Critical evaluation of quantitative determination of minerals in slags by a new MCQMA and QXRD methods

Abstract

A new modified chemical quantitative mineral analysis (MCQMA) method was developed and used for quantitative calculation of crystalline and amorphous phases in ladle and blast furnace slags and their slag blends with 20-100 wt% of the amorphous phase. MCQMA calculation was created by combination of the original chemical quantitative mineral analysis (CQMA) with bulk chemical analysis (XRF) and QXRD-Rietveld method with an internal standard (QXRD*). These X-ray diffraction data were used for a) identification of crystalline minerals and for the support of calculation of average oxide formula of amorphous phase for MCQMA calculation and b) for independent separated quantitative determination of crystalline (C(12)A(7), C(3)A, C2S, C3S, MgO) and amorphous minerals and their comparison with data calculated by MCQMA. The advantage of the MCQMA consists also in the possibility to test separately the quality of determined phase percentages provided by MCQMA and QXRD* methods using their feedback conversion on recalculated chemical analysis and compared them with bulk chemical analysis. For the tested data, the comparison showed that both methods provided comparable results.