Experimental modeling of convection-diffuse mass transfer in brine of Dombrovskyi quarry (Kalush, Ivano-Frankivsk region)

The article presents the analysis of diffusion-convective mass transfer processes and their parameters, defines hydrogeochemical criteria for evaluation of brine chemical composition formation in Dombrovskyi quarry of Kalush-Golynske deposit. It has been experimentally determined that the temperature gradient (20 °С) significantly affects the rate of mass transfer in the brines. This is probably due to convection-diffuse processes. The dynamics of processes occurring when fresh water enters the brine surface has been experimentally simulated. Analysis of these data from the point of view of formal kinetics for irreversible process allowed estimating the speed of convection-diffusion process. The rate of self-diffusion of water into saturated brine of galite (D=1,21·10-5 cm2/s) and hydrated (in tritium water) ions of Na+Cl- (D=6,62·10-6 cm2/s) were experimentally studied by the isotope method using the tritium label. According to the spatial dynamics of the half (from equilibrium) tritium concentration, the linear rate of self-diffusion of water into brine (6,56 cm/day) and diffusion of hydrated sodium chloride ions into water (1,10 cm/day) are calculated. At the same time, the change rate of position of half (from equilibrium) tritium concentration in the spatial plan is almost the same: (0,22 cm/day) and (0,23 cm/day), respectively. Mathematical models describing the dynamics of these processes have been constructed. The obtained data make it possible to calculate the rates of salts movement from the depth of the Dombrovskyi quarry to its surface. Estimated amount of fresh water (220 thousand tons), capable to indifundate within a year from the surface to a 100-meter depth in the lower layers of Dombrovskyi quarry brines and dissolve the salt-containing rocks in its sides and the bottom.