The analysis showed that the composition of the original ash sample included mainly quartz, lime, anhydrite, calcite and smaller amounts of orthoclase, periclase, gehlenite, larnite, merwinite, pseudowollastonite, hematite, ettringite, melilite and dolomite (Table 2).
The resonance lines at -71.5 and -107.3 ppm arise from larnite ([Ca.sub.2]Si[O.sub.4]) and quartz, respectively [18].
The XRD results showed that the BOF slag constitute of magnesium ferrite (Mg[Fe.sub.2][O.sub.4]) and
larnite ([Ca.sub.2]Si[O.sub.4]).
The most characteristic minerals are the following: wustite (FeO), which is well crystallized into round and oval-shaped particles, similarly crystallized lamellar larnite with some allite ([C.sub.2]S + [C.sub.3]S), both of which are embedded in a microcrystalline matrix of brownmillerite ([C.sub.4]AF), and mayenite ([C.sub.12][A.sub.14][O.sub.33]).
The following mineralogical components resulted from X-Ray diffraction analysis of slag: wustite FeO; calcium ferrite Ca[Fe.sub.2][O.sub.4]/(CF); srebrodolskite [Ca.sub.2][Fe.sub.2][O.sub.5]/([C.sub.2]F); larnite [Ca.sub.2]Si[O.sub.4]/([C.sub.2]S); alite [Ca.sub.3]Si[O.sub.5]/([C.sub.3]S); mayenite [Ca.sub.12][Al.sub.14][O.sub.33]/[C.sub.12][A.sub.7]; brownmillerite [Ca.sub.2][(Al,Fe).sub.2][O.sub.5]/[C.sub.4]AF.
The content of six main components: lime CaO, anhydrite CaS[O.aub.4], quartz Si[O.sub.2], calcite CaC[O.sub.3], periclase MgO and
larnite [Ca.sub.2]Si[O.sub.4] was determined.
Initial ash contains quantitatively fixable amounts of lime CaO, quartz Si[O.sub.2], anhydrite CaS[O.sub.4], calcite CaC[O.sub.3],
larnite [Ca.sub.2]Si[O.sub.4] (dicalcium silicate 2CaO x Si[O.sub.2]) and periclase MgO.
CaO, MgO, quartz and
larnite ([beta]-[Ca.sub.2]Si[O.sub.4]) were the main phases in the calcinated samples.