 4 contg. least possible heavy metals, etc., is formed and is stagnated in the upper part of the molten pig iron 2. The molten slag 4 is allowed to make primary recrystallization in accordance with an eutectic solidification phenomenon in the state of slowly cooling the slag after slag-off independently from the molten pig iron 2. The cast slag 4A subjected to the primary recrystallization is held in a temp. atmosphere of about 1,000 deg.C to cause the secondary recrystallization of the amorphous part remaining in the cast slag 4A, by which the densely recrystallized artificial rock 24 is formed. |
