Emerging deep eutectic solvents for food waste valorization to achieve sustainable development goals: Bioactive extractions and food applications.

Food waste, accounting for about one-third of the total global food resources wasted each year, is a substantial challenge to global sustainability, contributing to adverse environmental impacts. The utilization of food waste as a valuable source for bioactive extraction can be facilitated through the application of DES (Deep Eutectic Solvents). Acknowledging the significant need to tackle this issue, the United Nations integrated food waste management into its Sustainable Development Goals, hence, the present review explores the role of DES in bioactive compounds extraction from food waste. Various extraction processes using the DES system are thoroughly studied and the application of bioactive components as antioxidants, antimicrobials, flavourings, nutraceuticals, functional ingredients, additives, and preservatives is investigated. Most importantly, regulatory considerations and safety aspects of DES in food applications are discussed in-depth along with consumer perception and acceptance of DES in the food sector. The key hypothesis of the review is to evaluate emerging DES systems for their efficiency in bioactive extraction technologies and various food applications. Overall, this review provides a comprehensive understanding of utilizing DES for synthesizing valuable food waste-derived bioactive components, offering a sustainable approach to waste management and the development of high-value products.

Assessment and management of construction and demolition waste in tier 2 cities of Karnataka, India: a case study of Hubli-Dharwad and Davanagere.

The present study examines the current practices for managing construction and demolition waste (CDW) in two tier-2 cities of Karnataka state: Hubli-Dharwad and Davanagere. The research highlights the quantification, characterization, and effective management strategies for CDW. CDW dumping sites were identified through field visits conducted across all wards of the cities and recorded using a mobile-based app. At each site, data were collected on the types of vehicles dumping CDW, the frequency of dumping, the volume of waste in the vehicles, and the quantity of CDW removed for reuse. The dumping sites were categorized into large, medium, and small based on the area and volume of waste. In total, 130 unauthorised dumping sites were identified in Hubli-Dharwad and 62 in Davanagere. The study estimated that Hubli-Dharwad generates approximately 607 tonnes per day (TPD) of CDW, while Davanagere produces around 287 TPD. The characterization of CDW revealed that in Hubli-Dharwad, CDW consists of 14.4% concrete, 25.5% brick and mortar, 39.1% soil and aggregates, and 20% other materials. In Davanagere, the composition includes 19% concrete, 29% brick and mortar, 38% soil, and 14% other materials. Based on these findings, the study proposes a system for the collection and transportation of CDW and recommends suitable recycling technologies. While the approach outlined in this paper is well-suited for urban local bodies to assess CDW, the data on CDW reuse and recycling is primarily based on informal practices. This makes accurate quantification challenging and subject to variation over time due to a lack of regulatory oversight. Additionally, the study provides only a snapshot of CDW generation and management at a specific point in time, potentially missing seasonal variations or long-term trends in waste handling.

Marine plastic pollution: A systematic review of management strategies through a macroscope approach.

Alternatives to address the ocean plastic crisis have been a hot topic in scientific literature, although a systemic approach to assess their effectiveness and identify bottlenecks is still lacking. To contribute to discussions on this topic, this study aims to conduct a literature review on current scientific information regarding management strategies for marine plastic pollution. The PRISMA method was used to select the most relevant articles from the Scopus® database, resulting in a sample of 176 articles after applying exclusion criteria for full-text evaluation. Unlike other literature review studies, Odum's Macroscope is used here to develop a model that provides a systemic view of the plastic crisis on a large scale, encompassing various compartments and their interactions. Specifically, eight compartments are identified: industry, consumers, waste collection & management, freshwater systems, fisheries, aquaculture and shipping, marine ecosystems, marine plastic collection and recycling, and life cycle. Each piece of literature reviewed is categorized into one of these compartments and discussed accordingly. The highlights of the results indicate that: (i) waste collection & management and freshwater systems, which are primary pathways for plastic litter reaching the ocean, have been relatively under-investigated compared to other compartments. (ii) Most studies originate from developed countries, raising doubts about the effectiveness of management proposals in underdeveloped countries. (ii) Existing strategies for collecting and recycling marine litter are unlikely to be implemented at a large scale due to operational obstacles, thus offering insufficient mitigation for the plastic crisis. (iv) The development of new biomaterials has proven mostly ineffective and harmful. (v) Alternatives management for microplastic pollution are still in their infancy, resulting in scarce information across all compartments. (vi) No studies focus on the origin of the plastic issue, which lies in the petrochemical industry. From a general perspective, the literature indicates that there is no one-size-fits-all management strategy to the plastic crisis, and the available options are often scattered and disconnected, making a systemic approach essential for studying such a transboundary issue. While efforts exist, stakeholders must act to effectively address the problem, or at least make meaningful progress. The marine plastic crisis operates systemically, analogous to the climate crisis, both stemming from human dependence on fossil fuels. Similar to achieving carbon neutrality, designing a globally sustainable economy should prioritize achieving plastic neutrality as a core component.

Sustainability synergies and trade-offs considering circularity and land availability for bioplastics production in Brazil.

Alongside the concerns of waste management, plastic production represents a future problem for managing greenhouse gas emissions. Advanced recycling and bio-based production are paramount to face this challenge. The sustainability of bio-based polyethylene (bioPE) depends on the feedstock, avoiding stress on natural resources. This work discusses Brazil's potential to meet future global bioPE demand by 2050, using sugarcane as feedstock and considering environmental sustainability for production expansion. From the assessed 35.6 Mha, 3.55 Mha would be exempt from trade-offs related to land use change (dLUC), biodiversity, and water availability. The scenario with the highest circularity efficiency would require 22.2 Mha to meet the global demand, which can be accommodated in areas with positive impacts in carbon stocks, neutral impacts in water availability, and medium impacts on biodiversity. Here, we show that dropping demand is essential to avoid trade-offs and help consolidate bioPE as a sustainable alternative for future net-zero strategies.

Hospital waste management system in Kermanshah: challenges, future and sustainable management with circular economy.

Proper hospital waste management poses important concerns due to the risk capacity of hospital waste to health and the environment. Healthcare management approaches have changed in recent years, motivated by the desire to minimize the environmental impact. The review aims to examine the current HCW and considers the local challenges associated with establishing a circular economy (CE) to improve hospital waste management regarding training along Plan, Do, Check, and Act (PDCA). The study found that mean medical and general waste segregation rates in public hospitals were 50.15 and 49.85, respectively. On average, 3.6 kg of waste was generated per bed per day. Analysis revealed a significant correlation between total waste and infectious waste with the number of occupied beds in the hospital (p < 0.05). Updating national laws by the CE approach is necessary. Our insights into circular hospital waste urge establishing a green management team, new training methods, and continuous supervision. Using PDCA to enhance waste segregation, training, and other aspects of hospital waste management is vital.

Integrated municipal solid waste management using ArcGIS tools: A case of akaki-kality sub-city, addis ababa, ethiopia.

This study aimed to optimize the solid waste collection and transportation system using ArcGIS Network Analyst and location-allocation tools. The generated solid waste was characterized by proximate analysis. The generation rate and composition were determined according to standard methods. The average solid waste generation rates for households, commercial sites, institutions, and recreational places were 0.48 kg/c/day, 15.03 kg/fac/day, 9.32 kg/fac/day, and 22.8 kg/fac/day, respectively. The estimated total generation rate of the sub-city is 207,004.03 kg/day and 712.13 m3/day as discarded base. Composition analysis revealed that food waste is the major component of municipal solid waste, with estimated weight and volume of 134,696.08 kg and 299.46 m3, respectively. Proximate analysis indicated that food and textile wastes have relatively high moisture content and fixed carbon. Candidate pre-collection bin allocations were optimized based on factors such as road network, distribution of solid waste generators, and existing temporary dumping sites, resulting in 1052 potential bin locations. Transfer station allocation was optimized by considering land use-land cover, slope, and geology. Twelve transfer routes and four transport routes were established to efficiently serve the bins and final waste destinations. In conclusion, the study demonstrates that ArcGIS Network Analyst and location-allocation tools can effectively optimize the municipal solid waste collection and transportation system, providing a robust framework for improving waste management efficiency. However, further research is recommended to validate these findings through field application.

Synthesis of nanoporous carbon from Ulva lactuca activated by eggshell for CO2 capture: a novel approach to waste valorization.

Facing the daunting challenge of climate change, driven by escalating greenhouse gas concentrations, our research introduces an innovative solution for CO2 capture. We explore a novel nanoporous carbon derived from Ulva lactuca, activated with eggshell waste, spotlighting waste valorization in mitigating atmospheric CO2. Through a systematic methodology encompassing variable carbonization temperatures (700-900 °C) and nitrogen flow rates (2-4 ml/min), complemented by a suite of characterization techniques, we unveil the synthesis of this pioneering adsorbent. Our study not only presents a novel, sustainable pathway for CO2 capture but also demonstrates superior performance, particularly with the NC800-4 sample, achieving a CO2 capture capacity of 1.40 mmol/g at 30 °C, alongside demonstrating consistent adsorption efficiency over four successive adsorption/desorption cycles. This breakthrough underscores the potential of leveraging waste for environmental remediation, offering a dual solution to waste management and carbon capture, utilization, and storage (CCUS) applications.

Environmental sustainable treatment and disposal technologies for reservoir wastes: a review.

The process of dredging reservoirs serves the purpose of preserving water storage capacity and ensuring the functionality of navigational channels. Additionally, it has the potential to mitigate the presence of pollutants and chemicals that pose risks to both the environment and human well-being. This review article examines the many ways of disposal and treatment of dredged sediment, as well as the ecological and economic advantages associated with these approaches. Algae and reed-based treatment methods have the potential to effectively and economically remediate and sustainably manage dredged sediments. Landfills and ocean dumping are widely utilized methods for the disposal of excavated materials. However, other approaches such as land reclamation, the use of fill material, and the preservation of wetlands can offer cost-effective solutions while also contributing to environmental conservation. The implementation of sediment cleaning, stabilization, and solidification techniques has the potential to effectively mitigate waste and improve the quality of sediment, hence facilitating its reuse. Algae and reed-based treatment systems have been found to effectively mitigate disposal costs and contribute to environmental enhancement. Additionally, the practice of reusing dredged sediments has been recognized as a valuable strategy in promoting a circular economy.

A Disposable Diaper Collection Project in Langa, Cape Town, South Africa: A Pilot Study.

In developing countries, there is currently no established waste management plan that includes resource recovery from used disposable diapers (DDs) apart from incineration and landfilling. In low-income areas with limited storage space, the complex composition and odour of used DDs make it impossible to manage properly if not supported by effective waste management systems. In the absence of effective waste management, DDs are dumped in open spaces, burned or buried. These actions pose threats to the safety and health of humans, animals and the environment. Separation and collection of DDs are critical preliminary steps to landfilling, recycling or beneficiation. In this article, we describe a case study of two pilot collection projects in Langa township in Cape Town, South Africa, to determine whether and how a source-separated collection system can work in low-income, resource-constrained areas. The lessons learned highlighted the following: The eagerness of parents to participate for the benefit of their own and their children's health; the complementarity of the two pilot collection models to serve the needs of the community; the important role non-government organisations play in the implementation of waste management projects; the significance of the possible job creation opportunities and the unintended benefits of enhancing social cohesion. The financial sustainability of these projects needs further exploration.

Unraveling the role of black soldier fly larvae in chicken manure conversion: Facilitating maturation and enhancing humification.

Black soldier fly larvae (BSFL) have garnered considerable attention for their efficacy in mitigating waste management challenges. However, their potential in treating antibiotics contaminated chicken manure remains uncertain. This study investigates the physicochemical properties changes and nutrient dynamics during the composting of contaminated-chicken manure using BSFL. The results indicate that BSFL treatment reduces electrical conductivity (by 6.01-58.09 %), organic matter, and dissolved organic carbon content in chicken manure throughout the composting process, while maintaining a more stable pH value (pH âˆ¼ 6.0-8.0). This is attributed to the consumption of organic matter by BSFL and the subsequent promotion of organic acid formation. Additionally, BSFL treatment improves the degree of aromatization of dissolved organic matter (DOM) in chicken manure and increases the proportions of fulvic acid (up to 48.77 %) and humic acid (maximally 14.27 %) within the DOM. The germination index and pot experiments indicated improved compost maturity and plant growth in BSFL-treated composts. Furthermore, BSFL meal demonstrated high protein and essential fatty acid content, highlighting its potential as a protein supplement in animal feed. This study underscores the efficacy of BSFL in enhancing compost quality and nutrient availability, offering a sustainable solution for waste management and animal feed production.

Valorizing waste activated sludge incineration ash to S-doped Fe2+@Zeolite 4A catalyst for the treatment of emerging contaminants exemplified by sulfamethoxazole.

The global attention towards waste management and valorization has led to significant interest in recovering valuable components from sludge incineration ash (SIA) for the synthesis of functional environmental materials. In this study, the SIA was converted to an S-doped Fe2+-zeolite type catalyst (FZA) for the treatment of emerging contaminants (ECs), exemplified by sulfamethoxazole (SMX). Results demonstrate that FZA effectively catalyzed the activation of peracetic acid (PAA), achieving a remarkable degradation of 99.8% under optimized conditions. Mechanistic investigations reveal that the FZA/PAA system can generate ·OH, 1O2, O2·ï¼, and Fe(Ⅳ), with ·OH playing a dominant role in ECs degradation. Additionally, the doped S facilitated electrochemical performance, Fe2+ regeneration and fixation in FZA. Practical application elucidated that the FZA/PAA system can work in complex environments to degrade various ECs without generating high-toxicity ingredients. Overall, valorizing SIA to FZA provides dual achievement in waste management and ECs removal.

Enhancing landfill efficiency to drive greenhouse gas reduction: A comprehensive study on best practices and policy recommendations.

This article investigates the pivotal role of non-hazardous waste landfills in achieving greenhouse gas (GHG) reduction objectives within the European Union (EU).1 This study leverages the experience of key stakeholders in the European landfilling, assesses the efficacy of 'best-in-class' landfill installations, evaluates their potential impact on GHG reduction, and offers concrete recommendations for operators and policymakers. 'Best-in-class' landfills exceed the commonly accepted best practices by implementing all the following practices: (1) an anticipated capture system during the operating phase, (2) prompt installation of the final cover and capture system, with use of an impermeable cover, (3) operated as bioreactor, keeping optimal humidity, (4) adequate maintenance and reporting, (5) recovery of captured gas and (6) treatment of residual methane emissions throughout the waste decomposition process. The main finding is that switching from the actual mix of practices to 'best in class' practices would reduce by ~21 MtCO2eq (-36%) the emissions due to the degradation of waste landfilled between 2024 and 2035, compared to the 'business-as-usual scenario', while also providing a renewable energy source, bringing potential avoided emissions and energy sovereignty. The findings underscore that in addition to implementing the organics diversion and waste reduction targets of the EU, adopting 'best-in class' landfill practices has the potential to bolster energy recovery, mitigate emissions and stimulate biomethane production, thereby advancing the EU environmental goals.

Resource recovery from legacy waste dumpsites in India: A path towards sustainable waste management.

Legacy waste dumpsites have been a significant environmental concern in India for many years. These dumpsites are characterized by the uncontrolled disposal of Municipal Solid Waste (MSW) and have led to various types of pollution and disease outbreaks. As India faces the challenges of rapid urbanization and increased waste generation and with over 3000 legacy waste dumpsites in the country, the need to address these legacy waste dumpsites has become paramount. As we continue to struggle extensively for waste management as well as space, landfill mining has been recognized as a promising way of recovering resources in our country by employing various technological and engineering advancements to extract valuable materials and energy from legacy waste streams. Unlike existing waste management approaches, this review explores the application of a novel Recovery Potential Index (RPI) for legacy waste dumpsites in India, which evaluates the feasibility of waste treatment facilities based on waste compositions and recovered material quantities. Depending on the RPI, recovered fine fractions can be sold as city compost or used as fill material, while recyclable, combustible, and inert fractions could be directed towards appropriate recycling or landfill uses. Unscientific and uncontrolled landfill mining practices could lead to unanticipated impacts on the nearby environment in the form of heavy contamination, thereby presenting this practice as a challenge in addition to the immense opportunities it provides.

Sustainable organic waste valorisation: A zero-waste approach.

The annual increase in global organic waste generation emphasises the need to develop a sustainable management platform to address environmental concerns. This study aims to explore sustainable treatments for the conversion of organic waste into energy in pursuit of zero-waste. The organic waste generated from the animal feed industry (referred to as WF) was used for the model compound in this study. 8.5 wt% of lipids were extracted from the WF, which contained unidentified impurities. Acid-catalysed transesterification yielded less than 80 wt% biodiesel might be due to the reversible reaction. In contrast, non-catalytic transesterification resulted in a significantly higher biodiesel yield (95.6 wt%), suggesting that this method was more effective at converting impure lipids into biodiesel compared to acid-catalysed transesterification. These results indicate the potential advantages of the non-catalytic approach, particularly when dealing with impure lipid sources. To minimise the generation of waste in the process, the WF residue produced after lipid extraction was converted into combustible gas (syngas) through pyrolysis. CO2 was used as a reactive medium in pyrolysis. In one-stage pyrolysis, the gas yield under CO2 was comparable to that under N2, indicating that CO2 did not react effectively with the volatiles derived from the WF residue. Enhanced CO2 reactivity was achieved via catalytic pyrolysis using a nickel-impregnated catalyst. Consequently, the combustible gas yield under CO2 was much higher than that under N2. This approach might contribute to maximising the efficiency of converting organic waste into renewable energy while simultaneously consuming CO2 during pyrolysis, thereby enhancing the sustainability of this approach.

Optimization of PET depolymerization for enhanced terephthalic acid recovery from commercial PET and post consumer PET-bottles via low-temperature alkaline hydrolysis.

The increasing demand for plastic has resulted in a surge in plastic waste production. Polyethylene terephthalate (PET), commonly used in beverage bottle manufacturing, is only partially recycled, with an estimated recycling rate of just 28.4% in 2019. This accumulation of plastic waste is harmful to the environment and living organisms, necessitating effective recycling methods for PET waste. One promising method is alkaline hydrolysis using NaOH, which can break down PET into its monomer components, terephthalic acid (TPA) and ethylene glycol (EG). This process not only recycles PET efficiently but also manages contaminants effectively, producing high-quality TPA, supporting the development of a circular economy. This study looks into PET depolymerization via alkaline hydrolysis at low temperature by investigating effects of various factors: pH levels, water to ethanol ratio, NaOH concentration, NaOH to PET ratio, reaction time, PET size, reusability of unreacted PET, air plasma pretreatment of PET, and different kinds of PET. Promisingly, PET conversion rates of over 90% and a TPA purity of 99.6% were achieved in this study highlighting the efficacy of alkaline hydrolysis in depolymerizing post-consumer PET waste. Ultimately, this research advances sustainable plastic waste management and supports the integration of PET into a circular economy framework.

A novel bio-coagulation/co-digestion/pyrolysis scheme for banana pseudostem waste management: techno­economic and sustainability approaches.

While several studies have focused on utilizing banana pseudostem waste (BPW) for wastewater treatment via bio-coagulation, this process still suffers from secondary pollution caused by the disposal of generated sludge. To avoid this pollution transfer issue, this study is the first to focus on the recyclability of post-coagulation sludge (PCS) to recover added-value products. For this purpose, BPW was used as a model bio-coagulant for the decontamination of laundry wastewater (LWW), followed by anaerobic digestion and pyrolysis schemes to recover biogas and biochar, respectively. In the first experiment, BPW succeeded in removing 55.44 ± 1.21%, 90.40 ± 3.09%, and 78.13 ± 2.44% of chemical oxygen demand (COD), turbidity, and surfactant, respectively, at the optimized condition (pH = 3.5, dosage = 2.34 g/L, stirring speed = 160.6 rpm, and settling time = 55.5 min). Inoculating the spent bio-coagulant with cattle manure (CM), with a mixing ratio of 1:1 (w:w), showed a biogas yield of 110.33 ± 6.02 mL/g COD. The synergetic effect of spent coagulant and microbes of CM was further validated by performing a COD mass balance, showing that about 31.52 ± 1.63% of CODfeed was converted to bio-CH4 (as COD). Further, the thermal treatment of digestate was successfully employed for biochar recovery at a yield of 0.58 ± 0.05 g biochar/g dry digestate. The study also revealed that the triple LWW treatment/biogas/biochar strategy could gain economic benefits with a payback period of 4.4 years. Hence, BPW could be used as a promising feedstock for pollution reduction, energy generation, and gaining profits.

Overcoming China's animal waste disposal challenge brought by elevated levels of veterinary antimicrobial residues and antimicrobial resistance.

Direct application of animal waste on farmlands was banned in China recently, rendering organic fertilizer production a sound solution for disposing of animal manures and recycling their materials and nutrients. Due to the overuse of antimicrobials in livestock and poultry farms, manure-based organic fertilizers often contain elevated residues of antimicrobials and abundant antimicrobial resistance genes. Land application of such products has caused significant concerns on the environmental pollution of antimicrobials, and the transmission and development of antimicrobial resistance (AMR), which is a major global health challenge. China's recent attempt to restrict the contents of antimicrobial residues in organic fertilizers encountered strong resistance from the industry as it would hinder the utilization of animal manures as a raw material. Reducing and even eliminating the use of antimicrobials in animal farms is the ultimate solution to the challenge of manure disposal posed by the elevated levels of antimicrobial residues and AMR. Phasing out the non-therapeutic use of antimicrobials, developing substitutes of antimicrobials, enhancing animal welfare in farms, promoting diversification of animal farms, and developing antimicrobial removal and disinfection technologies for animal waste are recommended to improve the veterinary antimicrobial stewardship and manure management in China's animal agriculture. These concerted measures would enhance the sustainability of crop and animal farming systems in China and mitigate the impact of antimicrobials and AMR to agro-environmental quality and human health.

A comprehensive review of current approaches on food waste reduction strategies.

Food waste is a serious worldwide issue that has an impact on the environment, society, and economy. This comprehensive review provides a detailed description of methods and approaches for reducing food waste, emphasizing the necessity of comprehensive strategies to tackle its intricate relationship with environmental sustainability, social equity, and economic prosperity. By scrutinizing the extent and impact of food waste, from initial production stages to final disposal, this comprehensive review underlines the urgent need for integrated solutions that include technological advancements, behavioral interventions, regulatory frameworks, and collaborative endeavors. Environmental assessments highlight the significant contribution of food waste to greenhouse gas emissions, land degradation, water scarcity, and energy inefficiency, thereby emphasizing the importance of curtailing its environmental impact. Concurrently, the social and economic consequences of food waste, such as food insecurity, economic losses, and disparities in food access, underscore the imperative for coordinated action across multiple sectors. Food waste can also be effectively reduced by various innovative approaches, such as technological waste reduction solutions, supply chain optimization strategies, consumer behavior-focused initiatives, and waste recovery and recycling techniques. Furthermore, in order to foster an environment that encourages the reduction of food waste and facilitates the transition to a circular economy, legislative changes and regulatory actions are essential. By embracing these multifaceted strategies and approaches, stakeholders can unite to confront the global food waste crisis, thereby fostering resilience, sustainability, and social equity within our food systems.

Estimation of the uncertainty of metal content in a batch of waste printed circuit boards from computer motherboards.

Electronic wastes are a valuable resource due to their critical and precious metal content. To include these wastes in recycling or recovery chains, it is necessary to precisely determine their metal content. Because analysing the whole sample of a batch of electronic waste is not practical, different preparation and sampling or subsampling steps are necessary. Sampling induces an error in the composition of the final sample compared to that of the initial batch, which finally leads to uncertainty in the final metal content measurement as compared to the "actual" batch metal content. The aim was to characterize the uncertainty in metal content of a batch of 372 kg of WPCB. Thirty-nine metals were analysed and thirty-two were considered: base, precious, rare-earths and critical metals. An empirical method (i.e. replicated measurement tests) was thus applied, based on statistical calculations according to Eurachem Guidelines. Uncertainty arising during the 3 different stages of the preparation process (primary, secondly and tertiary sampling steps) was calculated. For the analysed given weight (0.5 g), the shredding efficiency, which directly affects metal particle size distribution, was found to be the most important factor influencing the uncertainty. Uncertainties in base metal content, which is often concentrated in the coarsest particles, arose mainly from the last preparation step (tertiary sampling). Conversely, precious metals and rare-earths were finely ground during the 3 preparation steps, which led to low uncertainties, despite their low concentration in the waste (<337 mg/t for precious and < 35 mg/t for rare-earths).