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Wind turbine blades are primarily composed of fiberglass composite, posing a significant recycling challenge for the wind energy industry. This paper introduces a novel recycling approach by comprehensively analyzing the pozzolanic reactivity of recycled powder as a new supplementary cementitious material (SCM). A systematic characterization using laboratory techniques is first described, establishing both the chemical and morphological properties of the powder and suggesting that the material was likely to be capable of acting as a pozzolan. The effects of thermal and mechanical processing on the reactivity characteristics of the material were elucidated using a suite of analytical and standardized characterization approaches. It was found that through heat treatment to remove impinging resin and subsequent mechanical processing to synthesize a fine powder, the reactivity of the material could be improved to an extent at which the performance characteristics of a conventional class F fly ash were closely matched. For instance, mortar containing 10% of thermally-mechanically processed powder achieves 95% of the 28-day strength of cement mortar. This paper opens the door for both the use of these materials to bolster dwindling supplies of supplementary cementitious materials, and to provide a much-needed reprocessing route for waste fiberglass which are otherwise highly challenging to dispose of cost-effectively. [ABSTRACT FROM AUTHOR]

The present study deals with the reuse of agro-industrial waste with a specific focus on biochar (processed plant biomass or biochar) consisting of organic and inorganic waste biomass subjected to thermochemical processes. The objective of this work is to carry out a systematic review of the literature according to the Methodi Ordinatio methodology and select a bibliographic portfolio of high relevance to this study that makes it possible to present the concepts, applications and interest on the part of companies in including biochar in their processes, as well as addressing the environmental impacts linked to incorrect waste disposal. In this sense, biochar presents an interesting potential solution from both a waste management and environmental point of view. The current challenge is studies that prove economic viability.

Baitul Qur'an Islamic Boarding School Campus 3 which is located in the West Rumbai District Area, including Pekanbaru City, this campus has a very extensive educational environment so it is necessary to carry out maintenance to maintain the cleanliness of the boarding school, especially for students who may not have knowledge about classifying types of waste and the processor. For this reason, the service team wants to provide education on the introduction of types of waste and their processing. This outreach activity was attended by students, especially at the Aliyah and MTs levels. In the pretest, the percentage of participants who understood various aspects of waste management ranged from 12% to 76%, with the lowest understanding in electronic waste management and the highest in the definition and types of waste. After the counseling was carried out, the results were that participants were very enthusiastic in this activity, so that in the posttest activity the results were 100% of the 25 participants understood the activities carried out.

The present study deals with the reuse of agro-industrial waste with a specific focus on biochar (processed plant biomass or biochar) consisting of organic and inorganic waste biomass subjected to thermochemical processes. The objective of this work is to carry out a systematic review of the literature according to the Methodi Ordinatio methodology and select a bibliographic portfolio of high relevance to this study that makes it possible to present the concepts, applications and interest on the part of companies in including biochar in their processes, as well as addressing the environmental impacts linked to incorrect waste disposal. In this sense, biochar presents an interesting potential solution from both a waste management and environmental point of view. The current challenge is studies that prove economic viability. [ABSTRACT FROM AUTHOR]

The reprocessing of mining waste remains a challenge to achieve ecological sustainability. Magnetic separation is one of the most effective methods for physical separation of materials. In this research, a magnetic separator with permanent neodymium (Nd-Fe-B) magnets is developed to remove magnetic particles contained in mining waste powder. Experiments with different variables were carried out to determine the design parameters for the process, such as: the separation between magnets, the flow of the material and the concentration of solids in the slurry. In this investigation, a Taguchi L16 4k matrix was used, considering that the process has 3 controllable factors with 4 levels each, for which 64 samples were prepared to obtain the parameters that give us a process that works with greater consistency, considering 2 noise factors (% of magnetics in the sample and the accumulation of particles). The results of this research will be the basis for the manufacture of a magnetic separator for the treatment of mining waste. [ABSTRACT FROM AUTHOR]

This review explores different methods of sustainably introducing nutrients from agro-industrial waste into the soil. The focus is on sustainable agriculture and how the soil system can be modified by introducing secondary raw materials and beneficial microorganisms. Soil is a nexus between plants and microorganisms that must be balanced. The article emphasizes the importance of maintaining the microbiological balance when supplying nutrients. This review is focused on the possible techniques involved in the production of biofertilizers and their mode of application into the soil system and on plants. We addressed several advantages concerning the use of beneficial microorganisms in waste management by microbial formulation techniques. Not only the advantages but several limitations and challenges were also discussed in regard to the large scale production of microbial products. Therefore, the proper treatment of industrial waste is essential so that we can preserve the environment and human safety and also achieve sustainable agriculture. [ABSTRACT FROM AUTHOR]

Relevance. At present, the problem of soil pollution with heavy metals, which are accumulated in the body of animals and plants, causing various toxic effects, is especially acute. Despite the existence of various methods of reclamation of disturbed lands, as a rule, their application is inefficient or expensive, especially when it comes to abnormally high concentrations of heavy metals. Thus, an extremely urgent task is to find effective and inexpensive ways to recultivate lands contaminated with high concentrations of heavy metals. The article considers one of the promising areas for the reclamation of such lands using a mixture obtained from the accumulated waste of lignin-containing sediments from the pulp and paper industry of Baikal Pulp and Paper Mill as sorbents. Aim. To study and evaluate the effectiveness of using a mixture, which includes frozen lignin-containing sediments of Baikal Pulp and Paper Mill, as heavy metal sorbent. Methods. To assess the sorption efficiency of the obtained sorbent from the frozen sediments of sludge-lignin, the samples of anomalously contaminated soils were taken from the industrial site of the former battery plant "Vostsibelement", located in Svirsk, Irkutsk region. To determine the surface structure of the obtained sorbent for the presence of micro-, meso-, and macropores, its surface was surveyed using a JEOL two-beam system. IR spectroscopy was used to establish the types of bonds between the sorbent and the extracted metals. Results. The studies have shown that the resulting sorbent from the frozen lignin-containing sediments of Baikal Pulp and Paper Mill has a porous structure with a predominance of mesopores, sorbing heavy metal ions, while a large number of micropores contributes to the occurrence of chemical sorption. The obtained IR spectra indicate the possibility of chemical sorption of lead as a result of the reaction of substitution of a hydrogen atom in various hydroxyl groups of the sorbent of the group of aromatic or carboxyl structures. At the same time, the resulting sorbent in terms of its sorption properties is not inferior to commercial natural sorbents – bentonite clay and grassroots peat. The conducted studies allow us to make a positive conclusion about the possibility of using the developed mixture as a sorbent for the immobilization of heavy metals during the reclamation of lands that are contaminated with high levels of heavy metals, including lead.

Plastic waste generation in India was around 9.4 million tonnes.year−1 in 2019 as compared to the global generation rate of more than 380 million tonnes.year−1 in 2019. Thus, India's contribution was around 3.1% of the global plastic waste generation. Globally, 42% of overall plastics produced are consumed by packaging sector and 17% by the construction sector. Whereas in India 35% is consumed by the packaging sector and 23% by construction sector. Bioplastic production is 1% out of 300 million tonnes of conventional plastics produced annually. This review attempts to analyse the plastic waste management rules, legislations, policies and practices in India during the period 1992–2020. The worldwide trend of bioplastic projects is reflected in studies in India, indicating a changed perception of bioplastics as an alternative source to conventional plastics. However, facilitating the implementation of conventional waste plastic processing plant and production of bioplastics in India involves challenges in terms of technology, developing a standardised framework and financial incentives. A legislative framework for the production of bioplastics in India should be developed alongwith an action plan for energy recovery from plastic waste. Markets for conventional plastic waste processing and production of bioplastic projects are not mature in India. This paper addresses the need for developing a roadmap towards efficient planning and sustainable solutions for both conventional plastics and bioplastics. [ABSTRACT FROM AUTHOR]

Besides the generation of aggregates, recycling of mixed construction and demolition waste leads to a more polluted side stream accounting for up to one third of the input materials. This so‐called crushed sand often ends up in landfills and is hence lost for a circular economy. This article reports about the processing of this material using a pilot plant jig. The suitability of jigging technology is evaluated, and the product is analyzed as possible circular building material. [ABSTRACT FROM AUTHOR]

Abstract The jabuticaba bark is rich in anthocyanins and fibers, and its use may be of industrial interest. In the food sector, its used as an ingredient in the production of fermented products, liqueurs or enriched flours. It also has pharmaceutical and cosmetic applications. The objective was to evaluate the effect of pretreatment and fresh use of jabuticaba peels in the extraction of total phenolic compound (TPC) and total anthocyanin (TA) contents with and without ultrasound assistance and in the sequential extraction of pectin from the residue. In the TPC and TA extraction, a 3x2 factorial design was used. For conventional anthocyanin extraction (CAE), occurred in an incubator under agitation. For ultrasound-assisted anthocyanin extraction (UAE) was utilized an ultrasonic homogenizer with probe (20 kHz, 160 W). The extracts were quantified (TPC, TA, antioxidant activity and color). The residues were characterized and used for sequential pectin extraction, which was quantified and characterized. The results were subjected to analysis of variance. Fresh jabuticaba peel is a residue that can be used to sequentially extract phenolic compounds, particularly anthocyanins and pectin. The use of ultrasound (UAE) was less efficient than CAE for extracting TPC and TA or performing sequential extraction on all pretreatment peels.

In recent years, carbon fibres have been extensively used to strengthen concrete structures. In most cases, the lamination process is carried out using epoxy resin as matrix. In some cases, especially when strengthen structural elements made of weak concrete, it is possible to replace the epoxy resin with an inorganic, cement matrix, while at the same time maintaining a sufficient efficiency of strengthen understood as the percentage increase in the compressive strength of concrete samples due to the applied reinforcement in relation to the reference concrete. In these studies, elements of carbon fibres mats that are reinforced with a cement matrix were used as the starting product for fibre recovery. The laminate, which was used to reinforce concrete elements, was detached from the concrete surface and subjected to processing in order to obtain clean carbon fibre scraps without cement matrix. Then, the obtained carbon material, in shaped form, was used to strengthen self-compacting, high performance, fibre reinforced concrete (SCHPFRC). For comparative purposes, this concrete was also strengthened by carbon fibre mats (with one and three layers of CFRP). Each samples were tested in uniaxial compression test. The compressive strength of concrete reinforced with 1 and 3 layers of CFRP was higher by 37.9 and 96.3%, respectively, compared to the reference concrete. On the other hand, the compressive strength of concrete reinforced with 1 and 3 layers of carbon fibre scrapswas higher by 11.8 and 40.1%, respectively. Regardless of the reinforcement technique used, the composite elements showed a higher deformability limit in comparison plain concrete. The obtained results showed that it is possible to reuse carbon fibre to strengthen structural elements made of SCHPFRC effectively, using simple processing methods.

This service activity aims to foster knowledge, attitudes and skills of high school students regarding waste management and its application to organic vegetable cultivation. The community service is carried out through training which consists of the preparation, implementation and evaluation stages. The target partners for this service are SMAN 2 Kota Batu students with a total of 359 students. The evaluation instrument used a questionnaire and was then analyzed descriptively. The results of the service show that this activity has succeeded in growing students' knowledge and skills in processing organic waste into compost and planting organic vegetables from the compost produced. The results of the activity evaluation show that students have been able to carry out waste processing and planting organic vegetables properly and correctly according to the takakura method. The indicator of the success of this service is the increasing of students' skills in processing organic waste and planting organic vegetables. This has been proven by the success of students in processing organic waste at home and the many plants that have been successfully developed from the results of processing organic waste.

A method is proposed for the heat treatment of solid carbon residue from the pyrolysis of rubber products in an oxygen-free atmosphere, so as to improve its quality and expand its practical applications. The initial residue and the heat-treated residue are studied by electron microscopy, IR spectroscopy, and X-ray phase analysis. [ABSTRACT FROM AUTHOR]

As part of the work, the chemical interaction of finely ground glass (~1 μm), calcium oxide, and water was studied. It is shown that an increase in the fineness of grinding makes it possible to abandon autoclave hardening in the production of products on a hydrosilicate binder. The study of chemical interaction was carried out by calculating the thermodynamic equilibrium and was also confirmed by XRD analysis. DTA analysis showed that an increase in the treatment temperature leads to an increase in the proportion of the reacted phase at the first stage. Subsequently, phase formation is associated with the presence of CaO. The carrier of strength characteristics is the CaO×2SiO2×2H2O phase. The selection and optimization of the composition make it possible to obtain a high-strength glass concrete material with a strength of about 110 MPa. The micrographs of the obtained samples correspond to classical hydrosilicate systems. [ABSTRACT FROM AUTHOR]

The article analyzes the impact of microplastics on the environment. Special attention is paid to the research related to the use of plastic packaging in the food industry and hospitality. To fully assess the health impact of our global plastic addiction, one must consider not only each stage of its life cycle, but all possible pathways of exposure to the various substances used and released throughout that life cycle. The study of the attitude of young people to the problem of environmental pollution was conducted, namely, the survey of 174 respondents aged 18 to 23 (43,2 % – men, 56,8 % – women). Most of the respondents are not aware of the real magnitude of the problem, because microplastic waste is still ignored by social advertising, which popularizes the solution to the global problem of pollution, without focusing on the negative effects on human health. Despite the fact that people consume a large amount of microplastics, it is currently difficult to say how it affects our bodies. Many studies are conducted at an insufficiently qualitative level, therefore they do not provide reliable information. Other data are not systematized and do not allow to see the full picture of the problem. It is substantiated that one of the right ways to reduce the negative impact on the environment, in contrast to disposal in specially designated landfills, is recycling and reuse of plastic. Such recycling is facilitated by the separate collection of waste, which currently takes place in Ukraine without appropriate legislative support and incentive measures.

This review explores different methods of sustainably introducing nutrients from agro-industrial waste into the soil. The focus is on sustainable agriculture and how the soil system can be modified by introducing secondary raw materials and beneficial microorganisms. Soil is a nexus between plants and microorganisms that must be balanced. The article emphasizes the importance of maintaining the microbiological balance when supplying nutrients. This review is focused on the possible techniques involved in the production of biofertilizers and their mode of application into the soil system and on plants. We addressed several advantages concerning the use of beneficial microorganisms in waste management by microbial formulation techniques. Not only the advantages but several limitations and challenges were also discussed in regard to the large scale production of microbial products. Therefore, the proper treatment of industrial waste is essential so that we can preserve the environment and human safety and also achieve sustainable agriculture.

Bioregenerative life support systems (BLSS) are vital for long-duration and remote space missions to increase mission sustainability. These systems break down human waste materials into nutrients and CO2 for plants and other edible organisms, which in turn provide food, fresh water, and oxygen for astronauts. The central idea is to create a materially closed loop, which can significantly reduce mission mass and volume by cutting down or even eliminating disposable waste. In most BLSS studies only a fraction of the resources, such as food, are provided by the system itself, with the rest taken on board at departure or provided through resupply missions. However, for autonomous long-duration space missions without any possibility of resupply, a BLSS that generates all resources with minimal or no material loss, is essential. The goal of this study is to develop a stoichiometric model of a conceptually fully closed BLSS that provides all the metabolic needs of the crew and organisms. The MELiSSA concept of the European Space Agency is used as reference system, consisting of five interconnected compartments, each inhabited by different types of organisms. A detailed review of publicly available MELiSSA literature from 1989 to 2022 revealed that no existing stoichiometric model met the study’s requirements. Therefore, a new stoichiometric model was developed to describe the cycling of the elements C, H, O, and N through all five MELiSSA compartments and one auxiliary compartment. A compact set of chemical equations with fixed coefficients was established for this purpose. A spreadsheet model simulates the flow of all relevant compounds for a crew of six. By balancing the dimensions of the different compartments, a high degree of closure is attained at steady state, with 12 out of 14 compounds exhibiting zero loss, and oxygen and CO2 displaying only minor losses between iterations. This is the first stoichiometric model of a MELiSSA-inspired BLSS that describes a continuous provision of 100% of the food and oxygen needs of the crew. The stoichiometry serves as the foundation of an agent-based model of the MELiSSA loop, as part of the Evolving Asteroid Starships (E|A|S) research project.

The main purpose of the research was to examine the processing possibilities of a low-grade high Ca fly ash (FA) to increase its future utilisation potential. Size separation via sieving and mechanical activation with the use of a planetary ball mill was examined to compare the results and complement the application of the various mechanical processes. Based on the preliminary chemical analysis, the composition of the FA below and above 32 µm showed significant variations, thus, the

In the work, the possibility of using microturbine plants to cover auxiliary needs in the electric and thermal energy of complexes for the processing of municipal solid waste, as well as in hydrogen production plants when oxidizing powdered aluminum with water. There were proposed basic thermal diagrams of power units. There were given justification for the choice of wet-steam microturbines, which provide a higher ratio between thermal and electric power, as well as the possibility of their separate regulation in comparison with gas turbine and gas piston units. There were analyzed the working process of a single-stage two-stream active centripetal steam microturbine with an electric power of 50 kW (600 kW - thermal), which was developed, manufactured and tested, both at idle and under load as part of energy technology complexes for the disposal of municipal and agricultural solid waste. Tests showed a reduced blade efficiency of the radial microturbine compared to the calculated one. There were carried out analysis of possible causes of discrepancy and measures were developed to achieve the declared characteristics by subsequent samples of turbogenerators. [ABSTRACT FROM AUTHOR]

The improvement of mixers for homogenizing mixtures with heterogeneous components is considered. Step-by-step homogenization of mixtures is modeled, and analytical expressions are derived to describe the geometric profile of the working surface of single- and double-turn helical blades. Theoretical and experimental results permit the development of a patented design for a pilot industrial hybrid recirculating mixer. [ABSTRACT FROM AUTHOR]

In recent years, carbon fibres have been extensively used to strengthen concrete structures. In most cases, the lamination process is carried out using epoxy resin as matrix. In some cases, especially when strengthen structural elements made of weak concrete, it is possible to replace the epoxy resin with an inorganic, cement matrix, while at the same time maintaining a sufficient efficiency of strengthen understood as the percentage increase in the compressive strength of concrete samples due to the applied reinforcement in relation to the reference concrete. In these studies, elements of carbon fibres mats that are reinforced with a cement matrix were used as the starting product for fibre recovery. The laminate, which was used to reinforce concrete elements, was detached from the concrete surface and subjected to processing in order to obtain clean carbon fibre scraps without cement matrix. Then, the obtained carbon material, in shaped form, was used to strengthen self-compacting, high performance, fibre reinforced concrete (SCHPFRC). For comparative purposes, this concrete was also strengthened by carbon fibre mats (with one and three layers of CFRP). Each samples were tested in uniaxial compression test. The compressive strength of concrete reinforced with 1 and 3 layers of CFRP was higher by 37.9 and 96.3%, respectively, compared to the reference concrete. On the other hand, the compressive strength of concrete reinforced with 1 and 3 layers of carbon fibre scrapswas higher by 11.8 and 40.1%, respectively. Regardless of the reinforcement technique used, the composite elements showed a higher deformability limit in comparison plain concrete. The obtained results showed that it is possible to reuse carbon fibre to strengthen structural elements made of SCHPFRC effectively, using simple processing methods. [ABSTRACT FROM AUTHOR]

The relevance. The waste of Baikal Pulp and Paper Mill causes a real danger of a social and environmental disaster for Lake Baikal and the entire Southern Baikal region, therefore, the problem of developing integrated solutions for dumping the accumulation of lignin-containing waste is especially acute. One of the promising areas for processing this type of waste is the use of natural processes, for example, freezing in winter, temperature detection or self-overgrowth of the occurrence of natural succession. The main aim of the research is to develop an environmentally friendly technology for processing colloidal lignin-containing waste from the pulp and paper industry. Methods: pilot tests at the Solzan industrial site of Baikal Pulp and Paper Mill for freezing lignin-containing wastes and obtaining soils from them by mixing with additives; performing quantitative chemical analysis using the methods of atomic absorption and atomic emission spectrometry, high performance liquid chromatography, toxicological analysis. Results. Pilot tests have shown that after freezing, the colloidal structure of lignin-containing sediments is destroyed with a decrease in volume up to 40 %, humidity up to 60 %, and also with a decrease in toxicity – from the third (moderately hazardous) to the fourth (low hazardous) and fifth class (practically non-hazardous) of hazard of the waste depending on its composition. After freezing, the resulting sludge with the introduction of various additives (CHP ash, sewage treatment plant sludge) can be used as soil ground and fertilizers for reclamation of disturbed lands and crops. Thus, an environmentally friendly technology was developed for processing waste from the pulp and paper industry to obtain soil ground, which is low-energy and does not contain expensive imported equipment.

Aloe vera plant is known worldwide for its medicinal properties and application in gel-based products such as shampoo, soap, and sunscreen. However, the demand for these gel-based products has led to a surplus production of Aloe vera processing waste. An Aloe vera gel processing facility could generate up to 4000 kg of Aloe vera waste per month. Currently the Aloe vera waste is being disposed to the landfill or used as fertilizer. A sustainable management system for the Aloe vera processing waste should be considered, due to the negative societal and environmental impacts of the currents waste disposal methods. Therefore, this review focuses on various approaches that can be used to valorize Aloe vera waste into value-added products, such as animal and aquaculture feeds, biosorbents, biofuel and natural polymers. Researchers have reported Aloe vera waste for environmental applications biosorbents used for wastewater treatment of various pollutants. Several studies have also reported on the valorization of Aloe vera waste for production of biofuels such as bioethanol, mixed alcohol fuels, biogas and syngas. Aloe vera waste could also be valorized through isolation and synthesis of natural polymers for application in wound dressing, tissue engineering and drug delivery systems. Aloe vera waste valorization was also reviewed through extraction of value-added bioactive compounds such as aloe-emodin, aloin and aloeresin. These value-added bioactive compounds have various applications in the cosmetics (non-steroidal anti-inflammatory, tyrosinase inhibitors) and pharmaceutical (anticancer agent and COVID 19 inhibitors) industry. [ABSTRACT FROM AUTHOR]

A concept was proposed for integrated catalytic processing of organochlorine waste using self-organizing nickel-based catalysts. The process of carbon erosion of a bulk Ni–Cr alloy to form dispersed particles catalyzing the growth of carbon nanofibers was studied using 1,2-dichloroethane as an example. This approach was found to be universal and applicable to the processing of multicomponent mixtures of organochlorine compounds, including polyvinyl chloride production waste. The potential of using the carbon nanomaterial obtained by the waste processing for the production of polymer composites was discussed. [ABSTRACT FROM AUTHOR]

Refuse-derived fuel (RDF) can be produced from combustible materials contained in municipal waste. This article investigates energy and material flow of waste in different scenarios for production of RDF from bulky waste, separately collected waste, and mixed municipal solid waste (MSW). We compare the proportion of energy consumption in transportation, handling waste, and processing using data from the waste collection company in South Poland. The findings show the components of the reverse supply chain consuming the highest value of energy. A model of material and energy flow has taken into consideration collection of waste and transportation by two categories of waste collection vehicles: light commercial vehicles and garbage trucks. The shipping of RDF from pre-treatment facilities uses tipper semi-trailers and walking floor trailers. The findings of the study show production of RDF from municipal solid waste consumes almost 10% of energy potential in RDF. Less energy is required for the production of RDF from bulky waste (2.2–4.8%) or separately collected waste (1.7–4.1%) depending on the efficiency of collection and selected vehicles. Transportation consumes the greatest portion of energy. For mixed municipal solid waste (MSW), it can reach 79%; for separated collection waste, 90%; and for bulky waste, up to 92% of the total energy consumed. Comparing emissions for two categories of the collection vehicles, no significant difference was found for the bulky waste collections. For mixed MSW and separately collected waste, the emissions are higher for garbage trucks. A recommendation for practitioners is optimization of routing to achieve a higher collection rate at a minimized route length. For transportation of RDF to WtE plants, vehicles with higher loading capacity are essential. [ABSTRACT FROM AUTHOR]

In Russia, the total amount of agricultural waste reaches 630-650 million tons annually. This waste, on the one hand, creates serious environmental and sanitary problems, almost half of this waste is manure (approximately 300 million tons), on the other hand, it is valuable raw material for the production of organic fertilizers. The state of the problem of processing agricultural waste as a newly emerging industry for the disposal of such waste in conjunction with the development of the industry for the production of organic products and the market for organic fertilizers is considered and solutions are proposed. Information on the legislative support of the organic farming industry and the production of organic fertilizers is presented. Specific measures are proposed to stimulate the development of the industry of processing waste into organic fertilizers and the industry of producing organic products. The growth of the Russian market for organic products since 2010 has been approximately 10% per year, in 2015-2016 the growth was approximately 4%, in 2017-2019 the situation with the development of organic products has recovered, and now there is a steady growth of 8-10% per year. Special attention is paid to priority technologies for processing waste into organic fertilizers, designs based on turbo-vortex shredding and drying machines for the production of highly concentrated dry finely dispersed organic fertilizers and designs based on aeration reactors (biotrenches) for use in large-scale production are considered. [ABSTRACT FROM AUTHOR]

Hydrated γ-, γ'-, θ-, and κ-Al2O3 powders were precipitated with nitric acid, HNO3, from Na[Al(OH)4] alkaline solutions at pH = 5.0–5.5. Waste materials from α-B12Al and B12(C–Al–C) laboratory production were used. The precipitates were rinsed and dried at 420 → 570 K (Sspecific BET = 213 m2 ⋅ g–1, dCSD crystallites ≈ 10 nm, and dSEM agglomerates ≈ 200 nm). The samples were characterized by X-ray diffraction, X-ray diffractometry in the coherent scattering domain (CSD), fluorescence analysis, scanning electron microscopy (SEM), chemical elemental and phase analyses, and thermal desorption of nitrogen calculated by the BET method (Sspecific BET) for interpreting surface measurements of nonporous bodies. The concentrations of gas-forming elements (hydrogen, nitrogen, oxygen, and carbon) were determined by reductive and oxidative extraction in helium and oxygen flow, gas chromatography, and coulometry. The multiphase γ-, γ'-, θ-, and κ-Al2O3 samples treated at 1370–1470 K in air exhibited an α-Al2O3 structure. According to X-ray diffraction in hkl012 CSD, the α-Al2O3 crystallites had dCSD ≈ 48 nm. Based on SEM analysis, the sizes of the α-Al2O3 powder agglomerates did not exceed dSEM = 200–300 nm. The specific surface area of the powder, Sspecific BET, determined by thermal desorption of nitrogen calculated with the BET method, was equal to 8.6 m2 ⋅ g–1. The weight content of α-Al2O3 was 99.69%, while SiO2 impurities accounted to 0.31%, according to X-ray fluorescence analysis. The crystallites, as components of the alkaline γ-, γ'-, θ-, κ-Al2O3, and α-Al2O3 powder agglomerates, showed a lamellar shape. The thickness of the lamellas was close to the calculated dCSD values for crystallites. The submicron γ-, γ'-, θ-, and κ-Al2O3 particles had a 'sandglass' shape, determined by the dynamics of precipitating flat crystallites of the Al(OH)3 solid phase (nanosized thickness) as pH decreased. The α-Al2O3 agglomerates consisted of fused local particles connected by bridges. [ABSTRACT FROM AUTHOR]

Resource recovery and better use of food processing wastes are topics of significant attention. Fruit wastes in particular are perishable yet contain a wealth of unrealized advantages. This study presents the 3D printability of banana peel (BP) powder with the addition of guar gum (GG). The particle characteristics of BP powder were analyzed. The microscopic morphology of the BP powder was found to be erratic and clumped. The printability of extruded material supply was optimized after the characterization of BP and BP + GG material supplies. When 6 bar pressure was used and the motor speed was 150 rpm, it was found that the BP + GG material supply could be printed utilizing a 1.2 mm nozzle diameter. Printing speed and printing rate was optimal at 500 mm/min and 0.186 ± 0.002 g/min, respectively. A nozzle height of 0.8 mm was found to be optimal for printing. Thus, non-printable BP was made printable and the concept can be applied to the development of unique and customized food packaging casings. The results of this study shed light on how various agri-food wastes can be used to create biodegradable 3D-printed structures.

High temperature thermal plasma gasification can treat non-homogeneous waste at increased conversion efficiency, compared to conventional gasification. A novel nitrogen plasma technology demonstration system is presented. The system can convert 20 kg/h of biomass to synthesis gas and is constructed inside a shipping container, which makes it mobile and suitable for application in remote rural areas of developing countries. An Aspen Plus model of the plasma gasification reactor was developed to enable energy and exergy analysis. The model gave good predictions of the real synthesis gas composition obtained during experimental runs. Simple gas and steam power cycles were also modelled to assess the feasibility of the system producing its own power. Based on typical composition of wood, it was found that the plasma torch power requirement is 20.7 kW. This amount of power can be generated using an open gas turbine cycle with compressor pressure ratio of 5 and turbine inlet temperature of 1007 °C. For a combined cycle case, using steam at 8 bar and 400 °C in a steam cycle, 14.6 kW of excess power becomes available. Alternatively, 68 kg/h of steam can be delivered, in addition to satisfying the torch requirement. • Plasma gasification can treat non-homogeneous waste at high conversion efficiency. • Plasma gasification requires significant power for the plasma torch. • A containerized nitrogen plasma system for small scale waste processing is presented. • The plasma torch power requirement can be satisfied by converting the syngas to power. • Exergy analysis identified non-avoidable and avoidable losses for future improvement. [ABSTRACT FROM AUTHOR]

Sustainable management of coal waste is one of the major environmental concerns for coal mining, whether active or legacy, worldwide. Coal dump deposits demand a large physical area or footprint for disposal of solid waste, change the topography, and generate both pyritic dust and acid rock drainage (ARD) where pyritic coal waste is deposited. The beneficiation of dump deposits or, preferably, of coal waste prior to its dumping can reduce or even eliminate the liabilities related to coal waste management. In this work, dense medium separation studies of coal discards, using heavy liquids, resulted in three pooled fractions from typical South African coal waste discards from the Mpumalanga region for future use: (a) a fraction of low density with increased calorific value; (b) a fraction of intermediate density, rich in ash and acid neutralizing minerals and lower in sulfur; and (c) a fraction of high density, rich in sulfidic minerals including pyrite. The fractions were characterized using particle size analysis, sink-float studies, static tests to predict ARD potential, proximateand ultimate analysis, and gross calorific value. The results showed that approximately 70% of this discard coal is composed of a material of sufficient quality for energy generation in conventional power stations. A pyrite-rich concentrate made up 2% of the total discard mass; comprising more than 45% of the sulfidic mineral present in the feed and displaying no acid neutralizing capacity (ANC). The remaining discard fraction, with intermediate density, presented potential to be used for several ends including soil fabrication, co-disposal or as aggregate material in civil engineering; additional testing to ensure applicability for the selected re-purposing option should be chosen based on proposed use. [ABSTRACT FROM AUTHOR]

The article deals with a system view of logistic processes within the system of waste collection and treatment in the conditions of the upcoming legislation. The ambition of the authors is to achieve a system that is universally applicable within circular logistics. Such a system is based on existing mostly autonomous systems with the aim of defining a multipurposed and optimized system where individual companies or associations of companies can act as individual subjects in the logistics chain. The authors' approach is based on a system of common defined interfaces in both the handling and transport processes as well as in their information support processes, so that they can be used in the planning of sustainable logistics systems easily. [ABSTRACT FROM AUTHOR]

The influence of the reaction medium (steam) and the amount supplied to the reactor (~200, 400, or 600 mL) on the yield of the basic gas components (CO, CO2, H2, and CH4) in microwave pyrolysis of sawdust is investigated. The dependence of the mean and maximum gas concentrations on the volume of steam supplied to the chamber of the microwave generator is determined. Trends in the gas concentrations over time are identified. The onset and duration of gas emission are established with variation in the volume of steam supplied to the reactor. The optimal supply of reaction medium to the chamber is determined, such that biomass pyrolysis is intensified and the gas yield is a maximum. If excessive steam is supplied to the chamber, the yield and composition of the producer gas become worse. [ABSTRACT FROM AUTHOR]

The review article is concerned with the modern state, analysis of characteristics, properties, significance, and prospects of the slags’ application, which are wastes of ferrous and non-ferrous metallurgy. The material considers the structure of steelmaking slags, characteristics of steel slags, separation of slags by composition, as well as the world and Kazakhstan experiences of processing them, using environmental safety assessment. The article reviews and studies the methods of slag application in road construction, agriculture, casting technologies, manufacture of Portland cement, clay bricks, green concrete, etc. The article summarizes the practical experience of many scientists’ research in the fields of metallurgical slag applications. The scientific novelty consists in the study of both the world and Kazakhstan experiences in the using metallurgical production slags based on practical data of researchers around the world with the identification of positive and negative properties of various slags under certain conditions. This topic will be of interest of scientists and researchers in the field of metallurgy and materials science. As found based on the obtained data, the extraction of metal from slag significantly reduces the cost; slag is recyclable after recovery of useful metals from it; reduction of slag dumps makes it possible to improve the ecological situation, as well as to free valuable land areas. The issues of identifying the peculiarities of mining and metallurgical industries’ development and fundamentally new directions’ elaboration, as well as unconventional ways of existing production technologies’ improvement require further study.

As part of the work, the chemical interaction of finely ground glass (~1 μm), calcium oxide, and water was studied. It is shown that an increase in the fineness of grinding makes it possible to abandon autoclave hardening in the production of products on a hydrosilicate binder. The study of chemical interaction was carried out by calculating the thermodynamic equilibrium and was also confirmed by XRD analysis. DTA analysis showed that an increase in the treatment temperature leads to an increase in the proportion of the reacted phase at the first stage. Subsequently, phase formation is associated with the presence of CaO. The carrier of strength characteristics is the CaO×2SiO2×2H2O phase. The selection and optimization of the composition make it possible to obtain a high-strength glass concrete material with a strength of about 110 MPa. The micrographs of the obtained samples correspond to classical hydrosilicate systems.

The treatment of wastewater is a necessary and legally required reality, which has a direct impact on the benefit of water quality, by avoiding its environmental and landscape deterioration. The country has been installing different urban and industrial liquid waste treatment systems to deal with the degradation of marine, coastal, river and urban environmental systems, caused by the direct discharge of wastewater into the environment. Currently there are several technologies that are applied, depending mainly on the volumes of wastewater to be treated. Among the installed technologies, there are the biodiscs, which are installations of discs with a surface covered with biomass under aerobic conditions that, continuously, consume the organic matter present in the influent wastewater and the lamellar settlers, which have the function of separating the semi-heavy and heavy elements in suspension, which contain wastewater. In the present work, the dynamic behavior patterns of these two technologies installed in a wastewater treatment plant with the use of radiotracers are determined. [ABSTRACT FROM AUTHOR]

A system for the production of activated carbon is considered. The thermal deformation of its components in operation is of interest. A frame design is developed, taking account of the thermal deformation. The strength of the frame is calculated. [ABSTRACT FROM AUTHOR]

This paper reports the results of studying the application of a ferritization method for the integrated purification of used etching solutions. A feature of this work is the use of energy-saving activation of the process by alternating magnetic fields. Its advantages are shown in comparison with traditional thermal activation. The influence of magnetic induction amplitude and key technological parameters of ferritization on the quality of cleaning an etching solution has been studied. The qualitative and quantitative composition of sediments obtained after the ferritization of etching solutions was investigated. Used etching solutions are large-tonnage waste of industrial enterprises. They contain harmful pollutants that have a detrimental effect on the environment. It is promising to treat these solutions in order to obtain valuable commodity products. It is established that with an optimal value of magnetic induction amplitude of 0.1 Tl, the degree of extraction of iron ions from the solution reaches a value of 99.99 %. The best values for the main technological parameters of the process have been determined: the concentration of iron ions in the reaction mixture is 6.6 g/dm³; pH, 11.5; the duration of ferritization is 15 min. The residual concentration of iron ions in purified solutions does not exceed 0.3 mg/dm³. Thus, according to the norms of current standards, they can be reused in production. Comparative analysis indicates the advantages of electromagnetic activation of the reaction mixture. The phases of magnetite Fe3O4 and iron monohydrate δ ‒ FeOОН were detected by the method of X-ray phase analysis in ferritization sediments. It is established that with an amplitude of 0.1 Tl, the sediment contains only magnetite. The study’s results indicate the possibility of further use of sediments for the manufacture of important ferromagnetic substances. The application of the improved ferritization process in production will achieve less energy consumption compared to well-known processing technologies [ABSTRACT FROM AUTHOR]

An increasing number of recycling programs worldwide now use single-use high-density polyethylene (HDPE) plastic bags in conjunction with recycling bins for the storage and collection of recyclable waste. Recycling bags may increase recycling yield and lower street litter; however, they also come with potentially large environmental and economic costs, including the increased use of plastics. To assess the scale of recycling bag use, we conducted a review of municipal management policies and by-laws across Ontario, the birthplace of modern blue box programs. Over 40% of the municipalities we investigated, collectively representing more than 7 million residents, allow the collection of recycling in bags. Subsequently, we conducted a follow-up study to estimate the number of recycling bags actually used by residents, an important metric for environmental managers, in a medium-sized Ontario city that collects recyclables in both bags and bins. Across three collection dates, 9.0 ± 1.3% of households used recycling bags, with a mean of 1.65 bags per house (mean households sampled = 1540). We estimate that approximately 160 households could use over 10,000 recycling bags per year (∼380 kg of plastic). Spatial analysis on the distribution of recycling bags showed some evidence of clustering among nearby neighbours (i.e. social influence); however, these results were inconsistent and highly variable across sampling dates. Our study provides a valuable policy overview and critical baseline data for waste managers weighing the benefits (e.g., litter reduction) and drawbacks (e.g., debagging costs and plastic waste) of recycling bags for the collection of recyclable material.

Municipal solid waste (MSW) consists of the waste obtained from various sources like households, industries, municipalities and other commercial areas. Common landfill and incineration strategies are insufficient to process the waste generated on daily basis. Municipal solid waste contains significant amounts of organic carbon (50–60%) that has great potential for the production of fuels and value‐added products. This review discusses the composition of the organic fraction of municipal solid waste (OFMSW) and waste processing strategies that enable organic carbon recovery compared with conventional methods. Changes in the composition of MSW worldwide and the factors influencing it in various regions are discussed in this study. The processing of diverse OFMSW through thermochemical methods such as incineration, gasification, pyrolysis, torrefaction and hydrothermal carbonization is discussed here with the results of densification or gasification of the organic carbon, enabling its chemical transformation. Additionally, the combined methods, where OFMSW is pre‐treated followed by enzymatic hydrolysis for the conversion of OFMSW to monomeric sugars have also been described. Globally, to ensure sustainable solid waste management and efficient carbon recycling, combined methodologies seem more appropriate. The study also attempts to list the different attempts across the globe that highlight this concept of the transformation of waste into materials and chemicals, improving its commercial value. The commercial success of such OFMSW processing attempts can provide momentum for establishing sustainable treatment technologies and reaping profits, laying the groundwork for a strong and complete carbon‐recycling environment and circular carbon‐based economy. © 2022 Society of Chemical Industry and John Wiley & Sons, Ltd [ABSTRACT FROM AUTHOR]