Minimize Waste Generation Research Articles

Toward Zero Waste: Sustainable Practices in Waste Management at ETUT

The paper discusses Oguz Han Engineering and Technology University of Turkmenistan's (ETUT) waste management initiatives, particularly its Zero Waste Program aimed at minimizing waste generation and promoting sustainability across campus. Strategies include educational campaigns, eco-friendly purchasing, and collaboration with vendors for waste reduction, reuse, and recycling. ETUT employs structured waste categorization, centralized repositories for reusable items, and a recycling plant with advanced sorting machinery. Innovative methods like paper recycling and composting are used, along with exploring plastic repurposing into fibers and fuel. Organic waste management includes composting, notably reducing landfill waste. Inorganic waste reduction involves paper recycling, plastic conversion, and electronic repair and donation. The program emphasizes waste reduction through recycling and reuse, including upcycling workshops. Hazardous waste from laboratories is managed with local authorities for safe disposal, while relevant associations for environmental safety oversee sewage disposal. These strategies highlight ETUT's commitment to sustainability, positioning it as a regional leader in responsible waste management.

Artificial Intelligence in Logistics Optimization with Sustainable Criteria: A Review

In recent years, the integration of artificial intelligence (AI) into logistics optimization has gained significant attention, particularly concerning sustainability criteria. This article provides an overview of the diverse AI models and algorithms employed in logistics optimization, with a focus on sustainable practices. The discussion covers several techniques, including generative models, machine learning methods, metaheuristic algorithms, and their synergistic combinations with traditional optimization and simulation methods. By employing AI capabilities, logistics stakeholders can enhance decision-making processes, optimize resource utilization, and minimize environmental impacts. Moreover, this paper identifies and analyzes prominent challenges within sustainable logistics, such as reducing carbon emissions, minimizing waste generation, and optimizing transportation routes while considering ecological factors. Furthermore, the paper explores emerging trends in AI-driven logistics optimization, such as the integration of real-time data analytics, blockchain technology, and autonomous systems, which hold immense potential for enhancing efficiency and sustainability. Finally, the paper outlines future research directions, emphasizing the need for further exploration of hybrid AI approaches, robust optimization frameworks, and scalable solutions that accommodate dynamic and uncertain logistics environments.

A thorough overview of the literature on waste recycling in the circular economy: current practices and future perspectives.

To develop a circular economy (CE) and protect the environment, waste recycling (WR) is crucial. This study examines WR research conducted over the past two decades to identify the most significant advancements and promising areas for future research. The following challenges were handled through text mining, content, and bibliometrics analysis: How has CE influenced the evolution of WR research? What are the CE's most important WR research trends and themes? What directions could future research on WR take regarding the CE transition? Using 1118 articles from the Scopus database journal, bibliometric networks were made and analyzed. Hence, five critical CE-related problems needing further research were recognized: waste recycling is the first cluster, followed by technology, the CE transformation, plastic waste, and waste management (WM). Examining WM and inclusive waste reduction practices and their distinct highlight patterns may impact future research fields and serve as a transitional tool to CE (which aims to minimize waste generation). Forthcoming research targets contain waste reduction and incorporation of WR into the CE framework.

Circular–Sustainable–Reliable Waste Management System Design: A Possibilistic Multi-Objective Mixed-Integer Linear Programming Model

Waste management involves the systematic collection, transportation, processing, and treatment of waste materials generated by human activities. It entails a variety of strategies and technologies to diminish environmental impacts, protect public health, and conserve resources. Consequently, providing an effective and comprehensive optimization approach plays a critical role in minimizing waste generation, maximizing recycling and reuse, and safely disposing of waste. This work develops a novel Possibilistic Multi-Objective Mixed-Integer Linear Programming (PMOMILP) model in order to formulate the problem and design a circular–sustainable–reliable waste management network, under uncertainty. The possibility of recycling and recovery are considered across incineration and disposal processes to address the main circular-economy principles. The objectives are to address sustainable development throughout minimizing the total cost, minimizing the environmental impact, and maximizing the reliability of the Waste Management System (WMS). The Lp-metric technique is then implemented into the model to tackle the multi-objectiveness. Several benchmarks are adapted from the literature in order to validate the efficacy of the proposed methodology, and are treated by CPLEX solver/GAMS software in less than 174.70 s, on average. Moreover, a set of sensitivity analyses is performed to appraise different scenarios and explore utilitarian managerial implications and decision aids. It is demonstrated that the configured WMS network is highly sensitive to the specific time period wherein the WMS does not fail.

Rethinking Nanoparticle Synthesis: A Sustainable Approach vs. Traditional Methods.

This review portrays a comparison between green protocols and conventional nanoparticle (NP) synthesis strategies, highlighting each method's advantages and limitations. Various top-down and bottom-up methods in NP synthesis are described in detail. The green chemistry principles are emphasized for designing safe processes for nanomaterial synthesis. Among the green biogenic sources plant extracts, vitamins, enzymes, polysaccharides, fungi (Molds and mushrooms), bacteria, yeast, algae, and lichens are discussed. Limitations in the reproducibility of green protocols in terms of availability of raw material, variation in synthetic protocol, and selection of material due to geographical differences are elaborated. Finally, a conclusion is drawn utilizing green chemical principles, & a circular economy strategy to minimize waste generation, offering a promising framework for the synthesis of NPs emphasizing sustainability.

A Comprehensive Review of Engineering Strategies for Environmental Sustainability in Sustainable Waste Management

Waste management and environmental sustainability are intricately linked aspects crucial for maintaining ecological balance and human well-being. This study synthesizes research findings and scholarly insights to underscore the significance of effective waste management practices in achieving environmental sustainability goals. It examines waste treatment approaches, including recycling, waste-to-energy systems, and waste reduction strategies, highlighting their role in mitigating environmental impact. Additionally, the study explores the environmental consequences of inadequate waste management, emphasizing the urgent need for holistic solutions to address water, soil, and air pollution. Engineering solutions for sustainable waste management, such as the 3R principle (Reduce, Reuse, Recycle), thermal treatment methods, and landfill management, are discussed as essential components of a comprehensive strategy. By integrating these approaches, policymakers, industries, and communities can minimize waste generation, conserve resources, and safeguard the environment for current and future generations. Challenges like regulatory barriers, lack of awareness, and inadequate infrastructure pose obstacles to sustainable waste management practices. Thus, a collaborative effort involving governments, businesses, and civil society is crucial to implementing effective waste management policies and initiatives. Through concerted action, we can transition to a circular economy model that promotes resource efficiency, environmental protection, and human well-being on a global scale.

Synthesis of uniform spherical silver powder without dispersants in a confined impinging-jet reactor

Sliver powder is the most common and extensively utilized precious metal powder in electronics, primarily for electronic paste. Herein, micron-sized spherical silver powder was synthesized via a liquid phase reduction method employing silver nitrate as the source of silver and ascorbic acid as the reducing agent in a confined impinging jet reactor (CIJR). The impact of the molar ratio between silver nitrate and ascorbic acid, the flow rate, and the temperature on the particle size of silver powder was investigated. The optimal process conditions for silver powder are as follows: maintain a molar ratio of 1:1 and control the feeding rate at 10 ml/min while operating at 50 ° C. The confined impinging jet reactor offers enhanced control over reaction conditions during the synthesis of silver powder, surpassing the capabilities of traditional batch reactors. The aforementioned optimized methodology was employed to successfully synthesize uniform and spherical silver powder (with an aspect ratio approaching 1) in the low Reynolds number jet, resulting in an average particle size of d50 = 0.83 μm and a standard deviation of 0.07, without the addition of dispersant. The synthesis method presented here improves the performance of silver powder, simplifies the production process, reduces energy consumption, and minimizes waste generation. These advances yield significant environmental and economic benefits. In the future, with the continuous development and optimization of microreactor technology, this synthesis method is anticipated to play a more prominent role in the commercial-scale production and application of micrometer-sized silver powder.

Establishment of circular economy by utilising textile industry waste as an adsorbent for textile dye removal

This study explored the use of waste from the textile industry (silkworm byproducts) as a promising raw feedstock for the production of carbon-based adsorbents (biochar). The silk excreta biochar generated at 600 and 700 °C (referred to as SEB-600 and SEB-700, respectively) were evaluated in terms of their efficacy in adsorbing cationic (methylene blue) and anionic (Congo red) textile dyes. Although the functional groups on the surfaces of SEB-600 and SEB-700 were not significantly different, the specific surface area of SEB-700 was greater than that of SEB-600. The dye adsorption capacity of SEB-700 was higher than that of SEB-600. The adsorption of methylene blue and Congo red on SEB-700 followed Freundlich isotherms (R2 ≥ 0.963) and pseudo-second-order kinetics (R2 = 0.999), indicating chemisorption with multilayer characteristics. The mechanism for the adsorption of methylene blue on SEB-700 may involve interactions with the negatively charged functional groups on the surface and the mesopores of SEB-700. For the adsorption of Congo red, the mesopores in the biochar and the electrostatic interaction between biochar (positively charged because of the dye solution pH < pHzpc) and the anionic dye could affect adsorption. The maximum adsorption capacities of SEB-700 for methylene blue and Congo red were determined to be 168.23 and 185.32 mg g−1, respectively. Utilising the waste generated from the textile industry to remove pollutants will build a sustainable loop in the industry by minimising waste generation and pollutant emissions.

The circular bioeconomy of the olive oil industry: Deterministic and probabilistic profitability of olive mill by-product gasification

In the novel paradigm of the circular economy the value of products, materials, and resources is retained in the economy for as long as possible, thereby minimizing waste generation. In this context, the olive oil producing countries are presented with a new opportunity that lies in the large amount of by-products generated by the olive oil industry, in particular olive pomace. Among the existing options for valorizing it, gasification is a technically proven and economically viable process, especially for moderately high energy prices. This research aims to analyze the profitability of olive pomace gasification, identifying the main uncertainty factors that determine said profitability. To that end, sensitivity analyses and probabilistic scenario analyses using the Monte Carlo method are conducted for the first time in this research context. The results show a positive profit margin of €19.27 per ton of milled olives, a Net Present Value (NPV) of €453,067, and an Internal Rate of Return (IRR) of 9.7 %. The sensitivity analysis indicates that the electricity price is the main determinant of profitability, while other factors, such as the biomass price or the sale of by-products (biochar), are less important. The Monte Carlo analysis reveals the uncertainty involved in these types of projects, showing that the probability of the investment being profitable (NPV>0) is only 25.1 %. The assessment evidences that this kind of projects presents high capital needs and strongly uncertain profitability, recommending the implementation of public and private green finance instruments to overcome high-capital barriers and de-risk these investments.

Green and sustainable fabrication of DES-pretreated high-strength densified wood

Wood is a sustainable, benign, and high-performing green structural material readily available in nature that can be used to replace structural materials. However, insufficient mechanical performance (compared to metals and plastic), moisture sensitivity, and susceptibility to microorganism attack make it challenging to use wood as it is for advanced engineering applications. We here present an efficient approach to fabricating densified wood with minimal time and waste generation, demonstrating high mechanical strength, and decreased water penetration on the surface. Wood slabs were treated with deep eutectic solvents (DESs) to solubilize the lignin, followed by in-situ regeneration of dissolved lignin in the wood. Then, the slabs were densified with heat and pressure, turning the wood into a functionalized densified material. Lignin regeneration and morphological changes were observed via two-photon microscopy and Scanning Electron Microscopy (SEM), respectively. The final product is less susceptible to water absorption on the surface and has enhanced flexural strength (> 50% higher), surface hardness (100% increased), and minimal set recovery compared to natural wood. The improved mechanical performance is due to regenerated lignin which acts as a glue and fills spaces present within the interconnected cellulose network inside the wood, forming a highly dense composite during densification. Such enhancement in the properties of DES-densified wood composite makes it a favorable candidate for advanced structural and engineering applications.

Green and Enantioselective Synthesis via Cascade Biotransformations: From Simple Racemic Substrates to High-Value Chiral Chemicals.

Asymmetric synthesis of chiral chemicals in high enantiomeric excess (ee) is pivotal to the pharmaceutical industry, but classic chemistry usually requires multi-step reactions, harsh conditions, and expensive chiral ligands, and sometimes suffers from unsatisfactory enantioselectivity. Enzymatic catalysis is a much greener and more enantioselective alternative, and cascade biotransformations with multi-step reactions can be performed in one pot to avoid costly intermediate isolation and minimise waste generation. One of the most attractive applications of enzymatic cascade transformations is to convert easily available simple racemic substrates into valuable functionalised chiral chemicals in high yields and ee. Here, we review the three general strategies to build up such cascade biotransformations, including enantioconvergent reaction, dynamic kinetic resolution, and destruction-and-reinstallation of chirality. Examples of cascade transformations using racemic substrates such as racemic epoxides, alcohols, hydroxy acids, etc. to produce the chiral amino alcohols, hydroxy acids, amines, and amino acids are given. The product concentration, ee, and yield, scalability, and substrate scope of these enzymatic cascades are critically reviewed. To further improve the efficiency and practical applicability of the cascades, enzyme engineering to enhance catalytic activities of the key enzymes using the latest microfluidics-based ultrahigh-throughput screening and artificial intelligence-guided directed evolution could be a useful approach.

The application of chromatographic methods in optimization and the enhancement of the oxidative liquefaction process to wind turbine blade recycling

AbstractThe concept of the circular economy aims to maximise the longevity of raw materials, materials, and final goods while simultaneously minimising waste generation. In order to accomplish this objective, researchers are currently exploring emission-free recycling methods and advancing a novel oxidative liquefaction methodology. This process is employed to efficiently degrade the polymer matrix which we can find among other things in wind turbine blades while also conducting chromatographic investigations of the resulting degraded resins. The conducted experiments included a temperature range spanning from 250 °C to 350 °C. The residence lengths varied from 30 to 90 min, while the pressures ranged from 20 to 40 bars. Additionally, the waste-to-liquid ratios were within the range of 5–25%, and the oxidant concentrations were between 15 and 45% by weight. The study’s results will help improve the design of the experiments by focusing on getting the highest concentrations of oxygenated chemical compounds, such as volatile fatty acids, aromatic hydrocarbons, and aromatic carboxylic acids. These compounds are the main chemicals obtained during resin degradation, and identifying the optimal conditions for their production will facilitate the implementation of this process on a larger scale. Graphic abstract

A rapid chemical method for production of xylitol from D-xylose as a renewable feedstock from spent aromatic waste

Xylitol is occurring naturally as a minor constituent in many fruits and vegetables. Commercially, xylitol is produced by chemical methods from D-xylose for application as an alternative sweetener in food and pharmaceutical products. Although biomass-derived xylose can be used as a potential substrate for xylitol production, its prerequisite purification before a catalytic hydrogenation directly impacts the production cost. In addition, the isolation of xylose falls under a routine pretreatment activity during conversion of biomass to platform chemicals. The resulting hydrolysate often exhibits a low concentration of xylose and other monosaccharides. Concentrating the hydrolysate to a desired level for conversion to xylitol under chemical/biological methods increases the expenditure cost. Many times, concentration by heating may cause the degradation of contained sugars in the hydrolysate. Therefore, this study has been carried out to obtain a mixture of C5/6 sugars, predominantly the D-xylose in a solid dry form (∼10 % yield, >98 % purity) directly from acid hydrolysate of spent aromatic waste. Biomass-derived D-xylose was further transformed to xylitol (100 % conversion) by a fast (10 min), efficient, and solvent-free chemical approach using a modified sodium borohydride (NaBH4) catalyst on a wet silica (SiO2) support at RT. All reagents and solvents used in the process were recovered and recycled, leading to the minimal waste generation.

Sustainable Manufacturing Practices in the Hydropower Industry: A review

Abstract Hydropower is a crucial source of renewable energy in the ever-changing world, contributing significantly to global electricity generation. As the world focuses more on sustainability, the manufacturing processes within the hydropower industry have undergone considerable transformations to align with eco-friendly practices. This review explores the landscape of sustainable manufacturing practices implemented in the hydropower sector, examining the various strategies, technologies, and initiatives adopted to minimize environmental impact while enhancing efficiency of the project. The review encompasses the significance of sustainable materials and manufacturing techniques within the context of hydropower, highlighting the industry’s commitment to reducing its carbon footprint. It consists of the utilization of advanced materials and technologies aimed at optimizing the manufacturing processes, enhancing the durability and efficiency of hydropower components, and reducing resource consumption. Also, the review highlights the adoption of life cycle assessment (LCA) methodologies in the development and manufacturing phases of hydropower components. These practices facilitate the evaluation of environmental impacts across the entire life cycle of hydropower projects. Furthermore, the review discusses about the implementation of innovative approaches such as Additive manufacturing and CNC machining process as well as casting methods, streamlining production while minimizing waste generation and energy consumption. It also includes the case study of best practices that are prevalent in the context of sustainable manufacturing Additionally, the review examines the role of regulatory frameworks, standards, and certifications in driving sustainable manufacturing practices within the hydropower industry scenario in the world. It also outlines potential future directions to further enhance sustainability in hydropower manufacturing.

Thermokinetic study of tannery sludge using combustion and pyrolysis process through non-isothermal thermogravimetric analysis

Sludge from the tannery is produced in enormous amount. This work has investigated the thermal analysis behaviour of the tannery sludge by use of the thermogravimetric analysis (TGA). The TGA experiments is carried out in both air and nitrogen environment at the varied heating rates of 5, 10, 20 and 40 °C/min from the temperature range of 30–900 °C. In the assessment of kinetic parameters, the model fitting (Combined kinetics) method was employed. It was investigated that thermal degradation of the tannery sludge sample occurred in three stages. Majorly the conversions were observed in stage II for both in air and nitrogen environment. The activation energy (Ea) value for the combustion is 165.9 kJ/mol while for the pyrolysis the Ea value is obtained as 65.2 kJ/mol from the conversion range between 0.2 and 0.8 which is a promising approximation supported by a strong R2 value of 0.9719 and 0.93 for combustion and pyrolysis respectively. It is estimated from the master plots that six ideal models A1/2, A1/3, A1/4, F3, F4 and D5 were probably in approximation with the linear fitted data for both air and nitrogen. Various thermodynamic parameters which include the ΔH, ΔG and ΔS are also complimented that indicates the formation of activated complex and non-spontaneity of the reaction. The detailed thermokinetic study of the tannery sludge in combustion and pyrolysis offers a novel approach to understanding how this waste material decomposes under different temperature conditions. This holistic perspective contributes valuable insights into waste management practices, environmental impacts, resource recovery, and process optimization within the leather industry. Furthermore, the optimization of leather production processes on a large scale can minimize waste generation and enhance energy efficiency, strengthening the competitiveness and sustainability of the leather industry.

Willingness of Buyers to Buy Wearable Rejected Clothes from Clothing Manufacturers: Model for Fostering Sustainable Apparel Business

The apparel industry in Bangladesh produces rejected garments while manufacturing high-quality exportable garments. This industry faces challenges in managing rejected garments as they contribute to waste generation. The purpose of this study was to explore the current policy of managing rejected garments and look for a more sustainable business model or policy. This research collected opinions and information from 18 different garment manufacturing industries regarding rejected garments and buyers’ and manufacturers’ existing policies for managing the rejected garments. The results of the study show that there is no particular guideline from the buyers for managing rejected garments; consequently, the manufacturers handle these garments in their own way. A novel and more sustainable business model for the clothing business was proposed to align the business with the Sustainable Development Goal 12 (responsible consumption and production). This model urges collaborative efforts between buyers and manufacturers to capture more value from rejected garments and extend their lifecycle. The proposed framework will benefit relevant stakeholders, minimise waste generation and reduce the impact of fast fashion.

АNIMAL AND VEGETAL WASTE GENERATED BY EU MEMBER STATES IN THE PERIOD 2016 – 2020

Waste generation poses a significant challenge in today’s world, prompting ongoing efforts to find effective solutions. While different countries have made varying progress in addressing this issue, environmental protection and the enhancement of food product quality remain key drivers. Notably, the agricultural sector enjoys an advantage: a relatively small proportion of its waste is hazardous. In fact, most of the waste generated is both safe and recyclable. Proper management of processing procedures is crucial to unlock its potential for widespread utilization across diverse economic activities and in various forms. This study aims to track the trends and compare agricultural waste generation in Bulgaria with that of the other EU Member States. It spans the years 2016, 2018, and 2020, analysing waste data by type for each year. Using available Eurostat data, the authors have made their own calculations. The findings underscore the importance of addressing waste management promptly, emphasizing the need to limit and minimize waste generation within the European Union during the specified period.

Halogenation of Alkenes Using Three‐Component Reactions: A Decade of Development

AbstractAlkenes are valuable feedstocks in organic synthesis. One effective method for synthesizing organic halides with functional groups in close proximity involves the direct difunctionalization of alkenes via three‐component reactions. This approach not only reduces the number of steps involved in the synthesis process, but also minimizes waste generation and enables the formation of complex molecules from simple starting materials. In this review, we mainly discuss decade developments (2013‐2023) in two categories: (1) halogenation via three‐membered ring intermediates, involving haliranium, thiiranium,seleniranium, aziridinium and epoxide species; (2) halogenation via a radical pathway. Reactions with I2, BiI3, NaI, Bu4N+[I(O2CAr)2]−, NIS, NBS, NCS, DBH, BsNMeBr, HBr, HCl, KI, NH4I, I2O5, Et3N ⋅ 3HF, Selectfluor, CuI, CuBr, CuCl, LiCl, KBr, NaCl, SOCl2, Py ⋅ 9HF, NFSI, TBSCl et al have been recorded and how the added reagents work will be discussed. We hope this review will do help for future research in this area.

Advancing Circular Economy: Czech perspective

This article provides a comprehensive overview of the transition to a circular economy, focusing on the European Union’s (EU) efforts and the Czech Republic’s stance and actions. It elaborates on the urgent need to shift from a linear economy, which burdens Earth’s resources and leads to substantial waste, to a more sustainable circular economy by 2050. The circular economy paradigm is seen as a fundamental shift in managing waste and resource use towards maintaining the value of products and materials for as long as possible and minimising waste generation. The article outlines the EU’s initiatives, policies, and legislation to foster this transition, emphasising the critical role of member states in implementing specific measures. Several EU policies, like the Green Deal and the New Circular Economy Action Plan, aim to transform the economy from linear to circular, covering various waste streams and sectors. Particular attention is given to the Czech Republic’s position and efforts. It delves into Czech waste legislation, policies related to the circular economy, and the nation’s strategic documents like the State Environmental Policy 2030 and the Strategic Framework of the Circular Economy of the Czech Republic 2040; these aim to improve waste management, enhance material supply security, boost business competitiveness, and reduce fossil fuel consumption. The article also discusses the challenges and public opinion in the Czech Republic regarding environmental protection and the circular economy. Despite progress, factors such as inadequate use of economic instruments and public reluctance to pay more for sustainable products hinder a faster transition. Furthermore, the article reviews specific legal instruments, economic tools, and sectoral legislative acts contributing to circularity in the Czech Republic. In conclusion, while the Czech Republic and the EU have made strides towards a circular economy, the journey is ongoing. The transition promises long-term benefits like self-sufficiency, reduced greenhouse gases, and new job opportunities. The EU’s role is crucial in this transition, as it sets legislative and policy frameworks that guide member states towards circularity. This article reflects the complexities and multifaceted nature of transitioning to a circular economy, highlighting the need for continued efforts, policy alignment, and societal support.

CsCl enrichment during solidification of molten LiCl–KCl–CsCl salt mixture

Metallic alloy fuels from fast reactors will be reprocessed by a non-aqueous electrochemical technique known as electrorefining. Electrorefining of spent metal fuel results in the accumulation of heat generating fission products especially 137Cs in the electrolyte, which is a eutectic salt mixture of 44 wt% LiCl and 56 wt% KCl. The fission products need to be removed from the salt so as to reduce the decay heat load and contamination thereby facilitating reuse of the salt and minimizing waste generation. Melt crystallization technique is a simple separation process being pursued for separation of fission products. This is a single step process which utilizes the difference in solubility of fission products in the solid and liquid phase. Crystallization involves purification of a substance from a liquid mixture by solidification of the desired component. Numerical modeling of separation of CsCl from a LiCl–KCl eutectic mixture by solidification was carried out using ANSYS Fluent (19.2). The enrichment of CsCl during solidification, its distribution in molten salt and segregation time were evaluated. Further, solidification experiments were conducted using the molten salt mixture and the predicted numerical results were validated.