scholarly journals Scientific substantiation and practical realization of selective comminution process of polymetallic mineral raw materials

2020 ◽  
Vol 192 ◽  
pp. 02003
Author(s):  
Holger Lieberwirth ◽  
Oleg Popov ◽  
Tatiana Aleksandrova ◽  
Nadezhda Nikolaeva

The results of various methods of studying structural and texture characteristics, physical and mechanical properties determining the liberation of ore minerals are presented in the article. They allow to estimate the content of ore minerals in them, to analyze particle size distribution and spatial distribution of their grains, etc. These data provide more detailed information on the strength properties of ore and the possibility of selective comminution at the stage of study and design of beneficiation schemes. The analysis of mineralogical and geochemical composition as well as the results of technological research have shown that investigated copper-nickel ores satisfy the criteria of selective comminution.

2020 ◽  
Vol 992 ◽  
pp. 253-258
Author(s):  
M.P. Lebedev ◽  
V.N. Tagrov ◽  
E.S. Lukin

The article deals with the manufacture of modern structural ceramic materials from clay and loam deposits of the Republic of Sakha (Yakutia). The importance and relevance of the development of the production of building materials from local raw materials is emphasized, since this will certainly affect the effectiveness of the construction complex as a whole. The successful development of the construction complex is capable of not only stimulating growth in all sectors of the economy, but also contributes to solving the most pressing social problems. Today, Yakutia has huge reserves of mineral raw materials for the production of a wide range of building materials and products. Of practical interest are wall materials made from clay soils. Given the features of the region’s raw material base, this work focuses on additional processing of traditional material. Controlling the complex physicochemical and structural-mechanical transformations that occur during heat treatment, a methodology has been developed for creating a composite material that will allow competitive innovative materials with enhanced strength properties to be produced with a reinforcing element with a glassy phase matrix of mullite crystals. The fabricated samples have a wide range of physical and mechanical properties and allow using it as a high-quality structural building ceramics, as well as industrial floor technical tile.


2020 ◽  
Vol 2020 (3) ◽  
pp. 24-31
Author(s):  
Z Galimova ◽  
◽  
H Babakhanova ◽  
M Abdunazarov ◽  
I Ismoilov ◽  
...  

Both raw and recycled fiber materials are used for paper production. The increase in percentage use of the latter is due to their paper-forming properties, availability and low cost. The article explores the possibility of using pulp from the inner layer of mulberry twig bark. Mulberry twigs, after removing leaves, which are the main raw material in silk production, have no practical industrial application. Recycling waste - mulberry branches - for the production of pulp is therefore relevant as it is aimed at solving raw material and environmental problems. The purpose of this work is to use local raw materials for paper production, study the impact of processing method of the grinding process on paper forming properties. During grinding the mechanical processes of changes of fibers determine mainly structure of a paper sheet, and colloidal-physical processes - bind and ability of fibers to form strong, homogenous and smooth structure of paper. The structure of the sheet of paper facilitates excessive or "selective" ink absorption into the pores of the paper and thus predetermines the quality of reproduction during the printing process. Methods for determining the physical and mechanical properties of papers were used in this work, and changes in the surface structure of samples cast at various technological modes of the milling process were studied. The results of the study revealed that the addition of cellulose mass from the inner layer of mulberry twig bark helps to obtain a strong paper. The optical properties of the paper, which contains cotton and cellulose from the inner layer of mulberry branch bark, are explained by the whiteness of the added fibers themselves. The strength properties of the paper at a weight grinding degree of 300 CWR are explained by the bond between the split and strongly interwoven fibers of the cellulose fibers. It has been established that the addition of more than 30% cellulose from the inner layer of the mulberry branch bark to the paper pulp mass is undesirable, as this adversely affects the whiteness of the paper


2018 ◽  
Vol 56 ◽  
pp. 03001 ◽  
Author(s):  
Tatyana Aleksandrova ◽  
N. Nikolaeva ◽  
Holger Lieberwirth ◽  
Alexander Aleksandrov

Investigations on the possibility of selective grinding and benefication of quartz-pecoraite ores of the Ufaleiskoye deposit have been carried out. Methods of computer X-ray microtomography have been used to study the morphometric features and pore volume parameters of samples, and these data was compared with results of quantitative microstructural analysis. The performed research shows the powerful capabilities of X-ray computer microtomography method for solving scientific and practical problems related to the study of physical and mechanical properties of rocks, the determination of ore minerals liberation, the evaluation of their content, the analysis of the granulometric composition and the spatial distribution of their grains. Analysis of mineralogical and geochemical composition of ores showed that these ores meet the criteria for selective disintegration. An analysis of flotation experiments results showed that when material is grinded in a roll mill, the consumption of reagents is 25% lower than when grinding in a ball mill if the same degree of nickel extraction is achieved.


2018 ◽  
Vol 8 (1) ◽  
pp. 132-138
Author(s):  
Виктор Бурындин ◽  
Viktor Buryndin ◽  
Лариса Бельчинская ◽  
Larisa Belchinskaya ◽  
Андрей Савиновских ◽  
...  

The possibility of obtaining wood and plant plastics without a binder (WP-WB) in the presence of a catalyst of man-ganese-containing sodium vanadomolybdophosphate has been investigated. The use of this catalyst makes it possible to reduce the temperature of hot pressing in closed molds from 1,800°C to 1,600°C. The fractional composition of the initial press raw material influences physical and mechanical properties of WP-WB. Higher values of the plastic properties are obtained by using a 0.7 mm fraction, which is associated with an increased specific surface area of the particles compared to 1.3 mm particles. The results has showed that the samples obtained by using the catalyst have increase in strength properties (flexural strength, flexural modulus, hardness) at lower pressing temperature, but reduction of water resistance performance has been observed . This is explained by the increase in the content of functional groups when using a catalyst. The process of obtaining plastic can be broken down into two successive stages: the first is hydrothermal destruction of lignin-carbohydrate complex (initial moisture of the press raw material is 12%, the temperature of hot pressing in closed molds is 160 ... .180 ° C) and partial chemical activation of lignin as a result of hydrogen peroxide and catalyst application; the second stage - formation of plastic with the formation of a network structure due to the formed functional groups. It is established that the values of physical and mechanical properties of WP-WB are higher than those of plastic obtained on the basis of plant raw materials (PP-WB). This can be explained by the fact that lignin of coniferous species has the guaiacylpropane structure, while plant raw material has a hydroxyphenylpropane structure


2018 ◽  
Vol 196 ◽  
pp. 04061 ◽  
Author(s):  
Marina Panfilova ◽  
Nikolay Zubrev ◽  
Olga Novoselova ◽  
Sania Efremova

For the waterproofing of tunnels and the uniform distribution of space between the lining of tunnels and rock, composite injection solutions are used. To improve the physical and mechanical properties of cement composites, the nanoconstruction effect is used, which is possible when using nanoparticles with extended geometry. Nano-additives and nanomodifiers consisting of nanoparticles, both natural and artificial and technogenic, can be used for the production of cement-containing solutions and concretes. For example, under certain conditions nanocrystalline powder of oxides and hydroxides of aluminum to nanotechnogenic raw materials can be referred to wastes of technogenic origin. The paper investigated the effect of nano-additives-boehmite, which is a waste of production, to increase the strength and frost resistance of plugging materials made on the basis of cement when administered. It is established that the use of boehmite as an additive in cements leads to an increase in the strength properties of concrete and increase its frost resistance, which is a prerequisite for long-term and reliable operation of the composite solution. Thus, the composite solution modified by boehmite is the basis for the creation of plugging solutions


Author(s):  
R. M. Vorozhbiyan ◽  
G. N. Shabanova ◽  
A. N. Korogodskaya

The development results are given for the refractory concretes based on the modifed alumina cement with the using of the chemical industry wastes. The quantitative ratio for the near-gravity materials, the technological factors' influence on the concrete strength, the dependence of its strength properties on the flling aggregate's kind and its curing conditions were defned in the article. It was shown that the physical and mechanical properties of the developed concretes are as good as those of the commercial concretes. According to all technical characteristics this kind of production can be introduced for using as the high temperature vessels' lining material.Ill.6. Ref. 11. Tab. 4.


2018 ◽  
Vol 143 ◽  
pp. 02009 ◽  
Author(s):  
Andrey Stolboushkin ◽  
Danil Akst ◽  
Oksana Fomina ◽  
Aleksandr Ivanov

The given paper investigates the influence of manganese-containing wastes on bulk coloring and physical and mechanical properties of wall ceramic materials with matrix structure. Conventional research methods to study physical and mechanical properties of ceramic specimens were used in the present study. The structure and phase state of decorative ceramic materials were investigated by means of physical-chemical analysis. Authors suggested the model to form coloring layer in ceramic matrix composites based on argillaceous raw materials and coloring pigment. Macrostructure was studied on ceramic samples manufactured according to the developed method from clay loam of moderate plasticity and wastes of manganese mining. The paper provides results of pilot testing on production of colored ceramic brick. It was found that incorporation of coloring component does not decrease strength properties of ceramic matrix materials. Authors defined the palette and color code for decorative ceramic specimens manufactured with different content of coloring component of manganese mining wastes according to RGB color codes chart.


Author(s):  
L. F. Sennikova ◽  
G. K. Volkova ◽  
V. M. Tkachenko

The results of studies of the stress-strain state of copper M0b after deformation under different schemes of equal channel angular pressing (ECAP) are presented. The level of macro and micro stresses in copper has been determined in various ECAP modes. It is shown that the strength properties, deformation porosity and parameters of the fine copper structure differ depending on the loading pattern.


Crystals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 360
Author(s):  
Pauls P. Argalis ◽  
Laura Vitola ◽  
Diana Bajare ◽  
Kristine Vegere

A major problem in the field of adsorbents is that binders (kaolin clay, bentonite) introduced to bind zeolites and ensure the needed mechanical strength, are not able to sorb gases like CO2 and N2, and decrease the overall adsorption capacity. To solve this problem, one of the pathways is to introduce a binder able to sorb such gases. Thus, in this study, the physical and mechanical properties of a novel binder based on metakaolin and its composite with zeolite 4A in the granular form were studied. Metakaolin was used as a precursor for alkali-activated binder, which was synthesized using an 8M NaOH activation solution. Raw materials were characterized using granulometry, X-ray diffraction (XRD), and differential thermal analysis (DTA); and final products were characterized using density measurements, a compressive strength test, XRD, Brunauer–Emmett–Teller (BET) analysis, and scanning electron microscopy (SEM). Alkali-activated metakaolin was found to be efficient as a binding material when data for morphological properties were analyzed. A relationship was observed—by increasing the liquid-to-solid ratio (L/S), compressive strength decreased. Zeolite granule attrition was higher than expected: 2.42% and 4.55% for ZG-0.8, 3.64% and 5.76% for ZG-1.0, and 2.73% and 4.85% for ZG-1.2, measured at 4 and 5 atmospheres, respectively.


2021 ◽  
Vol 11 (8) ◽  
pp. 3334
Author(s):  
Jorge Suárez-Macías ◽  
Juan María Terrones-Saeta ◽  
Francisco Javier Iglesias-Godino ◽  
Francisco Antonio Corpas-Iglesias

Energy consumption, because of population development, is progressively increasing. For this reason, new sources of energy are being developed, such as that produced from the combustion of biomass. However, this type of renewable energy has one main disadvantage, the production of waste. Biomass bottom ash is a residue of this industry that currently has not much use. For this reason, this research evaluates its use as a filler in bituminous mixtures, since this sector also has a significant impact on the environment, as it requires large quantities of raw materials. With this objective, first, the physical and chemical properties of biomass bottom ashes were evaluated, verifying their characteristics for their use as filler. Subsequently, bituminous mixtures were conformed with biomass bottom ash as filler, and their physical and mechanical properties were analyzed through particle loss and Marshall tests. The results of these tests were compared with those obtained with the same type of mixture but with conventional and ophite aggregates. This study confirmed that biomass bottom ash was viable for use as a filler, creating mixtures with a higher percentage of bitumen, better mechanical behavior, and similar physical properties. In short, more sustainable material for roads was obtained with waste currently condemned to landfill.


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