The Models for the Description of Highly Mineralized Brines Behavior in Surface Water Bodies
Lyubimova, Tatyana (1); Lepikhin, Anatoly (2)
1: Institute of Continuous Media Mechanics UB RAS, Russian Federation; 2: Mining Institute UB RAS, Russian Federation
Today one of the world's largest Verkhnekamsk potash and magnesium ore deposits is being actively developed. The main production facilities for the development of this field are located within the Solikamsk-Berezniki industrial hub. Until recently, only PJSC Uralkali was engaged in the development of the field, but at present other large companies are actively involved. As a result, the total production volume can reach over 20 million tons per year. This will inevitably have a significant impact on the environment. Surface water bodies are subject to the greatest load, which is caused by the specifics of the adopted technological process. The task of minimizing the impact of such a large amount of polluted wastewater forms one of the main environmental problems of the Perm region.
This task is strongly complicated by the fact that the behavior of discharged highly mineralized brines differs qualitatively from that of the sewage with neutral buoyancy. Because of that, traditional methods for calculating the dilution processes presented in regulatory documents governing the procedure for the discharge of wastewater to the surface water bodies are incorrect. Our investigations show that the discharge of excess brines without effective initial dilution results in a significant heterogeneity of the pollutant depth-distribution in the Kama reservoir. In some areas of the Kama reservoir, the concentration of pollutants in the bottom area is more than an order of magnitude higher than that in the surface horizons. This creates a real danger not only for habitat of benthic hydrobionts, but also for water supply systems, since the end caps of water intakes are located, as a rule, at a considerable depth.
The hydrological regime of the Kamsky reservoir changes very significantly during the year, particularly, the flow rate defining the intensity of hydrodynamical processes in reservoir could vary in more than 20 times. In these conditions, numerical simulation on modern supercomputers becomes the main tool for solving the considered problem. In the present paper we discuss the validity and efficiency of different models and methods for the description of highly mineralized brines behavior in surface water bodies using the example of the Kamsky reservoir. New, very efficient computational technology, combining the calculations in 1D, 2D and 3D formulations, is suggested. The models are verified using the comparison of calculated mineralization fields with the results of field measurements of distribution of specific electric conductivity of water.