STUDY OF THE THERMAL TREATMENT METHOD FOR HIGHLY MINERALIZED WASTEWATER FROM INDUSTRIAL PRODUCTION

Abstract

Highly mineralized wastewater from industrial enterprises is one of the main pollutants of the natural environment.This type of liquid waste is contaminated with mineral substances such as salts of calcium, sodium, magnesium, etc.Despite the widespread implementation of recirculating water supply and new low-waste technologies, the volume of contaminated wastewater remains significant. Therefore, the purification of liquid waste from mineral contaminants is a major problem.A method for thermal neutralisation of highly mineralised liquid industrial waste using intermediate solid heat transfer has been proposed, offering promising prospects for application in metallurgy, chemistry, coal mining, energy and other industrial sectors. Laboratory equipment was developed, with an electric heater and an evaporation column containing an inert heat transfer medium in the form of metal balls. This work investigated the hydrodynamic regime of the evaporation apparatus during the disposal of highly mineralized wastewater on an intermediate solid heat carrier.Experiments were conducted on a granular packing with ball diameters of 10 and 15 mm. During the evaporation process, water was fed cyclically at a speed of 2, 2.5, and 3 m/s. As a result, it was found that the hydraulic resistance of the evaporation apparatus depends on the speed of the hot heat carrier and the type of packing (dry or wet).The conducted laboratory studies showed that the cyclical evaporation of highly mineralized wastewater using an intermediate solid heat carrier (metal balls) allows for reduced energy consumption and the effective removal of mineral contaminants from the water. However, the formation of a salt film on the packing elements reduces the porosity of the layer and increases hydraulic resistance. To ensure the efficient operation of the evaporation apparatus, it is necessary to maintain an optimal level of porosity.