Verfahren zur Herstellung eines künstlichen Betonzuschlagstoffs aus Verbrennungsasche und Vorrichtung zur Herstellung desselben

摘要

Production of artificial gravel comprises: (a) heating combustion ash and fly ash to 120-250 deg C; (b) mixing to form a desired mixture of dried combustion ash, dried fly ash and MgO so that the MgO content of the molten slag (6) is 5-20%; (c) producing coke powder from pulverised coal (23) and heating the materials (7) produced by the slag, and degassing so that a part is reduced by the coke powder produced; (d) melting Fe<(II)> oxide in the preheated materials to form molten pig iron (5) and dissolving chemical elements, produced by reducing other heavy metal compounds and reducing oxides, in the molten pig iron (5) to produce a molten slag (6) containing hardly any heavy metal compounds and gases; (e) forming a slag layer in a cashing mould (3a) and cashing the slag; (f) breaking the cast slag (6s) removed from the mould to a size of 4-40 (preferably 5-25) mm; and (g) recrystallising the broken cast slag by rolling in a heat treatment furnace (4A) at 850-1200 deg C. An apparatus for carrying out the process is also claimed.