Mixed magnesian binders using local silicate waste production

Today, the waste of the mining industry is more than 8 billion tons. Analysis of the literature data showed that most of the man-made waste that is generated as a result of the development of mineral deposits is suitable for use in many industries, in particular, in the production of building materials. The use of technogenic raw materials allows us to solve the following tasks: Environmental aspect - reducing the number of dumps and reducing their volumes. And this, in turn, improves the ecology of regions and territories. 2. Economic aspect - reducing the cost of construction products through the use of almost free raw materials, the release of more competitive products. Of course, it is necessary to provide that part of the costs will be spent on additional processing, revision, activation, modification of this technogenic raw material component. But today we have to think about how to clear the territory of substandard “waste rock” and use it to reduce the production and consumption of natural raw materials. A similar process can create waste-free production.

Remote sensing of the Earth as a part of research of assessing the volume of technogenic raw and the environmental situation during the exploitation of placers

It is known that one of the main nowadays problems of subsoil use is the depletion of reserves. Every year many researchers pay attention on mining waste as a source of replenishment of the resource base. Disputes on the prospects of processing technogenic raw materials are relevant. The object of research is the technogenic neoplasms, which were the result of dredging and hydraulic processing of placer gold. The paper presents the results of assessing the prospects and places of application of information technologies, in particular, the analysis of Earth remote sensing data in the design and organization of work to involve technogenic placers in operation. It is shown that these technologies are able to increase the efficiency of work and reduce labor costs at the stage of preliminary study of potential development targets. Possibilities of detailing the infrastructure facilities of the mining and processing complex are considered. It is proposed to use the vegetation index at a non-traditional time for vegetation research in order to isolate coniferous trees on the formed secondary phytocenoses. An area assessment of the technogenic raw materials of the Kerba gold-placer cluster has been carried out. The analysis of the methodological approach based on remote sensing data is carried out. Aspects of natural vegetation restoration in the post-exploitation period are covered. Optimal combinations of raster data channel combinations for the study of the territory within the boundaries of the object under study are proposed.

On methods of modifying natural minerals

Recently, more and more attention is paid to the ecological safety of the republic due to the increased threat of environmental pollution by radionuclides, particularly by uranium, while the processing of uranium-containing raw materials generates a significant amount of liquid industrial waste. The main waste disposal method is a sorption, which requires the use of inexpensive sorbents. Such sorbents can be obtained on the basis of domestic natural raw materials. The significant disadvantages of natural sorbents are a low sorption capacity, which can be increased by developing effective and relatively cheap methods for their modification. The absence of the methods of modification is a limiting factor for the widespread using of natural sorbents for environmental purposes. Variants of modification of natural aluminosilicate and coal-mineral raw materials of Kazakhstan by physical and chemical methods are considered. The chemical methods include the modification with a mixture of tributylphostat and di-2-ethylhexylphosphoric acid in kerosene to obtain "solid-phase extractants", a mixture of phosphoric acid and polyacrylamide, and the synthesis of organominerals. The possibility of using technogenic raw materials as a modifying reagent has been studied. Zeolite of the previously unexplored Kosmurun deposit and shungite of the Koksu deposit were selected for research, and slags of phosphorus production were selected as a technogenic raw materials. Their physical and chemical properties have been studied.

Processing and production of pellets from poor-grade manganese-containing raw materials

there is a review of current researches in the processing of poor-grade manganese raw materials. The variety of manganese minerals caused by the valent state of metal in compounds is demonstrated. Different processing methods for manganese-containing mineral and technogenic raw materials are considered. The process of extraction of manganese from ferruginous manganese ore using reduction roasting and magnetic separation, beneficiation technology of poor-grade manganese ore to improve the ratio of Mn/Fe; processes of beneficiation and sintering of fine ferruginous manganese ore with low manganese content; production of agglomerate from the concentrate of manganese poor-grade ore to produce ferrosilicon manganese are described. Results of the authors researches intended to obtain concentrate from manganese-containing sludge and to produce hardened pellets suitable for melting into ferromanganese on its basis using a new component of the binder are presented.

The Kinetic Aspects of the Dissolution of Slightly Soluble Lanthanoid Carbonates

The problem of the complex use of mineral raw materials is significant in the context of many industries. In the rare earth industry, in the context of limited traditional domestic reserves and dependence on imports of lanthanides, an unambiguous and comprehensive solution has not yet been developed. Promising areas include the involvement of technogenic raw materials in the industrial turnover. The present study examines the kinetics of the dissolution process of poorly soluble lanthanide compounds when changing the parameters of the system. The results obtained reflect the dependence of the degree of extraction of lanthanide on the following variable parameters of the system: temperature, concentration of the complexing agent, and intensity of mixing. On the basis of the experiment, the values of the activation energy and the reaction orders were calculated. The activation energy of the carbonate dissolution process, in kJ/mol, was as follows: 61.6 for cerium, 39.9 for neodymium, 45.4 for ytterbium. The apparent reaction orders of the carbonates are equal to one. The prospect of using the research results lies in the potential to create a mathematical model of the process of extracting a rare earth metal by the carbonate alkaline method.

Complex Processing of Adsorbent Used in the Purification of Hydrogen-Containing Gas

The problems of processing spent adsorbents with a high concentration of chemisorbed chlorine-containing compounds for their reuse are studied in this article. The genesis of the phase composition and morphology at all technological stages of thermochemical regeneration of the spent adsorbent - Axstrap-860 by means of alkaline modification with a combined solution of sodium and potassium hydroxides has been tested by diffractometry and elemental analysis. The results show that the formation of a layer with an increased concentration of alkali metals in the form of the corresponding carbonates and NaOH on the surface of the granules and in the volume of sodium and potassium aluminates provides adsorption of HCl, which are slightly inferior to the fresh adsorbent. The conditions for the removal of halogen-containing substances from technogenic raw materials with the subsequent isolation of useful products have been optimized: (1) crystalline NaCl intended for the preparation of electrolyte for electrode boilers and steam generators; (2) a mixture of chlorides and hydroxochlorides of aluminum tested in the process of coagulation purification of turbid natural and waste waters; (3) pseudoboehmite for the production of an adsorbent-desiccant and the synthesis of magnesium-aluminum spinel using the technology of destruction-epitaxial transformation, and a promising carrier for catalysts for steam reforming of hydrocarbons. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

ANALYSIS OF THE EFFECT OF METHODS OF INTRODUCTION OF ORGANOMINERAL ADDITIVES INTO MORTARS ON FINE SANDS

the use of technogenic raw materials in the production of building composites is an urgent direction in the technology of production of building materials in view of its economic efficiency, environmental effect and wide possibilities of their application. Recently, the issues of environmental safety in the production of building materials, the possibility of their processing and disposal have come to the fore. All this is dictated by the need for energy and resource conservation, the massive depletion of natural reserves and the progres-sive pollution of the environment due to anthropogenic activities. Construction composites provide ample opportunities for recycling of secondary raw materials, as their structure allows them to be used not only as a filler, but also in some cases as additives for regulating certain properties. More studied and widely used are ash and slag mixtures on the basis of which various organomineral additives are developed. So, on the territory of the Chechen Republic there are dumps of ash and slag mixtures, which, according to their chem-ical and mineralogical composition, are suitable for the design of organomineral additives and fillers in con-struction concretes and solutions. Building solutions are widely used for interior and exterior finishing works during the construction of construction projects in the Chechen Republic, which is characterized by high humidity in the winter, which provokes deformations of the plaster layer on facades. In this article, the de-velopment of an organomineral additive based on an ash-slag mixture is considered to improve the quality of mortar mixtures resistant to such conditions.