Enthalpy of formation of ye’elimite and ternesite

Calcium sulfoaluminate clinkers containing ye’elimite (Ca4Al6O12(SO4)) and ternesite (Ca5(SiO4)2SO4) are being widely investigated as components of calcium sulfoaluminate cement clinkers. These may become low energy replacements for Portland cement. Conditional thermodynamic data for ye’elimite and ternesite (enthalpy of formation) have been determined experimentally using a combination of techniques: isothermal conduction calorimetry, X-ray powder diffraction and thermogravimetric analysis. The enthalpies of formation of ye’elimite and ternesite at 25 °C were determined to be − 8523 and − 5993 kJ mol−1, respectively

TECHNOLOGICAL FEATURES OF COMBINED DEVELOPMENT OF UPHORNY DEPOSITS

In this article, in the basis of the analysis of sources, the technological features of openunderground mining of upland deposits are revealed. The main factors influencing the effectiveness of open-underground mining have been determined, which will need to be taken into account when making design decisions to determine the boundaries of open-underground works