Assessment of three spectroscopic techniques for rapid estimation of calcite in copper ore
Revista : IEEE Transactions on Instrumentation and MeasurementVolumen : 59
Número : 7
Páginas : 1911 - 1917
Tipo de publicación : ISI
Abstract
This paper presents the assessment of three spectroscopic techniques, i.e., Raman Spectroscopy (RS), ultraviolet fluorescence (UVF) spectroscopy, and energy-dispersive X-ray diffraction (ED-XRD), for measuring calcite concentration in copper ore. The results for the three methods are compared in terms of their correlation coefficient and prediction error (root-mean-square error of prediction, RMSEP).
These approaches substantially shorten the measurement time with respect to current laboratory procedures from 300 min down to 1, 15, and 9 min for RS, ED-XRD, and UVF, respectively, while preserving a good accuracy level (RMSEP} < 0.577). Prediction models were calibrated and validated for the three techniques, using the correlation coefficients R^2 and R^2, the error of prediction (RMSEP), and the error of calibration (root-mean-square error of calibration, RMSEC). R^2 values of 0.90, 0.88, and 0.94 were obtained for the RS, UVF, and ED-XRD models, respectively. The calibration and validation were performed for calcite concentrations ranging from 2.9% to 10.7%, and although the ED-XRD model performed slightly better than its RS counterpart, the time taken by the latter is significantly shorter than that by the other two, representing a good candidate for online estimation of calcite concentration.