Two radiometric methods for the fast determination of calcium in cement raw mix

Abstract

Fast determination of calcium in cement raw mix is a very important problem from the economic point of view. In order to solve this task, the following two methods are proposed: (i) Non-dispersive X-ray fluorescence analysis (using¹⁰⁹Cd as a source of primary radiation); (ii) back-scattering of β-particles (using⁹⁰Sr+⁹⁰Y as a source). The influence of the following factors has been studied in both methods: (i) concentration of iron in the matrix; (ii) water content; (iii) grain size of the sample. The influence of the energy of the primary radiation on the slope of a calibration curve has been analyzed in the fluorescence method. In the concentration range of 42–52% CaO, the absolute standard error is 0.17% CaO in the fluorescence analysis, and 0.5% CaO for the method of back-scattering of β-particles. The average time of a determination is about 2 min.