Using of aluminium slags and products of their pro‑cessing in metallurgical production

The work contains the results of the analysis of technical literature and author’s research on the use of aluminium slags and products of their processing in metallurgical production. It has been shown that the bulk of reagents derived from secondary aluminum production wastes (APWs) are used with increased sodium and potassium chloride. This creates some inconvenience for out‑of‑furnace steel treatment due to the increased chloride content in the working area. It is proposed for steel processing to use APWs formed during flux‑free melting or dump aluminium slags. This allows to reduce the content of salt fluxes residues to 1.0–1.5 % and to improve working conditions at ladle furnaces when liquefying refining slags.

Environmental management in the hotel and restaurant complex

In the current context, significant changes are taking place in the structure of Ukrainian industry. Powerful productions of some spheres of activity lose their urgency and, on the contrary, acquire the development of power of other branches, namely, craft productions, to the composition of which the company belongs. The result of the activity of the businesses complex is the formation of significant volumes of food waste (about 160 thousand ton), discharges of concentrated wastewater, wastewater discharges. The wastes of the restaurant industry have a wide nomenclature and a specific composition, under the conditions of their placement in the components of the environment form the ecological aspects of the negative effects. Food wastes of facility in this branch contain a significant amount of nutrients, organic substances and require complex processes of their processing. Meanwhile, according to their composition, production wastes can be involved in the transfer process with the removal of secondary raw materials and energy sources. Thus, there is a need to improve existing and new technologies for the transfer of hazardous waste in order to reduce the load on the environment. The results of the analysis of world and domestic developments in the field of technologies for the utilization of food waste allowed to determine the main methodological approaches to the transition. In the case of the utilization of food waste, biotechnological methods represent a significant interest. Thus, the work is devoted to the connection of the actual scientific-practical task, which consists in the scientific substantiation and improvement of the technology of the transfer of the population's needs.

Environmental and innovation problems of Russia in the context of the transition to an energy efficient economy

The relevance of the study is determined by the fact that the modern ecological situation necessitates the transition of the branches of the national economy from technogenic to sustainable and ecologically balanced development. These processes will be facilitated by the greening of the economy through the modernization of processing industries through the introduction of innovative technological processes that will increase the depth and complexity of processing, which will increase the resource efficiency of the use of hydrocarbons, as well as reduce environmental risks. In the context of an increasing shortage of non-renewable resources, aggravation of environmental problems, introduction of resource-saving and resource-efficient innovative “green” technologies aimed at producing new types of “green” products is a prerequisite for the successful development of the economy and preserving the environment. The novelty of the study is due to the achievement of the “decoupling” effect, which implies an increase in the resource efficiency of the use of raw materials while reducing environmental risks. This implies the creation of such conditions under which, based on the modernization of the economy through innovative technologies that allow meeting the growing needs, the minimization of the use of hydrocarbon resources will be ensured. The most important direction of Russia’s transition to “green development” is to increase the complexity of the use of raw materials, increase the depth of processing, Nelson’s complexity coefficient economically justified extraction of all useful components contained in raw materials and production wastes extracted from hydrocarbon raw materials. The main factor in reducing the burden on the environment, reducing resource intensity is innovative transformations based on the comprehensive use of environmentally friendly low-waste technologies.

Study of possibility of obtaining alternative binders from production wastes for filling man-caused voids

Basic scientific and practical results of the study of possibility of obtaining alternative binders from production wastes to fill man-made voids at underground ore mining are presented. The objective of the study was to determine the technological possibility and economic feasibility of using available low-active substances as substitutes for expensive and scarce cement. It was shown that it is possible to obtain a binder from dolomite wastes, equivalent in properties to cement, which makes it possible to meet the demands of environmentally correct ore mining technologies. It has been established that hardening mixtures based on dolomites and enrichment tailings are only 8-22% inferior in strength to mixtures with standard cement and are suitable without restrictions for the construction of nature protection massifs in mine workings. Recommended activation of wastes increases the strength of the hardening filling mixture by 15-20% in comparison with the basic technology. With additional preparation in activators, a fundamental change in the quality of dolomite products is possible. The use of wastes in the production of a hardening mixture will free up the land occupied by storage facilities and organize the production of competitive products. Alternative binders and inert materials are recommended for use.

Perspective for the use of industrial waste in lubricating compositions to reduce wear in friction pairs

The article presents an analysis of the mechanisms of lubricating action used to reduce the wear of rails and wheels. A review of lubricant compositions that increase the service life of the wheel-rail pair showed that graphite is the main filler used to create rail lubricants. Since the production of synthetic graphite requires high energy costs, this material is relatively expensive. Replacing graphite with cheaper analogs will help reduce the cost of operating rails without losing lubricating properties in friction pairs. Today, there are many lubricant compositions. Many of them require experimental research since they are based only on theoretical knowledge in the field of tribology. In addition, the adhesion properties of a wheel to a rail depend not only on the action of the lubricant but also on weather and climatic conditions. When choosing a rational lubricant, it is worth focusing on a set of factors, and not only on the properties of an individual filler. The data obtained in theoretical analysis cannot always be verified experimentally. The reasons may be economic inexpediency, the complexity of experimental research, or lack of time. The analysis carried out in the course of this work showed that the study of the effect of lubricant components could be optimized using mathematical and digital modeling. The application of these methods will help to select a rational area for research, simulate the behavior of lubricants containing production wastes, and make the mathematical forecast of the operation of friction pairs more accurate.

Using local micro-biota to extract biodegradable plastics from food waste through a natural fermentation process

The main problems of mankind in recent decades are the accumulation of various industrial, agricultural, and food production wastes. Their ineffective disposal and management practices have a detrimental effect on human health and cause environmental pollution, which requires urgent action. Food waste has become a complex phenomenon lately, attracting the attention of scientists, consumers, and activists. This study aims to apply the biotechnology of converting food waste into crystals of polylactic acid (PLA), a monomer for biodegradable plastic. A food waste sample is taken from the student canteen; wash, to remove impurities and fermentation of carbohydrate waste by autotrophic lactic acid bacteria in a natural process for about seven days in the optimal temperature range. Finally, lactic acid molecules polymerized by condensation reaction to form poly L-lactic acid (PLA) crystals, and then a biodegradable bioplastic.

Recovery of Residues of Surface and Emulsion Waste Water Treatment at a Bearing Factory

The directions of utilization of production wastes of the second level, namely, residues of surface and emulsion waste waters treatment of a bearing factory, are given. The results of studies of a new composition of asphalt concrete mixture obtained on the basis of foam, sludge from the treatment of surface water and oily sludge from the treatment of emulsion wastewater from a bearing factory are presented. A technological scheme for the reuse of waste water from surface and emulsion wastewater treatment at a bearing factory has been developed.

Modified Composite Fine-Grained Concrete

The paper presents the findings of the experimental investigation conducted to identify the effect of composite admixtures including a plastifying agent and soot production wastes on the proper-ties of fine grained concrete. The joint effect of the cement and sand matrix and soot wastes was investigated, too. The investigation identified the effect the complex admixture of a plastifying agent and soot wastes on structure formation, physical, mechanical properties and strength of the fine grained concrete. It was found that the micro particles of soot wastes concentrate the grains of the quartz sand around them as well as the products of the new formation of cement stone such as hydrated calcium silicate and others. This ensures a higher density of micro structure and increased strength of the fine grained concrete.

Developing an Industrial Symbiosis of Chemical Industries: a Case Study

The article considers the approaches to building a circular economy based on the example of a functioning Russian industrial hub. Among the features analyzed are the specificities of the industrial symbiosis development of chemical enterprises and material flows that link different technical processes, namely the production of soda ash, lime, salt, and gypsum. This study assesses the pollutant emissions from the new technical processes and the use of accumulated chrome production wastes as secondary material resources. Likewise, the article demonstrates the possibility of direct absorption of carbon dioxide, as a byproduct of lime production during soda ash manufacturing. The study ends with recommendations for considering the aspects for the use of secondary resources in determining the sectoral and inter-sectoral best available techniques. Similarly, it sheds light on possibilities for optimizing the system of technological regulation and general binding rules application for managing insignificant environmental aspects of industrial production.