Use Of Secondary Raw Materials Research Articles

Closed‐loop economics in waste management: financing procedures and results

To analyze the procedure and main results of financial support for the implementation of a closed‐cycle economy in the subjects of the Russian Federation.Statistical data and strategic planning documents. The method of analysing the legal and regulatory framework and statistical reporting, as well as the structure of the federal budget, were used. The study is also based on the application of methods of comparison and contrast, grouping, historical and factor analysis.The key role of the state in the creation and effective functioning of the integrated system of solid municipal waste management (MSWM) is determined by the ability to concentrate the necessary financial resources and guarantee uniform standards and requirements for system participants to achieve the stated goals of the closed cycle economy (CCE). Uniform standards and requirements for system participants must be guaranteed to achieve the stated objectives of the closed cycle economy (CCE). This is confirmed by the results of the financing of the TCO management system for 2019–2023, when the federal budget financed activities to the amount of 42.3 billion rubles. For the purposes of the federal EZC project, 8.6 billion rubles were allocated. It is important to ensure off‐budget financing of these activities and modernization of domestic enterprises, for which the use of secondary raw materials is available and economically feasible. The priority of measures to implement CCE in the Russian Federation is financial support for the creation and development of infrastructure for waste collection and recycling.The processes on improvement of the regulatory and legal framework and personnel training are related to the need to implement a "top‐down" approach, which determines the centralisation of decision‐making and the efficiency of attracting extrabudgetary funds dominating in the financial support of the functioning of the TCO management system and implementation of CCE.

Reasons and consequences of historical buildings and structures fragments' reuse

The article examines the peculiarities of the use of secondary raw materials in architectural and urban planning activities. The conducted research showed that the use of secondary raw materials is an established practice in architectural and urban planning activities. Surviving but no longer needed buildings and structures, their ruins, individual fragments of former architectural and urban planning objects, and construction materials extracted from them are subject to reuse. Pragmatic saving of time and materials is not the only reason for the integration of used elements in new buildings. Among the other conditionally positive driving motives of this practice: attempts to strengthen the political ambitions of modern powerful people, to draw symbolic parallels between different religions, to realize their own creative ambitions, to preserve the fragments of destroyed culture, and to perpetuate the collective memory of the inhabitants of certain territories. Unfortunately, the history of architecture preserves evidence that the re-use of architectural fragments can also be motivated by opposite, conditionally negative goals, such as contempt for the conquered state; contempt for another religion; superiority to the destroyed culture; fear of deposed but creepy mythical creatures; hatred of the persecuted people. The outlined motives determine the nature of behaviour with secondary raw materials and the result of its use. Respect and willingness to study lost objects of cultural heritage leads to the emergence of new interesting and meaningful architectural and urban planning solutions. Indifference, self-assertion, and aggression increase chaos and insensitivity to beauty and cause inappropriate project decisions, for which descendants are later ashamed. Because of the application of recycling practices in architectural and urban planning activities, historical buildings and structures do not lose their identity, acquiring a new symbolic meaning; turn into archaeological artefacts with an unknown past, or as depersonalized raw materials dissolve into newly created objects.

Study of the characteristics of pavement elements made of reinforced soil with the use of secondary resources

The importance of using secondary resources on the basis of industrial waste is understood by both governments of developed countries and business (production of Portland cement using ground metallurgical slag as a mineral additive at Novotroitsk, Magnitogorsk, Sterlitamak, KatavIvanovsk and other plants in the South Urals). The use of secondary raw materials requires the creation of technological infrastructure for processing of secondary raw materials, the costs of which can be quickly recouped due to the cheapness and availability of industrial secondary raw materials and freeing the territory from environmental pollution. In order to recoup the costs of the infrastructure, it is necessary to guarantee full compliance of the quality of pavement elements with the requirements of GOST R 59120-2021. Secondary raw materials have a great variety and laboratory analysis of the quality of pavement elements is required in order to design compositions with the best quality, satisfying all regulatory requirements. In our work the authors present the results of laboratory research and evaluation of the possibility of using clinker-free lime-slag binder based on the mineral product of soda production and metallurgical slags to strengthen and stabilize soils for their use in pavement structures in the construction of roads for various purposes and climatic zones. It is experimentally shown that the addition of lime-slag binder in the amount of 8-10% of the dry weight of both cohesive (loamy soil, loamy sand) and non-cohesive (fine sand) soil allows to obtain reinforced soil with improved strength and elastic-deformative characteristics, which can be used instead of scarce natural crushed stone and gravel in the construction of underlying layers of pavements in the construction and reconstruction of highways. This technology can be used not only in the Russian Federation, but also in a number of other countries, including those with hot dry climates (e.g., the Republic of Egypt).

Recycling of poly(lactic acid)/poly(butylene succinate) (PLA/PBS) blends with high amounts of secondary raw material

AbstractIn this study, the mechanical recycling of poly(lactic acid)/poly(butylene succinate) (PLA/PBS)‐based formulations with additives was investigated. A simulation of mechanical recycling was performed using secondary raw materials in the analyzed formulations (at very high levels >30%). The recycling process was simulated by repeating extrusion cycles on the compound to produce aging under accelerated conditions, similar to those that normally occur during the extrusion compounding of the bioplastic material. The formulations were characterized by using differential scanning calorimetry (DSC), heat deflection temperature (HDT), melt flow rate (MFR), Fourier transform infrared spectroscopy (FTIR) and UV–vis spectroscopy. The aim of the work was to study the efficiency of a multi‐epoxy chain extender in mechanical recycling of PLA/PBS blends. The results showed that the use of secondary raw materials did not cause drastic changes in the thermal properties and chemical composition of the blends, which indicates that they are suitable for manufacturing bioplastic blends. Specifically, MFR results showed a major efficiency of the chain extender in samples having PLA as primary polymeric phase, whereas no change was observed in formulations where PBS is the main phase with the addition of a higher amount of chain extender.

Investigation of the role of impurities typical in secondary raw materials on the behaviour of high alumina castables - Part II: Influence on thermomechanical behaviour

The present work investigated the effect of relatively small additions of impurities originating in secondary raw materials on the thermomechanical properties of alumina castables bonded with active alumina. Castable compositions containing impurities for testing were selected on the basis of predictions from thermochemical calculations of their phase composition and the formation of large amounts of liquid phase at the temperature of 1600 °C. Viscosity of the emerging liquid phase was also calculated. The selected alumina castables with impurities from the systems: CaO–SiO2. Na2O–SiO2. Fe2O3–CaO. Fe2O3–CaO–SiO2 and TiO2–CaO–SiO2 were tested for thermomechanical properties by analysing the effect of impurities on refractoriness under load (RUL) creep in compression (CiC) and resonant frequencies and damping changes versus temperature (RFDA). Real composition of tested material via high temperature X-ray diffraction (HT-XRD) were verified. The obtained results indicate that impurities introduced into the refractory castables in a total amount of 0,18 wt% (2% in the fraction 0–45 μm) and in the most unfavourable ratio from the point of view of phase equilibria have an observable effect on the properties of the material at elevated temperature. The obtained results show that in the case of introducing impurities into the material with mutual proportions of shares limiting the formation of the liquid phase. It will be possible to maintain the thermomechanical properties of alumina castables at a satisfactory level (compared to the pure one) from the industrial process perspective in which it will be used. The obtained results shed new light on the possibilities of the conscious use of secondary raw materials in refractory monolithics technology.

Automated Study of Electrophysical Properties of Polymeric and Composite Materials

The use of secondary resources and composites in modern polymer materials would make it possible to reduce the cost and change the physical and mechanical properties of the packaging material. The use of composites to impart new properties to polymers complicates the implementation of technologies for the production of products from them, which prevents the improvement of product quality. This is due to the lack of an accumulated database and methods of predictive determination of the obtained properties of composite materials and polymers produced with the use of secondary raw materials. (Research purpose) The research purpose is testing the methodology of automated determination of electrophysical parameters of polymer and composite thermoplastic materials. (Materials and methods) A resonant method of monitoring the electrophysical parameters necessary for an energy-efficient method of high-frequency electrothermal heating of polymers has been substantiated. We selected and modified with the installation of an automated monitoring and data collection system cumeter with a working chamber from a standard cell, retrofitted with a heating system and thermal insulation. (Results and discussion) The results of the use of an automated process of control and determination of electrophysical parameters of polymer and composite materials based on polypropylene, polyethylene with a composite of titanium dioxide were presented. The method of establishing analytical dependencies for calculating the correction coefficient when calculating the effect of thermal insulation material (dielectric cardboard) and air gap in the working capacitor on the even electrophysical parameters of the polymer and composite under study was shown. (Conclusions) The possibility of conducting automated studies to determine the dielectric properties of polymer and composite materials using the developed automated control system for the process of control, transmission, processing, visualization and storage of information about the dielectric properties of ε, ε», tgδ polymer and composite materials was substantiated. The heating temperature ranges of polymer and composite materials PP H030 GP/3 TS and 1060PE were identified in automatic mode in order to organize the most energy-efficient operating modes of high-frequency electrical equipment.

Biochemical composition of ciders from various raw materials

Apple tree is the most common among other fruit crops. Apple fruit is the primary raw material used in cider making. Although the majority of Russian regions are rich in raw materials for the production of high-quality cider, the development of this industry is hampered by a number of issues. As a result, the domestic market sometimes offers low-quality and adulterated products. In this work, we study the organoleptic and biochemical indicators (volatile components, metal cations, phenolcarboxylic acids and organic acids) of fermented diffused apple juice and ciders prepared from both freshly squeezed and reconstituted apple juice. The biochemical composition and organoleptic characteristics of samples were determined by conventional methods, such as high-performance liquid chromatography (organic acids), capillary electrophoresis (phenolcarboxylic acids) and gas chromatography (volatile components). The concentrations of most of the studied parameters and organoleptic indicators werehigher in ciders from fresh apple juice. However, in the fermented diffused juice, the concentrations of chlorogenic (9.5 g/dm3), orotic (1.9 g/dm3) and gallic (4.7 mg/dm3) acids, as well as furfural (11.84 mg/dm3), exceeded those in other studied samples. Future research should investigate the possibility of secondary use of apple pomace, e.g., for the production of fruit spirits. Involvement of such raw materials ensures the rational use of secondary raw materials.

Sorting, Characterization, Environmentally Friendly Recycling, and Reuse of Components from End‐of‐Life 18650 Li Ion Batteries

AbstractThe rapid growth in demand for lithium‐ion batteries (LIBs) is posing challenges in the management of end‐of‐life (EoL) systems and the supply of critical raw materials (CRMs), especially lithium, cobalt, and nickel. Such challenges can be addressed by collecting and recycling spent LIBs through economically and environmentally sustainable processes and by enabling the transition to a circular economy vision based on the use of secondary raw materials. These processes involve not only the metallurgic approaches to recover the critical metals, but also the pretreatment approaches that are crucial to enhance the recovery efficiency of other valuable materials (e.g., graphite, fluorinated compounds, binders, electrolyte). Herein, pretreatment processes ranging from the disassembling, opening, and sorting to the component separation, collection, and recovery, are described for the EoL 18650‐type commercial LIB. A closed loop of eco‐friendly recycling to fully recover the composite cathode, i.e., the cathode active material (CAM), the fluorinated binder, and the conductive carbon, as well as the separator, is presented. The recovery approach is based on green solvents and is designed to limit water consumption. The recovered materials are used to assemble a new cell, and the electrochemical characterization is used to evaluate the effective feasibility of the whole recycling process.

STUDY OF THE SAFETY INDICATORS OF OILSEED CAKES

The purpose of this research is the use of secondary raw materials of oil and fat industry enterprises, oilseed cake, for the development of new enriched food products with increased biological and nutritional value. The objects of research were flaxseed, soybean, peanut, and pumpkin oilcake obtained based on an experimental production workshop for the processing of oilseeds. This article presents the results of organoleptic, physico-chemical, and microbiological indicators, the content of toxic elements, the content of heavy metals, and the energy value of the studied cakes for further use in the development of bakery, confectionery, and pasta products was determined. All indicators do not exceed the requirements established by regulatory documents. According to the results of the research, high content of proteins from 29.6 in peanut and up to 37.5 in pumpkin oilcake was revealed; toxicity in rabbits was not detected, cadmium, mycotoxins, Bacteria of the Escherichia coli group BECG (coliforms), yeasts, molds were not detected; other toxic elements, the number of mesophilic aerobic and facultative anaerobic microorganisms (NMAFAM), heavy metals do not exceed the allowable limits.Domesticoilseed processing by products can enable the reuse of materials in the supply chain as they add value to food, reduce costs, promote economic growth, and reduce the risks associated with their disposal in the environment.

PGNAA Spectral Classification of Metal With Density Estimations

For environmental, sustainable economic and political reasons, recycling processes are becoming increasingly important, aiming at a much higher use of secondary raw materials. Currently, for the copper and aluminium industries, no method for the non-destructive online analysis of heterogeneous materials are available. The Prompt Gamma Neutron Activation Analysis (PGNAA) has the potential to overcome this challenge. A difficulty when using PGNAA for online classification arises from the small amount of noisy data, due to short-term measurements. In this case, classical evaluation methods using detailed peak by peak analysis fail. Therefore, we propose to view spectral data as probability distributions. Then, we can classify material using maximum log-likelihood with respect to kernel density estimation and use discrete sampling to optimize hyperparameters. For measurements of pure aluminium alloys we achieve near perfect classification of aluminium alloys under 0.25 second.

The potential of unclaimed forest resources of the Krasnoyarsk Territory and the prospects for their use

The timber industry is one of the oldest industries in Russia, associated with the harvesting and processing of wood. It is responsible for the stock of wood, its removal, primary processing and waste disposal. On the territory of the country there is 1/4 of all the world’s timber reserves, the volume of timber harvesting is estimated at hundreds of millions of cubic meters. An integral part of the logging process is the generation of waste, the volume of which is directly related to the volume of logging operations. Every year in the Russian Federation, 35.5 million m³ of wood waste is generated, which worsens the ecological situation. Forest fires and insect pests are also one of the main causes of the weakening and death of forests. Areas with abandoned wood, affected plantings require priority development, and low-quality wood should be recycled to obtain recyclable materials. The introduction of resource-saving, environmentally friendly and efficient technology, which provides for the processing of waste and the use of secondary raw materials, will help minimize the negative impact of unclaimed wood on the environment.

Scientific rationale for reducing the negative impact on the environment of grain processing industries through the rational use of secondary raw materials

At various stages of grain processing, grain waste, husks, crushed grain, chaff, flour, etc. are formed, which account for up to 19% of all food losses and waste in the world. They are a source of possible pollution of both industrial premises and the environment. Most grain processing wastes are secondary raw materials with high nutritional and biological value. Currently, processing industry enterprises are introducing elements of low-waste and waste-free technologies that allow the complete extraction of valuable components of grain processing waste, thereby significantly reducing the damage caused to the environment as a result of their emissions. The most promising and environmentally friendly technologies for the Russian Federation are technologies for deep processing of grain, and, in particular, pea grain.

Expanded Glass for Thermal and Acoustic Insulation from Recycled Post-Consumer Glass and Textile Industry Process Waste

The production of glass foams obtained by recycling post-consumer glass and textile industry processing waste is presented. The mechanical, thermal and acoustic properties were characterized as a function of process temperature and time. The results showed that it is possible to produce glass foams with thermal and acoustic insulation properties from a mixture consisting of 96.5% of glass waste, 1% of textile waste and 2.5% of manganese dioxide, processed at temperatures between 800 and 900 °C for a time between 30 and 90 min. The samples had density in the range of 200-300 kg m-3, porosity of 87-92%, thermal conductivity of 85-105 mW m-1 K-1, noise-reducing factors of 0.15-0.40 and compressive strength of 1.2-3.0 MPa. Although their insulation performance was not as outstanding as that of polymer foams, these materials can emerge as competitive candidates for applications requiring non-flammability and high-temperature load bearing capacity in combination with low weight, mechanical strength, and thermal and acoustic insulation properties. The use of secondary raw materials (which accounted for 97.5% by weight of the synthetic blend) limits the energy required compared to that needed for the extraction, transportation and processing of primary raw materials, making these foams attractive also in terms of environmental footprint.

Potential for Increased Use of Secondary Raw Materials in the Copper Industry as a Countermeasure Against Climate Change in Japan

The copper industry faces serious challenges in achieving the dual goals of mitigating climate change and developing a circular economy, as the increased use of secondary raw materials could increase CO 2 emissions during the smelting stage. This study aimed to examine the possibility of increased use of secondary raw materials (copper scrap and waste from electrical and electronic equipment (WEEE) substrates) in the Japanese copper industry as a countermeasure to climate change. We comprehensive analyzed the changes in CO 2 emissions and costs associated with increased use of secondary raw materials compared to the use of primary copper resources by establishing an intensity at each stage within the system boundary. The analysis results established that CO 2 emissions can be reduced but costs may increase, and that purchasing carbon credits is economically more advantageous. It was also established that the results will vary depending on how CO 2 emissions and costs are allocated because multiple metals can be recovered from WEEE substrates and that the carbon footprint of all‑copper allocation will be significantly lower in the future because of the expected development of decarbonization technologies, including transportation. The study results indicate the potential of the copper industry to expand its use of secondary raw materials from a climate change perspective. CO 2 emissions resulting from the increased use of secondary raw materials in the Japanese copper industry.

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The demand for confectionery products is constantly growing, so a task has been set up to justify the use of secondary raw materials obtained from the first extract fruit and vegetable juices in the production of cupcakes. The use of fruit and vegetable powders will enable to expand the product range of flour confectionery, as well as to enrich the finished product with dietary fibers and vitamins. Apple and parsnip pulp were subjected to primary research, and their nutritional value was determined. The chemical and vitamin indicators of the finished products were determined according to the research methods regulated by GOST. Then, comparative evaluation of the vitamin value of apple and parsnip pulps was made. According to research results, fruit and vegetable pulp is not inferior in nutritional value to the original raw material, only certain losses occur during juice extraction process. In order to obtain fruit and vegetable powders and possibly preserve their valuable components, the convectivemicrowave drying method was used, which prevents microbial spoilage and deactivation of enzymes in the pulp. After drying, the content of vitamins, chemical and mineral substances in the obtained powders was studied. The addition of 10-15 % fruit and vegetable powders in the production recipe of cupcakes improves the physicochemical indicators of the finished product. Cupcakes made with the supplementation of fruit and vegetable powders also have a low energy value and contain a large amount of pectin substances. Therefore, we recommend using these powders in the manufacture of other products as well.

Circular economy model: generating benefits for sustainable development

The article is devoted to the definition and analysis of the circular economy as the basis for sustainable development of the country. The author identifies the main differences between the circular economy model and the traditional model, characterised by close interconnection and interdependence of all industries, production links and trade and consumer relations, which ensures maximum benefit from available resources. The principles of the circular economy are considered and the main advantages and disadvantages of the circular economy model are revealed. The economic advantages of the closed-loop economy include the formation of a sustainable demand for secondary material resources (and, as a result, a reduction in demand for primary resources in the long term); creation of economic incentives for further investment in the use of secondary raw materials due to the exhaustion of primary material resources; reduction of costs for the maintenance of waste storage areas; and reduction of environmental taxes. The environmental benefits of the circular economy are represented by reduced carbon dioxide emissions; reduced landfill and waste storage areas; reduced consumption of scarce and limited resources, etc. Social benefits are due to an increase in the level of social responsibility for the careful use of material resources; ensuring an environmentally friendly attitude to used goods; an increase in the number of jobs for secondary material resource technologists, etc. Examples of the implementation of the basic principles of the circular economy are given, and thanks to the involvement of new business models, technological enterprises have become able to comply with the principles of the closed-loop economy. The national peculiarities of Ukraine's transition to the circular economy model are analysed.

THE IMPORTANCE OF EDUCATION ON MINERAL RAW MATERIALS FOR MORE SECURE AND ENJOYABLE TOMORROW

Mineral raw materials represent the basis for our everyday goods, e.g. food, cosmetics, clothing, medicine, mobile phones, electrical appliances, vehicles, construction materials, fertilizers, jewellery, etc. Furthermore, mineral raw materials are essential for new solutions for modern infrastructure and technologies and are indispensable for reaching the Green Deal goals of a climate-neutral society by 2050. In fact, the more ambitious climate targets are, the more minerals are needed for clean energy transition. Since the mineral consumption in general is rising, there is a need to educate society, especially children, on these topics. School curriculums often lack these topics, in particular while addressing recycling and circular economy. The RISBriefcase project, with its non-conventional teaching tools, is applying the holistic approach on this matter by teaching children about mineral properties and their uses, critical raw materials, circular economy approaches and use of secondary raw materials, sustainable mining, gender equality and a variety of career opportunities in mining sector.

Review of modern scientific developments in the field of molybdenum recovery from spent catalysts

The widespread use of rare metals in industry requires an increase in the amount of their production and expansion of methods for obtaining them. In this regard, the use of secondary raw materials in modern production is growing rapidly and steadily. Molybdenum is a refractory metal, which is used as an alloying element in various steels, heating elements of electric furnaces, special purpose alloys, electrovacuum equipment and other fields. Data on the volume of consumption of catalysts in the oil refining and petrochemical industries, as well as on the import of molybdenum-containing catalysts are given. The technologies for processing spent hydro-treating catalysts with production of molybdenum oxide are considered, including oxidative roasting of the feedstock, as well as such operations as: leaching by sulfuric, hydrochloric, and nitric acids, sodium carbonate [7]. Hydrometallurgical methods of decomposition of raw materials are usually combined with the subsequent extraction of molybdenum by extraction with citric acid [16], MTAA carbonate [15], or ion-exchange sorption. High purity molybdenum is characterized by a number of unique properties that are important for its use in modern technology. Most of the hard-to-remove impurities get into molybdenum oxide from the feedstock, so one of the important tasks is to optimize the leaching process at the stage of uncovering of technogenic raw materials. Recently, more and more attention has been paid to obtaining high-purity molybdenum oxide, as well as to the separation of molybdenum and tungsten. One of the promising processes seems to be ion exchange, which makes it possible to purify solutions from metal impurities from solutions and pulps formed during the decomposition of molybdenite concentrates or during leaching of raw materials. The review was carried out under the agreement between the National University of Science and Technology “MISiS” and JSC “Company Wolfram” (Moscow region, Russia) No. 0422-341 dated April 22, 2021, implemented with the financial support of the Ministry of Science and Higher Education of the Russian Federation by order of the Government of the Russian Federation No. 218 of 04/09/2010.

Catalogue of construction products containing secondary raw materials from different industries and municipal waste

The building industry consumes a large amount of primary raw materials and also contributes significantly to the production of waste. Applying circular principles in this field to reduce resource consumption and waste production has been investigated in several projects considering the reuse or recycling of construction and demolition waste. However, consumption of primary raw materials can also be reduced by re-targetting waste from different industries and municipal waste to produce new construction products. Thus, opportunities for the recycling of industrial and municipal waste were investigated in this project. The main output is the catalogue, which provides an overview of products with recycled content and secondary materials with the potential to be used in the construction industry such as blast furnace slag, ash, and energy by-products. Also, it contains a list of valid requirements for the use of recycled materials under specific conditions of the Czech Republic. In addition, examples of good practice are presented to break the existing behavioral barriers to the use of secondary raw materials in the Czech construction industry. This contribution summarizes the findings in the field of industrial and municipal waste recycling and its further use as secondary raw materials in the construction industry.

Pavement Bases from Recycled Materials

Road bases are the main bearing layers of the road pavement, the purpose of which is the perception of the load from cars and its distribution on the subgrade soil. The base structure is determined by calculation depending on the planned traffic load and traffic intensity and usually consists of two layers, and for capital coatings, the upper layer of the two-layer base is made of materials reinforced with binders. The base of the pavement is a rather expensive construction and it is important for its construction, where possible, to use local materials, as well as secondary materials, i. e. industrial and construction industry waste.  In the process of construction and repair works, the use of secondary raw materials can significantly reduce the cost of their implementation. Moreover, this practice not only reduces the cost of work, but also reduces the negative impact on the environment. The paper considers the possibility of constructing a pavement base from such secondary materials as spent molding sands (foundry waste), cement granulate (a product of crushing old cement concrete structures, construction waste) and asphalt granulate (a product of milling worn asphalt concrete pavements). In this case, the cost of the base is significantly reduced  while еnsuring its necessary strength. Spent sands were used as a leveling layer, cement granulate