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The results of studies on the effect of phosphorus-containing waste on hydrobiont organisms are presented. When studying the effects of phosphorus-containing waste (sludge and slag) on hydrobionts, different systematic categories of hydrobionts were used as test objects: species of diatoms: Sinedra ulna, Navicula gracilis, Amphora ovalis, Pinnularia viridis, unicellular green algae: Scenedesmus guadricauda; Scenedesmus protuberans, Chlorococcum sp., Chlorella vulgaris, Cyanobacteria Oscillatoria limosa, protozoa: Amoeba proteus, Amoeba limax, Euglypha acanthophora, Paramecium sp., Vorticella convallaria,, invertebrates: Colpoda steinii, Rotatoria, Calldina, Aeolosoma, Nematoda. The results of biotesting samples of phosphorus-containing waste showed that the toxic effect on planktonic and benthic organisms depends on the quantitative and qualitative parameters of phosphorus-containing waste. It was found that the 1,0±0,1% concentration of phosphorus-containing slags and slurries turned out to be non-toxic, a further increase in the concentration of waste to 10,0±0,9% has an acutely toxic effect. At the same time, phosphorus-containing sludge turned out to be more toxic than slag. Indicator species were identified: Synedra ulna, Amphora ovalis, Rotatoria, Calldina, which are eliminated from the composition of hydrobiocenosis. [ABSTRACT FROM AUTHOR]

A complex of investigations was performed to study the technological capabilities for application of combined gas-slag protection in MIG-process of copper alloy deposition on steel. It is shown that at semi-submerged arc surfacing (by semi-open arc) it is possible to control the technological characteristics of the welding arc, namely: increase its spatial stability, improve the pattern of electrode metal transfer (essentially reducing its spattering fraction), as well as ensure high-quality protection of the deposits from oxidation. Application of such a combined protection is particularly rational at highly efficient process of two-electrode MIG surfacing. [ABSTRACT FROM AUTHOR]

In the work, the influence of different amounts of boron microadditives on the structure and operational properties of metal of the type of tool steel 25Kh5FMS, produced by arc welding using the experimental flux-cored wires, was experimentally determined. Microalloying additives were introduced directly into the charge of experimental flux-cored wires during their manufacture. It was found that microalloying of the deposited metal of the type of steel 25Kh5FMS with boron in the amount of 0.007...0.04 % does not deteriorate the quality of deposited beads formation and separation of the slag crust. At the same time, when the boron content in the deposited metal is ≥ 0.02%, the formation of a large number of crystallization cracks is observed, which has an extremely negative effect on its operational properties. Moreover, it was experimentally found that the introduction of boron microadditives in the amount of 0.007...0.01% to the deposited metal of the type 25Kh5FMS leads to an increase in its heat resistance and wear resistance at elevated temperatures by 1.2...2.0 times. With an optimal content of microalloying additives, a refinement of the structure of the deposited metal, some increase in microhardness and, probably, the formation of complex spherical carboborides in the alloy matrix occur. In view of the obtained data, it is recommended to use boron in the deposited metal of the type of tool steel 25Kh5FMS in the amount of 0.007...0.01% in order to improve its operational properties. 12 Ref., 4 Tabl., 11 Fig. [ABSTRACT FROM AUTHOR]

Background. An increase in the recovery of copper during the processing of converter slags to concentrate is achieved by depleting them in the reduction processes in the converter before being transferred to the enrichment plant. Purpose: to study the interaction of the ingredients of the reducing agent contained in the industrial waste of metallurgy with the components of the converter slag to develop an effective technology for its depletion. Methodology. The objects of research are a charge from clinker and converter slag of JSC AGMK. Old, accumulated and new converter slags were analyzed. Visual control of the presence of clinker was also used. Originality. Based on the results of the study, it was found that in the process of converting copper mattes in the first period, the depletion of converter slags occurs as a result of the reduction of magnetite to wustite in its composition with the components of the reducing agent contained in the industrial waste of non-ferrous metallurgy. Findings. It is proposed to deplete the converter slags in the converter, in the first period. At the same time, the extraction of copper into blister copper is equal to 95%, while at the concentrator its through extraction is equal to 50%. It is possible to increase the end-to-end copper recovery up to 75%. [ABSTRACT FROM AUTHOR]

Background. One of the ways to intensify copper production is to involve industrial wastes, including copper slag, in the processing. To extract copper from it, reducing agents are introduced into the heated liquid slag of the furnace, as a result, copper passes into the matte phase. Purpose. It is reasonable, from a thermodynamic point of view, to propose for the role of a reducing agent in liquid copper furnace slag carbon components that are part of used car tires with slag components, Methodology. The probability of carbothermal reactions was estimated by determining the change in thermodynamic functions, taking into account the temperature dependence of the isobaric-isothermal potential. The kinetic equations were derived from the dependence of the equilibrium constants of the reactions on the Gibbs energy. in Microsoft Excel. built Ellingham diagrams to determine the optimal process temperatures. Originality The mechanism, kinetics and thermodynamics of the processes of interaction of liquid copper slag with carbon in the composition of car tire waste were studied, and a general Ellingham diagram of the process was constructed. Findings. It has been established that in slag the reactions of reduction of oxides (CuO, Cu2O, Fe2O3, Fe3O4, FeO) with carbon are endothermic. The decrease in temperature in the system of liquid slag with the carbon component of tires is justified. The limiting stage of the process is the wustite reduction reaction. It goes in the kinetic mode, other reactions - in the diffusion mode. The optimum process temperature depends on the wustite reduction reaction: 1150°C is the optimum process temperature in general. [ABSTRACT FROM AUTHOR]

Background. In connection with the increase in the production of cements, the search for raw materials of technogenic origin, the development of highly reactive compositions of raw mixtures is relevant. Purpose: to develop of compositions of low-carbonate and high-reactive compositions of raw mixtures and low-temperature technology of SAG clinkers and cements based on them. Methodology. The calculation of the compositions of raw mixtures was carried out according to an independently developed methodology. Standard equipment was used for firing, allowing for clinker firing and cement testing. The reactivity of raw mixtures was studied using a complex of physicochemical methods. Originality. The sequence of the formation of minerals in the process of firing SAG raw mixtures has been established. It has been shown that in the process of low-temperature firing of the SLA of raw mixtures, including screening of limestone, phosphogypsum and copper slags of flotation concentration, minerals stably coexist in the temperature range of 1150-1200 ° C. Findings. The compositions of low-basic raw mixtures were calculated. The sequence of formation of sulfominerals and the temperature range of stable existence during firing with different values of modular characteristics were determined, the physicochemical parameters of cements based on SAG clinkers were determined. [ABSTRACT FROM AUTHOR]

Background. At present, the urgent problem facing the mining and metallurgical industry of Uzbekistan is increasing the complexity of the use of raw materials, extracting valuable components from man-made waste, involving them in processing. Technogenic raw materials of ferrous metallurgy in the form of steelmaking slag are subjected to enrichment, but the concentrate obtained in this case has a too small fraction, which cannot be loaded into the metallurgical furnace due to large losses by the gas flow. To avoid dust carry-over, the technogenic raw material of fine fraction after its enrichment can be processed into a valuable product, iron ore coal metallized pellets used in the form of raw materials in steel smelting. Purpose. Processing of man-made waste in the form of furnace steel-making slag, with the receipt of iron ore coal metallized pellets, which can be used as raw materials for steel melting. Methodology. To determine the degree of enrichment of furnace slags by the jigging method, experiments were carried out in a laboratory two-chamber diaphragm jigging machine MOD-2. And also was studied the washability of furnace slag on one level concentration table of the LKS -1Ya grade. The effectiveness of the reducing ability of coke and Angren coal for iron oxides was carried out in a laboratory furnace. Originality. The optimal indicator of the size of steel-making slags for the extraction of iron and its compounds from ferrous metallurgy slags by the method of gravity concentration has been determined. The physicochemical processes occurring during the heat treatment of ore-fuel pellets in a reducing environment have been determined. Findings. As a result of research and development, a method has been developed for processing steel-making slag, which makes it possible to obtain an additional amount of raw materials for steel smelting, as well as the use of production residues in the construction industry. [ABSTRACT FROM AUTHOR]