Apatite-nepheline Ores Research Articles

О влиянии «гидрофобности» газовой фазы на образование флотокомплексов в процессах флотации

Introduction. A model of a three-phase system in which, as a result of hetero coagulation from a bulk liquid, its thin layer has formed, the surfaces of which separate the gas and condensed phases with different potentials, is a wetting film. The study of wetting films adds to the knowledge of the nature of the structure-induced surface forces acting in them, which serves to develop the theory of hetero coagulation and is of interest for solving various topical problems of the theory and practice of flotation. The purpose of the work is to study the influence of “hydrophobic” properties of the gas phase on the separation of minerals by flotation with a vapor-air mixture in flotation schemes with jet countercurrent flow of feed and rough concentrate. Materials and Methods. Methods and installations have been developed to investigate the temperature dependence of the equilibrium thickness of wetting films and wetting edge angles. Studies of wetting films are supplemented by measurements of induction time at adhesion of minerals to each other and to an air bubble on a specially designed installation. In-situ flotation experiments were performed on a sample of apatite-nepheline ores. Results. The temperature dependence of the equilibrium thickness of the wetting film has been revealed, which does not contradict the experimentally established decrease of the exponentially decreasing (non-oscillating) part of the cleavage pressure with increasing temperature. It is shown that the temperature dependence of the boundary angles formed by the wetting film on the hydrophobic and hydrophilic surface is multidirectional. The connection between the temperature dependence of the boundary angle and the temperature dependence of the spreading coefficient obtained from Young’s law and determined by multiplication of parameters characterizing the magnitude and long-range action of forces caused by the difference between the structure and properties of the liquid in the boundary layers and their values in the volume is shown. “Hydrophobicity” of the bubble is associated with a smaller range effect of structural repulsion forces compared to hydrophobic attraction forces. By measuring the induction time, it is shown that the “hydrophobicity” of air manifests itself in the difference in the stability of wetting (when hydrophobic and hydrophilic particles adhere to the air bubble) and symmetric (when particles of the same hydrophobicity/hydrophilicity adhere to each other) films as the temperature increases. Discussion. In the framework of the phonon mechanism of surface forces, the dynamic structure of the liquid in the boundary layers (the sign and magnitude of the phonon component of the bowing pressure) determines the selectivity of aggregation and completeness of particle extraction, as well as the stability of symmetric and wetting films from temperature. Conclusion. When discussing the stability of disperse systems, the concepts of additional (to dispersive (van der Waals) and ionic-electrostatic interactions) forces associated with the overlap of boundary layers of liquids with structure parameters changed compared to their bulk values are fruitfully used. Such differences are understood as static deviations of the structure and properties of the liquid induced by the surface. However, the main reason for changes in the stability of wetting films at increasing temperature may be the high sensitivity to temperature of the entire set of rotational and vibrational motions of atoms and molecules of the liquid, i. e., its dynamic structure and the associated phonon component of the wedging pressure. Resume. The results of the study can be used to improve the technological performance of ores enriched by flotation. Consideration of the influence of linear tension on the system with the line of threephase contact will be useful for revealing the peculiarities of flotation of micro-dispersions of minerals by the developed technology.

Development MPC for the Grinding Process in SAG Mills Using DEM Investigations on Liner Wear.

The rapidly developing mining industry poses the urgent problem of increasing the energy efficiency of the operation of basic equipment, such as semi-autogenous grinding (SAG) mills. For this purpose, a large number of studies have been carried out on the establishment of optimal operating parameters of the mill, the development of the design of lifters, the rational selection of their materials, etc. However, the dependence of operating parameters on the properties of the ore, the design of the linings and the wear of lifters has not been sufficiently studied. This work analyzes the process of grinding rock in SAG mill and the wear of lifters. The discrete element method (DEM) was used to simulate the grinding of apatite-nepheline ore in a mill using different types of linings and determining the process parameters. It was found that the liners operating in cascade mode were subjected to impact-abrasive wear, while the liners with the cascade mode of operation were subjected predominantly to abrasive wear. At the same time, the results showed an average 40-50% reduction in linear wear. On the basis of modelling results, the service life of lifters was calculated. It is concluded that the Archard model makes it possible to reproduce with sufficient accuracy the wear processes occurring in the mills, taking into account the physical and mechanical properties of the specified materials. The control system design for the grinding process for SAG mills with the use of modern variable frequency drives (VFD) was developed. With the use of the proposed approach, the model predictive control (MPC) was developed to provide recommendations for controlling the optimum speed of the mill drum rotation.

Разработка методов повышения стабильности эксплуатации подземных сооружений

The existing systems for monitoring the technical condition of mines and other underground structures are increasingly failing to meet modern requirements in terms of accuracy and reliability. This is largely related to a lack of innovative design and construction methods, as well as supporting measures that involve real-time monitoring of the various elements of geotechnical systems in the process of their interaction. These tasks can be solved using the methods of system analysis. The application of modern techniques requires a deep analysis of the object under study. Therefore, the development of a unified method for identifying the input, output, and resultant factors determining the operational stability of mines and underground structures appears to be an important task. In this work, we aim to identify a set of input, internal, and output factors affecting mining deposit structures and their operational parameters. This set is used as the basis for developing a conceptual model for simulating the technical condition of an apatite-nepheline ore mine at different stages of its operation. The scientific significance of the work consists in the development of methods for the analysis of the apatitenepheline deposit and the development of a methodology for constructing a mathematical model based on the method of expert assessments. The practical significance of the work consists in the application of a more accurate model for assessing the technical condition of underground structures, which will lead to an increase in the reliability and efficiency of operation of underground structures.

Study of the composition of an apatite concentrate obtained from apatite-nepheline ores from Khibiny fracture zones

Study of the composition of an apatite concentrate obtained from apatite-nepheline ores from Khibiny fracture zones

Влияние минерального состава апатит-нефелиновых руд на ионный состав флотационной пульпы и технологические показатели флотации апатита

The results of flotation of apatite-nepheline ore are presented, the influence of the mineral composition of apatite-nepheline ores on the ionic composition of flotation pulp and technological parameters of apatite flotation is studied. The depressing effect of Fe(OH)3 and Al(OH)3 for apatite flotation.

Оценка потенциала восстановления экологического состояния природных экосистем, нарушенных при освоении георесурсов, по спутниковым данным

The factors of environmental state restoration of the natural ecosystems disturbed as the result of mining mineral deposits were investigated using the case study of the phytocenosis formed on the enclosing dam of the apatite-nepheline ore processing waste storage in the Khibiny group of deposits according to the technology developed in the Mining Institute of the Kola Scientific Center of the Russian Academy of Sciences for the restoration of disturbed lands through creation of a biologically active environment without deposition of a fertile layer. Based on the data of satellite observations of the monitoring sites during the vegetation period, the impact of relief as well as the heat and moisture availability on the state of the emerging vegetation cover was studied using gradient transects of different exposures along the height of the enclosing dam slope. The spatial resolution of the satellite images was harmonized using the enhanced pan-sharpening procedure with the minimum characteristic size of the dam slope elements and the representativeness of the data obtained when assessing the vegetation cover condition using the vegetation index and the moisture stress index was ensured. Generalization was made of the relationship between the parameters characterizing the vegetation cover state and abiotic factors of its formation using a neural network model. Two artificial neural networks were trained to predict the vegetation and the plant moisture stress indices using the data set obtained from processing of visible, infrared and thermal spectral channels of satellite images of the monitoring sites. The neural network model shows that the vegetation index of the emerging vegetation cover is antibate to the plant moisture stress index - the dominant factor in restoration of the environmental state of the investigated site, and to the surface temperature of the enclosing dam of the tailing dump. Dependence of the predicted moisture stress of the phytocenosis formed ontop the enclosing dam slope on the elevation and exposure was used to assess the potential of its restoration to the forest succession stage corresponding to the phytocenosis of the surrounding natural environment. Zoning of the tailing dump according to the potential for restoration of the environmental state was performed in order to support the decision-making process when planning environmental protection measures.

Microwave-Assisted Synthesis of Titanosilicates Using a Precursor Produced from Titanium Ore Concentrate

Titanosilicates comprise a broad class of materials with promising technological applications. The typical obstacle that restricts their industrial applicability is the high manufacturing cost due to the use of specific organotitanium precursors. We herein report a new approach to the synthesis of titanosilicates using an inexpensive inorganic precursor, ammonium titanyl sulfate (ATS or STA), (NH4)2TiO(SO4)2∙H2O. The latter is an intermediate in the processing of titanium-bearing concentrates produced from apatite-nepheline ores. In this paper, the new synthetic approach is exemplified by the microwave-assisted synthesis of IONSIVE-911, one of the most effective Cs-ion scavengers. The method can be modified to synthesize various titanosilicate compounds.

METHOD OF PREDICTING SEASONAL VARIATIONS IN WATER INFLOW TO UNDERGROUND MINE WORKINGS USING THE WATER CATCHMENT MODEL WITH CONCENTRATED PARAMETERS

The authors suggest using the water catchment model with concentrated parameters for prediction of seasonal variation in water inflow to mines. The efficiency of the slope runoff model application was previously shown on the base of three test subjects operating apatite-nepheline ore deposits in the Khibiny massif. The article provides a simple methodology for water inflow prediction which doesn’t require any specific software. The example is provided of using this methodology for monthly water inflow prediction based on an underground mine in Kuzbass.

Rare Earth Element Resource Potential of Super-Large Deposits in Eastern Fennoscandia

This work has been carried out to assess the rare-earth potential of the main ore minerals of the Lovozero and Khibiny deposits. The loparite and eudialyte deposits are associated with the giant Lovozero intrusion (Eastern Fennoscandia, Kola Peninsula). There are several deposits of apatite–nepheline ores in the Khibiny complex. All these ores take the leading position in the structure of the raw material base of Russia. The highest contents of the sum of rare earth metals (REMs) are typical of loparite ores (the content of ΣREE in loparites is about 28 wt %), light rare earths sharply dominate over heavy ones (the Ce/Yb ratio is about 78000). The sum of REEs in eudialytes is about 2 wt %. A remarkable feature of eudialyte ores is the high concentration of the heavy REM group (the Ce/Yb ratio is about 14). The apatites of the Khibiny deposits occupy an intermediate position: the Ce/Yb ratio is 680, and the average concentration of the REE sum is 0.9 wt %. The conditions of formation of apatite, loparite, and eudialyte ores are considered.

Study of Air Polluted by Microparticles in the City of Apatity, Murmansk Region

Surface layers of apatite-nepheline ores mill tailings were analyzed. During the snowless period in2022, the dynamics of PM2.5 and PM10 dust concentrations in the atmosphere air of Apatity, Murmansk Region, was studied. Excess of MAC of sparingly solubles were detected. Mineralogical analysis of tailings and dust samples were carried out, the presence of nepheline and sodalite was detected, which confirms the involvement of tailing dumps of apatite-nepheline processing plants in air pollution. It was concluded that, in addition to the tailing dump, transport and other industrial sites have a significant impact on the atmosphere air, since airborne dust samples contain small particles of oxidized iron, plastic, glass, and metal scale. The role of green areas in buffer zones and within the boundaries of urban development was emphasized.

Rockburst hazard potential assessment of rocks of the Khibiny massif deposits according to the Kaiser criterion

The mining and geological conditions in the mines worsen due to changes in the stress-strain state of rock masses and their structural disturbance when mining goes to great depths. Under such conditions, it is necessary to assess the impact hazard of ores and rocks that make up the mined deposits. For the prompt implementation of such an assessment, it is proposed to use the Kaiser criterion consisting in the analysis of experimental data obtained on rock samples. The paper presents the results of laboratory testing of rock samples from the deposits of the Khibiny massif under uniaxial compression and tension. The values of their brittleness coefficients have been determined. The possibility of using the Kaiser criterion for a preliminary assessment of rock burst hazard potential has been shown. It has been established that spotty-trachytoid melteigite and trachytoid ijolite-melteigite have a high potential for impact hazard, while spotted apatite-nepheline ore does not have such a potential. A comparison has been made of the obtained results of rockburst hazard assessment of hard rocks from the Khibiny massif deposits according to the Kaiser criterion, as well as the criterion of the Mining Institute of the KSC RAS and the criterion of A. N. Stavrogin. It can be noted that the Kaiser criterion makes it quite easy to carry out a preliminary assessment of rock burst hazard based on the results of testing samples on standard presses. However, to increase the degree of reliability of the data obtained, they must be certified according to the criterion of the Mining Institute of the KSC RAS or the criterion of A. N. Stavrogin.

The use of coevolutionary algorithms for optimizing the operating regimes of the roasting conveyor machine

In modern conditions of constant growth in prices for fuel and energy resources, the problem of increasing the energy and resource efficiency of technological processes of industrial enterprises has acquired particular relevance. It is especially acute for energy-intensive industries, which include high-temperature processing of mining and chemical raw materials. To reduce the energy intensity of complex chemical-technological processes, it is proposed to use the possibilities of computer simulation, for example, to optimize the operating regimes of existing equipment. The article has considered the scientific and practical problem of optimizing the charge heating regimes in various zones of the roasting conveyor machine used to produce phosphorite pellets from apatite-nepheline ore waste stored in dumps of mining and processing plants. The specifics of the optimization task (nonlinearity of the objective function, large dimension of the search space, high computational complexity) are significant limitations for the use of traditional deterministic search methods. It led to the choice of population algorithms, which are based on modeling the collective behavior and are distinguished by the possibility of simultaneous processing of several options. The cuckoo search algorithm, which is distinguished by a small number of “free” parameters that affect the convergence, was used to solve the stated optimization task. To select the optimal values of these parameters, it was proposed to use the idea of coevolution, which consists in the parallel launch of several versions of the selected algorithm with different “settings” for each subpopulation. The management of the chemical-technological system for the processing of apatite-nepheline ore waste, taking into account the basis of the results obtained, will minimize the amount of return and ensure an energy-saving operating regime of the roasting conveyor machine.

Physiological status of reproductive age girls under conditions of technogenic impact in the Kola North

BACKGROUND: An investigation to determine the reproductive health disorders commonly found in adolescent females residing in the North peninsula of Kola, Russia. Insubstantial studies on the physiological status of the reproductive aged females living in a territory that has become highly polluted due to the dust particles of apatite-nepheline ore, determines the relevance of this study and involves the identification of indicators of premorbid state.
 AIM: To examine the physiological status of reproductive aged females living under chronic stress condition caused by exposure to both anthropogenic as well as Arctic environment with an objective to reveal possible pre-nosological deviations as indicators of premorbid state.
 MATERIAL AND METHODS: We conducted an observational, longitudinal analytic "3 waves panel study (2019, 2020, 2021) involving 54 female students 1620 years old from medical college in the city of Apatity, Russia. Physiological status was assessed in accordance with the content of hypothalamic-pituitary-adrenocortical system hormones, metabolites of lipid peroxidation, antioxidant protection, vitamin D, lipids, and carbohydrates using percentile distribution of indicator values. Significance of the differences was determined by comparative analysis of two dependent variables using the Wilcoxon criterion.
 RESULTS: Deviations from the optimal values of physiological state indicators were revealed in more than 25% of the females, which manifested themselves in increased secretion of adrenocorticotropic hormone, cortisol, thyrotropic hormone, and depleting secretion of somatotropic hormone, thyroxine with reduced content of antioxidant protection enzymes. In 95% of females, hypovitaminosis of vitamin D was detected whereas 50% of females were found with diminished values of low-density lipoproteins.
 CONCLUSION: Pre-nosological deviations of the physiological status in the conditions of technogenic pollution testify to the oppression of the bodys protective systems and are predictors of morbidity and are subject to individual correction.

A three-tier system of seismic rock mass monitoring in the Khibiny apatite-nepheline ore deposits

A three-tier system of seismic rock mass monitoring in the Khibiny apatite-nepheline ore deposits

Express Assessment of Apatite Content in Apatite–Nepheline Ores of Ultrabasic Alkaline Complexes Based on Its Luminescent Properties (The First Study Stage)

The article presents the results of the first study stage aimed at analyzing the luminescent properties of the main and minor minerals composing the apatite–nepheline ores and host rocks in the deposits of the Khibiny rock massif (Kola Peninsula, Russia). The main purpose of the work was a search of a stable identification feature providing fast and safe determination of fluorapatite in the mineral mixture of apatite–nepheline ores and solving technological tasks, namely sampling the borehole walls in open pits. The first stage includes studies carried out on pure mono-fractions of four minerals occurring in fluorapatite deposits and possessing obvious luminescent properties: fluorapatite, nepheline, calcite, and sodalite. The authors have revealed luminescence spectra of these minerals and established correlation of their spectral characteristics with the literature data and their consistency. However, the high intensity of sodalite luminescence in a wide band can complicate identification of fluorapatite by the luminescence spectrum in many cases. Therefore, it is reasonable to use the color and intensity of luminescence rather than spectral characteristics.

Using population algorithms to optimize the temperature regime of roasting phosphorite pellets

The problem of rational energy resource use is especially acute for energy- intensive industries, which include high-temperature processing of mining chemical raw materials (for example, the production of phosphorite pellets from apatite-nepheline ore waste by drying and roasting). In this regard, the temperature modes of roasting conveyor machine should ensure not only the completion of the ongoing chemical-technological processes and the required product quality, but also energy and resource saving. Thus, there is an urgent scientific and practical task of optimizing charge heating modes based on the results of modeling heat and mass transfer processes occurring in various zones of the roasting conveyor machine. The impossibility of carrying out expensive full-scale experiments leads to the need to use computer simulation methods. Nonlinearity, large dimension of the search space, high computational complexity make it difficult to use traditional deterministic search methods. Under these conditions, the stochastic methods that deliberately introduce an element of randomness into the search algorithm show good results. Today, population algorithms based on modeling the collective behavior of living organisms and characterized by the ability to simultaneously process several options have become widespread. To solve the optimization problem, it is proposed to use a modified Cuckoo search algorithm (by introducing fuzzy elements), which provides a comprehensive account of a huge number of parameters set for each vacuum chamber of the roasting conveyor machine. The control of the chemical-energy-technological system for the processing of apatite-nepheline ores waste, taking into account the obtained data and based on the existing neural network model of the high-temperature process, will make it possible to minimize the amount of return and provide energy-saving conditions for the operation of roasting units.

The Molecular Weight Distribution of Occluded Hydrocarbon Gases in the Khibiny Nepheline–Syenite Massif (Kola Peninsula, NW Russia) in Relation to the Problem of Their Origin

The origin of hydrogen–hydrocarbon gases present in the rocks of the Khibiny massif in unusually high concentrations has been the subject of many years of discussion. To assess the role of potential mechanisms and relative time of formation of gases occluded in inclusions in minerals, the molecular weight distribution of C1–C5 alkanes in the main rock types of the Khibiny massif was studied. For this purpose, the occluded gases were extracted from rocks by mechanical grinding and their composition was analyzed on a gas chromatograph. It is established that the molecular weight distribution of occluded hydrocarbon gases in the Khibiny massif corresponds to the classical Anderson–Schulz–Flory distribution. In addition, the slopes of the linear relationships are relatively steep. This indicates a predominantly abiogenic origin of the occluded gases of the Khibiny massif. At the same time, a small proportion of biogenic hydrocarbons is present and is associated with the influence of meteoric waters. It was also found that in the Khibiny massif, the proportion of relatively high-temperature gases decreases towards the Main foidolite Ring in the following sequence: foyaite and khibinite–trachytoid khibinite–rischorrite and lyavochorrite–foidolites and apatite–nepheline ores. In the same sequence, an increase in the proportion of heavy hydrocarbons and the increasing role of oxidation and condensation reactions in the transformation of hydrocarbons occurs.

Flotation separation of titanite concentrate from apatite-nepheline-titanite ores of anomalous zones of the Khibiny deposits

Titanium raw materials are widely used for the synthesis of various functional materials – sorbents of radionuclides and rare earth elements, various additives, filler pigments, etc. Since most of titanium concentrates are imported, in line with the import substitution program, production of titanite concentrate from apatite-nepheline ores of the Khibiny deposits is a promising trend for supplying national industry with titanium raw materials. The article presents the results of laboratory studies of flotation separation of titanite concentrate from apatite-nepheline-titanite ores extracted from the upper ore horizon of the Koashvinskoye deposit, where titanite-enriched ores are concentrated. Recovery of titanite concentrate was accomplished using two reagent modes – a mixture of alkyl hydroxamic and carboxylic acids with the addition of distilled tall oil and a mixture of tall oils with the addition of polyalkyl benzene sulfonic acids. The results of the research showed that the first flotation mode, which allows a selective recovery of titanite into the concentrate (titanite content in the concentrate was 93.5 %) is the most efficient. It was shown that flotation separation of titanite concentrate is preferable compared to the chemical method based on sulfuric acid leaching.

Determination of rational steam consumption in steam-air mixture flotation of apatite-nepheline ores

Relevance of the study is determined by the decisions taken to increase the production volume of certain commercial products from mineral raw materials. The scale, impact and consequences of the projects on developing the resource-saving technologies for beneficiation of mineral raw materials are socially significant, and the economic growth of mining production complies with the sustainable development goals. The aim of the study is to develop the flotation circuit and mode that improve the technological performance of beneficiation of apatite-nepheline ores of the Khibiny Massif in the Kola Peninsula. The scientific idea of ​​the work is to develop the flotation circuit, the movement of beneficiation products in which ensures a major increase in the content of the recovered component in the rougher flotation procedure with a simultaneous increase in dressability of the material. The above condition is met when mixing the feedstock with rough concentrate. Recovery of the valuable component from the resulting mixture is accomplished in a mode differing from the known ones in that the heat of steam condensation is used to increase water temperature in the interphase film between the particle and the bubble. For pulp aeration during flotation, a mixture of air and hot steam is used as the gas phase. A high recovery of the valuable component in ore flotation according to the developed circuit and mode is facilitated by increasing water temperature in wetting films due to the steam condensation heat. A high selectivity of flotation with a steam-air mixture can be explained using the concepts of a phonon component of disjoining pressure, the value and sign of which are associated with a difference in the dynamic structure of liquid in the wetting film and bulk liquid.

Естественный радиационный фон в жилых и общественных зданиях в районах проведения горных работ в Арктике

Natural background radiation (NBR) largely contributes to the human inhalation of radionuclides originating from the decay of U-238, U-235 and Th-232 isotopes. This problem is of particular importance for public health in the areas with high seismicity induced by mining operations. The purpose of this article was to assess the impact of mining activities on NBR in the residential and public buildings located in the immediate vicinity of the apatite-nepheline ore mining operations in the Arctic. Materials and methods. The measurements were taken in residential and public buildings of Kirovsk (Murmansk Region) adjacent to open-pit and underground mines. The following were measured: total radioactivity dose of samples of raw ores and their concentrates, their spectral characteristics, as well as the aerosol concentration of radon decay products, and volumetric radon concentration in the basements of residential and public buildings located within 3 km from the mining area. Results. The radioactivity of open-pit ore was significantly (7.3 times) higher than that from underground mines (107,300 ± 9823 and 14,615 ± 1980 Bq/kg, respectively). However, the radioactivity of the final product (apatite concentrate) did not depend on the extraction technique (59,792 ± 865 and 61,827 ± 1022 Bq/kg, respectively). Indoor air concentrations of radon in the basements of buildings located up to 3 km from the mines, increased linearly by an average of 0.15 Bq/m3 for each ton of explosives used in ore breaking. The levels of radon and its decay products in residential and public buildings in areas adjacent to the mining operations did not exceed 100 Bq/m3. Thus, mining and blasting operations in the stress-strain state of ore-bearing rocks might have an important impact on the intensity of radionuclide emissions and changes in NBR inside residential and public buildings located in Arctic settlements adjacent to the areas of apatite-nepheline ore mining.