Journal of Material Cycles and Waste Management最新文献

The challenge of managing Sewage Sludge (SS) intersects with environmental concerns, regulatory frameworks, and public perceptions. Integrating SS with Green Waste (GW) through co-composting presents a forward-thinking solution that caters to both waste management and sustainable agricultural practices. Co-composting of SS with GW contributes towards food, water, and energy nexus frameworks, aiming to generate a circular bioeconomy establishing a nutrient loop to improve food and waste systems resilience. The co-composting process not only diverts organic waste from landfills but also creates a nutrient-rich soil amendment. The current review delves into the synergistic benefits and the scientific and practical aspects of factors affecting the co-composting of SS with GW. It examines the interaction between SS and GW and its influence on the composting process, the quality of the resulting compost, and the phytotoxicity of compost. Moreover, a special focus on the evaluation of maturity and stability indicators is considered.

The expansion of Controlled Environment Agriculture (CEA) has increased agricultural waste, notably coconut coir from hydroponic systems. This study investigates hydrothermal carbonization (HTC) as a treatment for waste coir substrate at 180 °C to 300 °C to improve its fuel properties. HTC processing significantly raises the carbon content, fixed carbon, and calorific value of the resulting hydrochar while reducing volatile matter and contaminants such as potassium, sulfur, and chlorine. Combustion analysis shows enhanced fuel ratios, Volatile ignitability (19.90 MJ/kg), and combustibility indices (23.20 MJ/kg), indicating the potential of HTC-treated coir as a viable energy resource. This study shows that converting CEA byproducts into energy can help achieve South Korea’s 2050 carbon neutrality goals and address environmental and waste management challenges.

This study investigated the effects of biochar, fly ash, and biomass power plant ash on ammonia–nitrogen (NH₃) emission reduction and nitrogen retention during aerobic composting (AC) of chicken manure and corn straw. In detail, 9 groups treated with different proportions (4, 8, and 12%) of additives (biochar, fly ash, and biomass power plant ash) were designed through 21-day AC experiments. Further, the impacts of different temperatures (20, 40, and 60 °C) on nitrogen emission were explored and analyzed. Results showed that 8% biochar (T_1-2) reduced total NH₃ emission by 54.83% and peak emission by 70.26%, while increasing final total nitrogen by 22.40% versus the control. At the same time, it significantly increases the content of nitrate nitrogen and optimizes the nitrogen-transformation efficiency. Fly ash (T_2-2) and biomass power plant ash (T₃-₁) achieved 35.61 and 42.34% inhibition rates, respectively. Temperature experiments revealed optimal NH₃ suppression at 20 °C (T20), while 60 °C (T60) enhanced total nitrogen by 39.8% and organic matter degradation by 30.91%. Excessive additive proportions (12%) prolonged high-temperature phases, diminishing efficacy. The optimal strategy combines 8% biochar addition at 20 °C (initial stage) to mitigate NH₃ volatilization, followed by maintaining 60 °C to ensure composting efficiency and nitrogen retention. This approach balances emission reduction and nutrient conservation in AC processes.

The disposal of printed circuit boards (PCBs) from waste electrical and electronic equipment (WEEE) is highly hazardous, making reuse and recycling a challenge due to the presence of halogenated compounds as fire retardants. Reduction of halogenated compounds, along with energy and material recovery, can be accomplished through co-pyrolysis with biomass such as rice husk (RH), resulting in the production of gas, solid char, and primarily liquid oil. This study investigates the pyrolysis of PCB, RH, and a 1:1 mixture of PCB: RH. Thermal degradation of these samples was conducted at the temperature range of 25 °C to 700 °C, under nitrogen atmosphere. Lab scale experiments using a fixed bed reactor were conducted under the same conditions as the TGA analysis. The oil yield from PCB alone was very low (4%), which increased to 14% (250%) through (1:1) PCB: RH co-pyrolysis. GC–MS results showed that phenol and phenolic compounds in the PCB: RH oil increased to 76.12%, compared to 8.17% in the RH pyrolysis oil, which can be efficiently separated and repurposed for various industrial applications. Additionally, the process revealed a significant reduction in halogenated compounds for PCB: RH oil compared to the PCB oil, highlighting the effectiveness of co-pyrolysis in reducing hazardous byproducts.

The luxury personal goods industry is facing increasing pressure to improve economic and environmental sustainability in its production processes. Thus, efforts need to be made to improve some of the traditional operations performed in this sector. In fact, a gap is found in studies intending to enhance the operational efficiency of this sector. Thus, this study seeks to improve painting and glueing operations in this sector using the DMAIC (Define, Measure, Analyze, Improve, Control) methodology. The research was focused on analyzing existing practices, identifying inefficiencies, and implementing targeted improvements. Key findings show that restructuring filter management enabled a reduction of 258.07 kg of waste sent to landfill after two weeks of implementation, resulting in weekly savings of €112.19 and 88.72% reduction in disposal costs. In addition, standardizing filter types across different equipment improved operational efficiency, reduced inventory discrepancies and became a large area in the warehouse. The results highlight the effectiveness of integrating Lean and Six Sigma methodologies in optimizing production in the sector. The study concludes that systematic improvements generate substantial economic benefits and reduce the environmental footprint. This case study serves as a reference for similar industries seeking sustainable practices without compromising production quality and competitiveness. The research reinforces the importance of continuous improvement to achieve sustainability goals in manufacturing.

Rice husk (RH) is often used as biomass fuel or discarded, leading to significant environmental impacts. Rice husk ash (RHA), obtained by burning RH, contains 82–97% amorphous silica, making it a potential sustainable material. Use of RHA has various advantages like wide availability and the low cost, however, the use of it as a construction material is limited due to processing inefficiencies and an insufficient understanding of its properties. This study reviews RHA production technologies, its advanced properties, potential applications, environmental impacts and economic benefits. Furthermore, the effect of RHA on the mechanical properties, durability and permeability of concrete are evaluated. Studies reveal that burning temperature (500–700 °C for 2 h), duration, cooling rate, RH source, burning method and pretreatment techniques (acidic or alkaline) are key factors influencing the performance of RHA. Notably, incorporating 10–20% of RHA can optimize concrete strength. This study also identifies several research gaps, including the need for energy-efficient and sustainable RHA extraction techniques, its application in geopolymers and 3D concrete printing, and the development of eco-friendly building products. This review aims to disseminate the knowledge that can assist industrialists and researchers in designing innovative machinery, optimizing processes, and developing research strategies to promote the sustainable application of RH waste.

Fecal sludge (FS) is biohazardous waste from on-site sanitation (OSS) containers like septic tanks and pit latrines, potentially harming the environment if discharged untreated. The design of the FS treatment system depends on its characteristic properties. Earlier and already existing characterization studies have shown that FS age, OSS type, water inclusion, and usage of additives significantly impact FS characteristics. There are various sampling methods to collect and characterize the sample. However, no study has compared the sampling methods of FS, which may potentially impact characterization. This study compares composite and grab sampling methods by analyzing 15 samples of each collected from the same FS discharge during a vacuum truck emptying vehicle in Pilani, a town in Rajasthan, India. The characterization of FS samples from OSS revealed variations between the two sampling methods, even though the samples were obtained from the same FS discharge. In composite sampling, total solids (TS) varied from 14.9 to 90 g/l (mean: 42.3 g/l, median: 33.4 g/l), and chemical oxygen demand (COD) varied from 16 g/l to 122.7 g/l (mean: 54.7 g/l, median: 42.7 g/l). While in grab sampling, TS varied from 12.1 to 91.5 g/l (mean: 36.2 g/l, median: 25.6 g/l), and COD varied from 8.7 g/l to 114.7 g/l (mean: 43.9 g/l, median: 29.3 g/l). A paired Wilcoxon signed-rank test shows that sampling methods significantly affect the TS (p = 0.041) and COD (p = 0.018) of FS samples.

This study explored vermitechnology to treat coal mine waste (CMW) and convert it into organic manure using Eisenia fetida, focusing changes in microbial community structure, nutrient cycling, and heavy metal (HM) detoxification. Post-treatment, CMW-based feedstocks exhibited neutral pH, reduced organic carbon, and increased availability of nitrogen (N), phosphorus (P), and potassium (K), with WC1 [CMW + cow dung (1:1)] and WC2 [CMW + cow dung (2:1)] showing significant improvements. Microbial activity, assessed by microbial biomass carbon (MBC), compost respiration (BSR, SIR), and enzymatic activity (DHG, FDA), increased in all treatments, with WC1 showing the highest values. Vermicomposting also reduced the labile pool of HMs (Pb: 60.03%, Cu: 68.52%, Ni: 47.19%), with the highest reduction in WC1. Correlational and principal component analyses indicated that enhanced microbial abundance suppressed HM bioavailability. A PLFA-based study revealed that HMs-induced stress and feedstock composition altered microbial membrane fatty acid structures. Sobol sensitivity indices highlighted the microbial communities’ response to individual HMs. Overall, WC1 [CMW + cow dung (1:1)] proved most effective for microbial and earthworm growth, demonstrating its potential for reducing HM load in coal mine waste.

The growing adoption of electric vehicles leads to an increasing volume of end-of-life battery systems, posing significant sustainability and recycling challenges. Manual disassembly remains standard practice, but the diversity and complexity of electric vehicles battery system designs make the process labor-intensive, expensive and difficult to scale. Automation offers promising solutions, yet technological and procedural barriers remain. Lean management principles, focused on standardization, efficiency, and continuous improvement, can help overcome these challenges. This study presents a systematic literature review analyzing how lean methods are currently applied in the disassembly of electric vehicles battery systems. Findings show that lean approaches are frequently used to improve subprocess efficiency, reduce costs and processing time, and enhance sustainability. However, most research addresses isolated aspects, lacking an integrated, structured framework. Key gaps include the combination of lean with automation technologies, knowledge transfer into industrial practice, and comparative evaluation of different solutions using continuous improvement cycles. This study provides a comprehensive overview of current research and offers recommendations for developing efficient, scalable, and sustainable disassembly processes. It highlights the critical role of lean thinking in realizing a circular economy for electric vehicle battery systems through reuse and resource recovery.

Sewage sludge management is a pressing environmental challenge due to high greenhouse gas emissions and inefficiencies in traditional methods such as landfilling and incineration. This review explores emerging and transformative technologies that align with carbon sequestration and sustainable land use. Novel approaches such as biochar production via pyrolysis, CaO-based stabilization to form calcium carbonate (CaCO₃), and phosphorus recovery through struvite precipitation are emphasized for their dual roles in climate mitigation and enhancing soil fertility. Other innovative techniques, including hydrothermal carbonization and microbial stabilization, have been examined for their ability to stabilize carbon in persistent forms. This study highlights the novelty of combining carbon sequestration with nutrient recycling, which enables long-term environmental benefits. Biochar and Ca-based fertilizers demonstrate exceptional potential for integrating carbon capture with soil enhancement, whereas struvite offers an effective pathway for nutrient recovery. Environmental trade-offs—such as greenhouse gas emissions during treatment, potential contaminant risks, and energy demands—are assessed alongside the benefits of reduced synthetic fertilizer dependence, improved soil health, and carbon sequestration. Life cycle assessment (LCA) and economic analyses confirm the feasibility and sustainability of these technologies. This comprehensive review advances the understanding of innovative sewage sludge treatments, offering a framework for integrating carbon-negative solutions into waste management practices.

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