Numerical Simulation of Highly Saline Wastewater Discharge into Water Objects to Improve Discharge Devices

Abstract

The expansion of large-tonnage chemical production (primarily, of mineral fertilizers) calls for the development of new methods for discharging excess brines into surface water objects. This task is complicated by the fact that, due to the suppression of vertical turbulent pulsations, “heavy” brines may spread over considerable distances in the near-bottom region without any significant decrease in their concentration. Some suggestions for optimizing exhaust structures designed to discharge wastewater containing heavy impurities are proposed based on numerical modeling. The calculations based on solving the three-dimensional problem with different wastewater discharge conditions have shown the structures providing location of exhaust devices near the reservoir surface to be the most efficient ones. However, such structures are difficult to implement in a certain reservoir section. In this case, an easy-to-implement and quite efficient configuration is that including bottom arrangement of exhaust devices and selective intake of highly saline wastewater from sludge storage facilities. Irrespective of the chosen scheme for disposal of highly mineralized wastewater, their discharge must be carried out in strict coordination with the hydrological regime of water intake. This approach will provide the most efficient use of the assimilative capacity of water body and the best way to reduce the ecological impact on both the water body and the environment.