Nadezhda Nikolaeva

Dr. Nadezhda Nikolaeva

orcid

Research Focus & Metrics

Academic Career Length

16Years (2011-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
13 August 2020 in Mineral Processing and Extractive Metallurgy Review
Verified
Journal Article
Closed access
TATatiana Aleksandrova
Tatiana Aleksandrova
AEAbdalla Elbendari
Abdalla Elbendari
Nadezhda NikolaevaNadezhda Nikolaeva
Nadezhda Nikolaeva
This work aimed to upgrade a low-grade sedimentary phosphate ore through attrition scrubbing/desliming and an anionic/cationic reverse flotation technique. The mineralogical and chemical examination showed that the sample contained low-grade apatite minerals (P2O5 ~ 22.5%), and the main associated gangue minerals were gypsum and quartz. The effects of both collector and depressant dosage were investigated and optimized in each individual flotation process. The results of attrition scrubbing accompanied by desliming showed that a high content of P2O5 (27.97%) with a recovery of 72.1% was obtained in the coarse size fraction (+53 µm), and the majority of quartz and gypsum separated in the fine size fraction (−53 µm). The effect of using a new tall oil collector mixture was investigated during the anionic reverse flotation. Sodium tripolyphosphate (STPP) was used as a phosphate depressant during anionic and cationic reverse flotation. The flotation results of the deslimed sample demonstrated that cationic reverse flotation was much more desirable in terms of achieving a high grade and recovery of P2O5 compared to anionic reverse flotation. Considering the statistical design, a maximum grade of 31.23% P2O5 with a recovery of 95.22% was obtained in the non-floated fraction using 950.88 g/t of the collector (amine) and 500 g/t of the STPP.

24 March 2021 in ACS Omega
Verified
Journal Article
Open access
Nadezhda NikolaevaNadezhda Nikolaeva
Nadezhda Nikolaeva
TATatiana N. Aleksandrova
Tatiana N. Aleksandrova
ECElena L. Chanturiya
Elena L. Chanturiya
AAAnastasia Afanasova
Anastasia Afanasova
Analysis of the current technical solutions for the processing of iron ores showed that the high-grade ores are directly exposed to metallurgical processing; by comparison, low-grade ores, depending on the mineralogical and material composition, are directed to beneficiation including gravitational, magnetic, and flotation processes or their combination. Obtaining high-quality concentrates with high iron content and low content of impurities from low-grade iron ores requires the maximum possible liberation of valuable minerals and a high accuracy of separating features (difference in density, magnetic susceptibility, wettability, etc.). Mineralogical studies have established that the main iron-bearing mineral is hematite, which contains 69.02 to 70.35% of iron distributed in the ore. Magnetite and hydrogoethite account for 16.71–17.74 and 8.04–10.50% of the component, respectively; the proportion of iron distributed in gangue minerals and finely dispersed iron hydroxides is very insignificant. Iron is mainly present in the trivalent form—Fe2O3 content ranges from 50.69 to 51.88%; bivalent iron is present in small quantities—the FeO content in the samples ranges from 3.53 to 4.16%. The content of magnetic iron is 11.40–12.67%. Based on the obtained results by the investigation of the features of magnetite–hematite ores from the Mikhailovskoye deposit, a technological scheme of magneto-flotation beneficiation was proposed, which allows producing iron concentrates with 69% of iron content and less than 2.7% silicon dioxide for the production of pellets with subsequent metallization.

10 November 2022 in Journal of Mining Institute
Verified
Journal Article
Open access
PDF file
ARArtem Romashev
Artem Romashev
Nadezhda NikolaevaNadezhda Nikolaeva
Nadezhda Nikolaeva
Bulat Lenarovich GatiatullinBulat Lenarovich Gatiatullin
Bulat Lenarovich Gatiatullin
In this paper, an adaptive approach has been developed for automatic initialization of the thickening curve using machine vision technology, which makes it possible to determine with high accuracy the material parameters necessary for the design of thickening and clarification apparatuses. Software has been developed that made it possible to search for the coordinates of the condensation critical point in automatic mode. Studies on two samples of materials (tailings of apatite-containing ores and gold-bearing concentrate) were carried out and made it possible to statistically prove the reproducibility of the results obtained using the parametric criteria of Fisher and Bartlett. It has been established that the deposition curves are approximated with high accuracy by the Weibull model, which, together with the piecewise linear approximation, makes it possible to formalize the method for determining the critical point coordinates. The empirical coefficients of the Weibull model for two samples are found, and the final liquefaction and settling rates of the studied materials are determined.

7 August 2021 in Minerals
Verified
Journal Article
Open access
PDF file
Tatyana AleksandrovaTatyana Aleksandrova
Tatyana Aleksandrova
Nadezhda NikolaevaNadezhda Nikolaeva
Nadezhda Nikolaeva
Anastasiya AfanasovaAnastasiya Afanasova
Anastasiya Afanasova
ARArtem Romashev
Artem Romashev
VKValentin Kuznetsov
Valentin Kuznetsov
Deterioration of mineralogical and physical characteristics of mineral raw materials results in the formation of the primary task for the comminution processes—reduction in the size of ore to obtain a material with a certain granulometric composition, which in turn is achieved by overgrinding of raw materials and, consequently, an increase in energy costs. The work aimed to justify the possibility of selective disintegration of mineral assemblages of polymetallic ores of various genesis at the stage of crushing based on in-depth investigation and revealing of interrelation and mutual influence of mineralogical-geochemical features, textural-structural and technological properties. Structural and textural features have been studied by the methods of computed X-ray microtomography. Experimental and theoretical investigations of mineralogical and technological parameters of raw materials, as well as research on crushing using different types of crushers, made it possible to substantiate the possibility of selective disintegration for polymetallic ores.

1 May 2023 in Energies
Verified
Journal Article
Open access
PDF file
Tatyana AleksandrovaTatyana Aleksandrova
Tatyana Aleksandrova
Nadezhda NikolaevaNadezhda Nikolaeva
Nadezhda Nikolaeva
VKValentin Kuznetsov
Valentin Kuznetsov
In this article, typomorphic associations of microelements in carbonaceous caustobioliths and oils are defined as indicators of naphthogenesis based on the analytical survey of the literature and our own research. Various approaches to the studying of crude oil genesis from the position of abiotic and complex approaches (polygenesis) are considered. Such approaches are relevant to the prospect and development of offshore oil deposits, localized at ultra-deep levels. For deep deposits, the most prominent hypothesis of oil origin is the abiogenious theory. In the foundation of that approach lays the assumption that hydrocarbons are formed mainly due to reactions of the formed mantle gases and the host rock. Key factors for these reactions to proceed are specific conditions concerning temperature, pressure, and specific catalysts. The article presents the results of thermodynamic and quantum-chemical modeling of the possibility of the organic and organometallic compound formation using the software package HSC Chemistry 6.0. Pointed out the possibility of a low molecular weight hydrocarbon formation due to the contact of ascending flows of mantle gases with cooling natural barriers. The primary synthesis proceeds with the interaction of fluid forms of H2, CO2, and H2S. The estimation of the bonding energy depending on the structure of organometallic compounds was performed using the Avogadro software package. The program used the method of bond potential energy minimization to find the most stable structure of molecules. The metals nickel and vanadium, as the main companion metals of oil, are of the most interest from the position of analysis of their form of existence in the possible formation of hydrocarbons. Vanadium’s and nickel’s accumulation in asphaltene fractions of oils, probably, is caused by complex compounds of metalloporphyrin’s formation. In addition, the high sulfur content is probably associated with polymerization of organic molecules due to the formation of di-sulphide bonds. The method of cavitation extraction of organometallic compounds from oil and complex mineral–oil raw materials has been developed for experimental confirmation of microelements the extraction capability from oil raw materials.

5 January 2023 in Minerals
Verified
Journal Article
Open access
PDF file
Tatyana AleksandrovaTatyana Aleksandrova
Tatyana Aleksandrova
Nadezhda NikolaevaNadezhda Nikolaeva
Nadezhda Nikolaeva
Anastasiya AfanasovaAnastasiya Afanasova
Anastasiya Afanasova
ARArtem Romashev
Artem Romashev
VAValeriya Aburova
Valeriya Aburova
EPEvgeniia Prokhorova
Evgeniia Prokhorova
The possibility of extraction of metals from ores of different genesis, containing low-dimensional structures of rare and noble metals, increases their commodity value and, in a deficit for some types of metals, leads to the need to search and develop new nature-like technologies, which can be used to extract from ores of different genesis almost all valuable noble, rare earth and nonferrous metals regardless of their concentration. This article presents the results of studying the processes of comminution and flotation to extract low-dimensional structures of noble and rare metals from carbonaceous ores using low-temperature and energy impacts at successive stages of the ores’ transformation. With the use of modern mineralogical, physical and chemical methods of research of composition, structure and properties of ores, the initial samples, concentrates and tailings after enrichment were studied. During the study, it was established that the difficulty of extraction of strategic metals from carbonaceous hard-enriched ores consists in fine dissemination of valuable components in concentrator minerals, mutual penetration of ore mineralization into each other and into rock-forming minerals, and in proximity of physical, chemical and technological properties of minerals, which complicates selective extraction of valuable components in concentrates. Also, difficulties in enrichment are associated with high flotation activity of waste rock, which significantly reduces the quality of concentrates.