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Purpose. Solving the problem of increasing the pumping equipment operational lifetime when pumping-out contaminated groundwater in the iron-ore industry by extracting the hard, abrasive part, using magnetic filters based on permanent ferrite magnets. Methods. To produce spherical hard-magnetic ferrite elements that catch finely-dispersed magnetic and weakly-magnetic abrasive particles when pumping-out contaminated groundwater in the iron-ore industry, barium ferrite powder BaО∙6Fe2O3 is applied, which is usually used for obtaining hard-magnetic ferrites. Spherical elements for filling a magnetic filtering installation are obtained by the method of spheroidizing the barium ferrite powder in a dragee machine. Sintering of spherical granules obtained from barium ferrite powder is conducted in a high-temperature atmospheric electric box furnace. The sintered spherical elements made of hard-magnetic barium ferrite are magnetized using a magnetic pulsed toroidal-shaped setup in a pulsed constant magnetic field. Findings. For continuous pumping-out and purification of contaminated groundwater from magnetic, weakly-magnetic and non-magnetic highly abrasive particles with the help of magnetic filters, a scheme of a filtering installation of two sections is pro-posed. A technology for producing spherical permanent magnets from barium ferrite powder has been developed for a filtering installation, which includes a coarse purification column with hollow-spherical permanent magnets of 16-17 mm in diameter and a fine purification column with full-bodied spherical barium ferrite magnets of 6-7 mm in diameter. Originality.The term of pumping equipment operation is doubled if to eliminate abrasive wear due to the filtering two-section installation by filling with barium ferrite spherical magnets. In the case of changing the filter, idle time is reduced by using the supplementary auxiliary column. The possibility of processing filtration products and their use in the field of construction and metallurgy without environmental pollution is substantiated. Practical implications. The scheme of magnetic groundwater purification in the iron-ore industry is proposed, consisting of a filtering column of coarse and fine purification from abrasive particles. A technology for producing spherical magnets with different diameters has been developed to ensure the quality of the process. The research results allow to increase the operational lifetime of pumping equipment by eliminating abrasive wear, which will lead to significant savings in the replacement and repair of centrifugal pumps. Keywords: pumping equipment, groundwater, wear, barium ferrite, spherical magnet, filter, iron-ore industry

The work is devoted to the creation of an energy-saving microwave technology of composite materials for thermal insulation based on an inorganic polymer—liquid glass—and the establishment of the formation patterns of their structure and properties, depending on the parameters of microwave radiation. Due to volumetric heating and the mechanism of "non-thermal" action of microwave radiation on processed objects, the duration of their heating is significantly reduced, and the performance properties of products are improved due to the modification of the structure of the liquid glass matrix under the influence of its irradiation with this type of energy. In the course of the research, the relationship between the processing conditions and the obtained properties of heat-insulating materials was established. The prospects of using the microwave electromagnetic field in the production of new building materials, expanding their range, and improving quality and competitiveness are shown, which is a priority for the modernization and innovative development of the construction industry.

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