Materiały konferencyjne SEP 1992

Szkoła Eksploatacji Podziemnej * 92 367 of e-potential and the composition and diffusion łayer thickness associated whłch in its turn change the ratio of free and bound water in the rock. Thus, with chsinging of pH the amphoteric compounds electric state also changes alongside with the rocks properties. In the process of the rocks electrochemical stabi1ization the regularities have been established for changing the pH, humłdity, density, electrical resistivity, temperatura, granular -metric composition and physico-mechanicał properties. 4. The thermodynamic conditions of minerał forination The raising of temperatura up to łOO-...115 brings about the changing of thermodynamic conditions which influence the minerał format ion. For example in the area near cathode the poor1y so1ubłe calc i um hydrox i de i s formed as port 1andi te minerał. When combined with carbon acid contained within the rock, certain part of the port 1 andi te is transformed into a more stable calcite: Ca (OH) CO'^ CaCo^ + 20H' The equi 1 ibrium of both sides is determined by the eąuilibrium constant: If the activities CaCO^^^^and Ca(0H)2^^jare equal to 1. then both minerals will be stable only in eąuilibrium with the mixture. The thermodynamic calculation established the influence of temperature on the reaction fIow. The dependence of the eąuilibrium coiostant K % n temperature is deseribed by Wang-Hoff eąuation. The results proved that with the temperature growth the constant goes up according to the linear law and the free reaction energy falls down, the eąuilibrium being shifted to the right and the portlandite is substituted by the calcite.