EXPERIMENTAL STUDIES OF HYDRODISINTEGRATION OF MARTITE IRON ORE BY ROTATING WATER JETS
Authors:   Kryvyi Rih National University, Tarasyutin Viktor , Kosenko Andrii ,   M.S. Poliakov Institute of Geotechnical Mechanics of the National Academy of Sciences of Ukraine, Khomenko Oleh ,   Dnipro University of Technology, Kononenko Maksym ,   Dnipro University of Technology
Published: February 2024

Purpose. Obtaining the main initial experimental data to establish a set of calculated dependencies for determining the parameters of the process of hydrodisintegration by boreholes of rich martite ore deposits, for further designing an industrial mine site for hydraulic mining by boreholes and a production technological complex for actual mining. Methods. Testing of an experimental hydraulic monitor installation and equipment for the implementation of the technological process of hydrodisintegration of rich martite ores through production wells with a diameter of 105 mm. Refinement of the criterion for the hydrodisintegration of rich martite ores by pressure jets of medium diameter, in the conditions of natural occurrence of the ore deposit. Determination of the influence of the pressure of the working diameter of the jet and the speed of its movement along the exposure of the face on the range and productivity of hydrodisintegration. Determination of the influence of the geological and structural characteristics of the ore deposit on the parameters of the hydrodisintegration process. Establishment of rational regimes for the impact on the ore massif of a rotating jet to obtain a given granulometric composition of the ore mass. Results. Through wells with rotating jets of water, the fundamental possibility of hydrodisintegration of arrays of rich martite ores with an iron content of more than 65%, a porosity of more than 20% and a uniaxial compressive strength of less than 20 MPa has been proved. It has been established that the hydrodisintegration of of rich martite ore massifs begins with the penetration of pressure water into cracks to a depth of 0.10–0.15 m. At the same time, an increase in pressure in the jet nozzle increases the productivity of the hydraulic monitor, and the use of two rotating jet nozzle increases the productivity of the hydraulic monitor by 2.7 times. The process of hydrodisintegration is accompanied by an increase in the mass fraction of iron in the ore from 67.2 to 68.2%, due to the removal of barren particles and sludge from the slurry. Hydrodisintegration provides a high degree of disclosure of ore minerals, 40–60% higher than in the process of mechanical grinding in a grinding mill. Scientific novelty. The dependence of the change in the performance of the hydraulic monitor and the specific water consumption on the water pressure in the jet nozzle has been established. The dependence of the change in the percentage of iron in the disintegration products of martite ore on the class of their size has been obtained. Practical implication. The use of hydrodisintegration by boreholes of deposits of rich martite ore in the course of their underground mining provides an increase (above natural) in the quality of the extracted ore raw materials and and its beneficiation directly at the place of extraction.