Decomposition Of Waste Research Articles

Fabrication of nutritional edible bowls with wheat bran, multigrain powder, refined flour, flax seed powder, fenugreek essential oil, and jaggery.

The recycling or decomposition of plastic waste poses challenges due to its non-organic nature. As a consequence of the unregulated production of plastic goods, a substantial quantity of plastic garbage has been generated. There is an increasing demand for sustainable substitutes for synthetic petrochemical-derived plastic products. The utilization of cake molds made from plastic materials has become increasingly prevalent and they have become widely employed household items. Bio-based bowls have the potential to serve as viable alternatives to their plastic counterparts. This study involved the fabrication of a bio-based healthy edible bowl mold using natural ingredients, including multigrain flour, refined flour (maida), jaggery, flaxseed, and fenugreek essential oil. A nutrient-rich edible bowl was developed by using different weight percentages (ranging from 0% to 10%) of wheat bran (WB). The addition of WB to the nutritious bowl resulted in the lowest levels of water absorption and oil absorption compared with the control group. The enhanced nutritional bowl demonstrated notable antioxidant activity. The inclusion of wheat bran resulted in a further enhancement of antioxidant action, with an approximate increase of 28% observed. The protein value of the nutritious bowl came to be 13.17 g/0.1 kg of protein. It was also revealed from an early soil degradation test that the bowl that was created exhibited biodegradability. The findings of this study offer a potentially viable method for developing a more sustainable substitute for cake molds/bowls made from plastic materials. © 2024 Society of Chemical Industry.

Statistical Methods in the Analysis of the Effect of Carbonisate on the Hardness of Epoxy-Resin-Based Composites

This research concerns the manufacture and characterisation of epoxy composites with the addition of carbonisate, obtained by the pyrolysis of MDF (medium-density fibreboard) furniture board waste. The laminated composites were made by hand lamination, with the carbonisate used as a filler to improve the mechanical properties of the composite. The carbonisate was obtained by the thermal decomposition of MDF waste in an anaerobic environment by pyrolysis, which is an efficient method of waste management and material recycling. The resulting carbonisate was integrated into an epoxy resin matrix to investigate its potential as a reinforcing agent. The article describes a study on the hardness of epoxy-resin-based composites to which carbonisate was added in different fractions and percentages. The aim of the research was to test the possibility of using char as a component in improving the mechanical properties of epoxy composites with a view towards creating a durable recycled material with optimal parameters. As part of the study, a statistical analysis of the results of hardness measurements was carried out to accurately assess the effect of the quantity and size of the carbonate particles on the mechanical properties of the materials. The analysis identified significant differences between samples and verified the repeatability of the results. It was found that the addition of carbonisate to the A0 base sample (without the addition of carbonisate) leads to a significant hardening of the material. This was confirmed by the higher medians of samples A01 (carbonisate 5% with a 0.5 mm fraction), A02 (carbonisate 7.5% with a 0.5 mm fraction), and A03 (carbonisate 5% with a 1.0 mm fraction) compared to the base sample. The most homogeneous hardness was shown in sample A02, with the highest concentration of results and the lowest values of standard deviation and spread. The results indicated that the addition of carbonate significantly increased the hardness of the composite materials, with optimal stability achieved at 7.5% (by weight) of carbonate with a 0.5 mm fraction. The conducted research precisely determined the influence of the amount and characteristics of carbonisate particles on the mechanical properties of the materials, which enables the more effective designing of future composites. The statistical results provide a reliable basis for evaluating the potential applications of these materials in various industrial sectors, such as construction, automotive and aerospace, where high hardness and durability are important.

Efficient, electrochemical degradation of organic pollutants via nanofibrous Pt/Ir–RuO2 electrode with enhanced stability

A diverse range of surfactants and chelating agents are frequently used in industrial processes, especially in the decontamination of nuclear facilities for decommissioning. To treat and degrade these organic pollutants, electrooxidation (EO) has emerged as a cost-effective method. Along these lines, in this work, a nanofibrous electrode was constructed to facilitate efficient EO. Among various metal oxide for EO, RuO2 is known for its excellent electrochemical activity, which was fabricated into a nanofiber structure with a large specific surface area and doped with IrO2 to increase its stability. In addition to the use of nanofibrous Ir–RuO2, a Pt intermediate layer was incorporated to increase both structural stability and electrical conductivity. The nanofibrous electrode with a Ru:Ir composition of 9:1 showed an electrochemical activation area 1.7 times larger and a charge transfer resistance 4.7 times smaller than a flat-type electrode with the same composition. Efficient degradation (99%) of organic pollutants (sodium dodecyl benzene sulfonate, Triton X-100, ethylenediaminetetraacetic acid, and nitrilotriacetic acid (NTA)) was successfully performed using the nanofibrous electrode. Effective decomposition of radioactive waste (NTA combined with Co ions) with 99% degradation within 4 h was achieved.

Hydrogen and carbon nanotube production from microwave-assisted catalytic decomposition of plastic waste

Plastic waste has become an alternative resource for generating carbon-free hydrogen and valuable carbon. The challenge lies in the efficient catalytic pyrolysis of plastics, the energy-intensive nature of decomposition, and reactor configuration. In a single-stage process, the presence of solid plastic with the catalyst leads to carbon block formation, inhibiting the growth of filamentous structure. We proposed a two-stage process incorporating microwave-assisted heating, encompassing thermal pyrolysis at 500 ˚C, followed by catalytic chemical vapor deposition at 800 ˚C. Transition metals, including iron, nickel, and cobalt, and their alloys were examined for catalytic performance along with assessments of catalyst-to-feed mixing ratios and catalyst stability. Comprehensive characterization techniques were employed to explore nanocrystal size, dispersion, reduction behavior, and support interaction strength. The FeNi/Al2O3 catalyst exhibited the highest yields among the selected catalysts, attributed to its optimized nanocrystalline size and interaction strength. These characteristics facilitated the production of 445 mg/gplastic of carbon nanotubes and 52.1 mmol/gplastic of hydrogen during low-density polyethylene decomposition, corresponding to the extraction of 52 % carbon and 72 % hydrogen relative to theoretical content. The catalyst exhibited a sustained efficiency over ten consecutive cycles, yielding 513 mg/gplastic of highly crystalline multiwall carbon nanotubes, with electrification demonstrating promise for sustainably converting plastic waste into carbon-free hydrogen and carbon.

Influence of Self-Heating on Landfill Leachate Migration

The hydrodynamic processes of landfill leachate migration in the base of a solid waste landfill can have a critical impact on the natural environment. In the case of improper operation of municipal solid waste placement facilities, highly contaminated leachate may penetrate into groundwater and subsequently into surface water. This work addresses fundamental issues of multicomponent fluid propagation in a multilayer porous medium, taking into account temperature inhomogeneities caused by waste decomposition with heat release. The regimes of diffusion and convection of leachate water penetrating into soil layers in the base of municipal solid waste facilities are numerically studied. Archival data from a set of field and laboratory measurements in the area of the operating landfill are used to model the features of pollutant propagation and determine migration parameters. The process of pollutant propagation and migration is described by quantitative values of dry residue content in leachate. Factors that have a significant impact on the migration of leachate are considered. The main ones are convective transfer, diffusion, and properties of the geological composition of the landfill base, which are taken into account in the mathematical formulation of the problem. The calculations show that leachate self-heating can substantially intensify leachate filtration and has to be taken into account in the assessment of leachate migration rate.

Methane Generation Potential of the Easily Degradable Group of Landfilled Municipal Solid Waste

Municipal solid waste (MSW) remains in sanitary landfills for many years. To maintain a circular economy, assessing the feasibility of reinserting MSW excavated from sanitary landfills into the production chain is important. This reduces environmental impacts, helping to minimize soil, water, and air pollution resulting from the decomposition of waste in landfills. In addition, it promotes economic benefits from the energy recovery of waste, such as biomass, which can generate electricity and heat, contributing to a sustainable energy matrix. The present study aimed to evaluate the easily degradable MSW group with 24 years of landfilling (ED-24) regarding its potential for methane generation. The ED group consisted of putrescible organic matter, wood, paper, cardboard, and pruning landfilled at a sanitary landfill in Southeastern Brazil. The feasibility of valuing ED-24 as a substrate for anaerobic digestion was assessed by analyzing its physical, chemical, and biochemical characterization and calculating its theoretical methane yield (TMY). The total volatile solids (TVS) and holo-cellulose contents of ED-24 were 73.45% and 61.39%, respectively, on a dry-weight basis. These values were in the range of those determined for non-landfilled lignocellulosic materials. Thus, 24 years of landfilling partially degraded the anaerobically lignocellulosic materials. The TMY of ED-24 was 233.41 mL CH4/g TVS, indicating a potential to generate methane. Despite the high lignin value, ED-24 can be valued as a substrate for anaerobic digestion.

OBAT KUMUR EKSTRAK ETANOL KULIT BATANG KAYU MANIS (CINNAMOMUM VERUM J.PRESL) SEBAGAI PENGHAMBATAN PERTUMBUHAN BAKTERI STREPTOCOCCUS MUTANS

Bad breath is caused by volatile sulfur compounds (VSCs) produced by the anaerobic bacteria Streptococcus mutans through the decomposition of food waste. This problem can be overcome with antibacterial mouthwash. Cinnamon contains essential oils, phenols, flavonoids, saponins and terpenoids, which have antibacterial properties. This study aimed to formulate a mouthwash from ethanol extract of cinnamon and evaluate its physical properties, stability, and inhibitory power against Streptococcus mutans using the Kirby-Bauer method. This research was experimental by making mouthwash using cinnamon extract with concentrations of 10% (FI), 12.5% ​​(FII), and 15% (FIII). The results of the research showed that the mouthwash preparations were brick red in color with different intensities, all preparations were homogeneous, had a pH according to standards except for FII and all preparations did not meet the required viscosity values. The stability test showed that the preparation was stable in storage except for the viscosity parameter FIII. The results of the antibacterial activity test showed that the inhibitory power of FI, FII, FIII against Streptococcus mutans bacteria was 7.33 mm, 8.50 mm, 9.33 mm respectively. The inhibitory power of FII and FIII was better than the positive control, namely total care-antibacterial mouthwash (8.33 mm).

A Thermogravimetric Analysis of Biomass Conversion to Biochar: Experimental and Kinetic Modeling

This study investigates the pyrolytic decomposition of apple and potato peel waste using thermogravimetric analysis (TGA). In addition, using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS), the influence of pyrolysis temperature on the physicochemical characteristics and structural properties of biochar was studied. The degradation of biomass samples was studied between 25 °C and 800 °C. Although apple and potato peel decomposition present similar thermogravimetric profiles, there are some differences that can be evidenced from DTG curves. Potato peel showed one degradation peak in the range 205–375 °C with 50% weight loss; meanwhile, the apple peel exhibited two stages: one with a maximum at around 220 °C and about 38% weight loss caused by degradation of simple carbohydrates and a second peak between 280 °C and 380 °C with a maximum at 330 °C, having a weight loss of approximately 24%, attributed to cellulose degradation. To gain more insight into the phenomena involved in biomass conversion, the kinetics of the reaction were analyzed using thermal data collected in non-isothermal conditions with a constant heating rate of 5, 10, 20, or 30 °C /min. The kinetic analysis for each decomposed biomass (apple and potato) was carried out based on single-step and multi-step type techniques by combining the Arrhenius form of the decomposition rate constant with the mass action law. The multi-step approaches provided further insight into the degradation mechanisms for the whole range of the decomposition temperatures. The effect of temperature on biomass waste structure showed that the surface morphologies and surface functional groups of both samples are influenced by the pyrolysis temperature. A higher pyrolysis temperature of 800 °C results in the disappearance of the bands characteristic of the hydroxyl, aliphatic, ether, and ester functional groups, characteristic of a porous surface with increased adsorption capacity. Therefore, this study concludes that biomass waste samples (apple and potato) can produce high yields of biochar and are a potential ecological basis for a sustainable approach. The preliminary adsorption tests show a reasonably good nitrate removal capacity for our biochar samples.

Plasmagestützter Prozess mit Einzelatom‐Katalysatoren zur Nachhaltigen Umwandlung von Kunststoffabfällen

AbstractDie stetig steigende Menge an Kunststoffabfällen erfordert effektive Lösungen zur Bewältigung dieser Herausforderung. In dieser Studie stellen wir eine neuartige plasmagestützte Strategie zur schnellen Zersetzung verschiedener Plastikabfälle, einschließlich Mischungen, in hochwertige Kohlenstoffnanomaterialien und Wasserstoff vor. Die H2‐Ausbeute und die H2‐Selektivität, die durch die katalysatorfreien plasmagestützten Prozesse erzielt wurden, sind 14,2‐ bzw. 5,9‐mal höher als bisher unter ähnlichen Bedingungen mit konventioneller thermischer Pyrolyse erreicht wurde. Bemerkenswert ist, dass dieser katalysatorfreie Plasmaprozess einen signifikant höheren Energieertrag an H2 (gH2/kWh) im Vergleich zu anderen Pyrolyseprozessen liefert. Durch die Kopplung von Plasmapyrolyse mit thermischer Katalyse durch den Einsatz von atomar dispergierten Katalysatoren 1 Gew.‐ % M/CeO2 (M=Fe, Co und Ni) kann die Wasserstoffproduktion weiter gesteigert werden. Insbesondere der 1 Gew.– %Co/CeO2 Katalysator zeigte eine hervorragende katalytische Leistung über 10 Zyklen der Kunststoffabfallzersetzung hinweg und erreichte die höchste H2‐Ausbeute von 46,7 mmol/gplastic (entsprechend 64,4 % der theoretischen H2‐Ausbeute) und nahezu 100 % Wasserstoffatom‐Rückgewinnungseffizienz im 7. Zyklus. Atomar dispergiertes Fe auf der CeO2‐Oberfläche (1 Gew.– % Fe/CeO2) konnte im integrierten plasma‐thermischen Katalyseprozess eine H2‐Ausbeute erzielen wie sie sonst nur mit deutlich höheren Beladungen von Fe‐Partikeln auf der CeO2‐Oberfläche (10 Gew.– % Fe/CeO2) erreicht wird. Daher wurde demonstriert, dass Einzelatom‐Katalysatoren einen vielversprechenden Weg für ein kostengünstiges und effizientes chemisches Kunststoffrecycling darstellen. Durch eine Kombination aus Experiment und Modellierung haben wir ein tiefgehendes Verständnis der katalytischen Mechanismen der untersuchten Einzelatom‐Katalysatoren im entwickelten plasmagestützten Prozess erzielt. Dieser innovative und unkomplizierte Ansatz bietet eine vielversprechende und schnelle Strategie zur kontinuierlichen Umwandlung verschiedener Kunststoffabfallströme, einschließlich gemischter und kontaminierter Quellen, in hochwertige Produkte, die eine Kreislaufwirtschaft für Kunststoffe unterstützen.

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.

3D Porous Gel from the Orthogonal-junction of Nanosheet Photosensitizers with Efficient and Selective Photosensitization

Photocatalysis waste decomposition is a promising candidate for efficient cleaning of volatile organic compounds (VOCs) with enhanced safety because of the self-degradation of toxic compounds by reactive oxygen species (ROS) under light irradiation. However, the complete removal of pollutants remains challenging due to the inert characteristics of their inactivity in the presence of electrophilic ROS. Herein, a new strategy for efficient degradation of inert VOCs such as benzaldehyde has been proposed, basing on the synergism of selective adsorption and chemical activation by the construction of 3D porous gel through an orthogonal-junction of nanosheet-shaped photosensitizers. The key to the success of the combination is the use of hierarchically assembled hydrogen bonded laminates (HBLs) as gelation scaffolds. The backbone could integrate organic photosensitizers (PSs) into robust gel skeleton with enhanced ROS generation, which promotes the photocatalytic degradation. Especially, the backbone is able to directionally recognize glue clusters by hydrogen bonding to result in orthogonal 3D gel, giving remarkable selective adsorption for inert aromatic aldehydes. The synergistic integration of chemical activation and selective entrapment gives rise to unusual rapid photo-degradation for carbonyl compounds, resulting in efficient removal of inert pollutants from the environment without any adverse effect.

Highly effective direct conversion of H2S into COx-free H2 and S at low temperature over novel MoxC@ZrO2 microwave catalysts

Direct decomposition of H2S into H2 and S is an attractive alternative to the Claus process, because COx-free H2 and S can be simultaneously recovered from an abundant and toxic waste gas, which has huge social economic and ecological environmental benefits. However, it is still a great challenge to achieve the direct H2S decomposition reaction with high efficiency due to the thermal equilibrium limitation. Herein, a core-shell structured MoxC@ZrO2 was developed as novel microwave catalyst for microwave catalytic H2S decomposition. More specifically, the H2S conversion over MoxC@ZrO2 catalyst is as high as 99.9% at 650 °C, which immensely surpasses the H2S equilibrium conversion (6.1% at 650 °C). This study provides an effective strategy for the design of highly active microwave catalysts, and supplies a strategy for efficiently catalytic decomposition of H2S waste and recovering high-value hydrogen and sulfur at lower reaction temperatures.

Plasma-Enabled Process with Single-Atom Catalysts for Sustainable Plastic Waste Transformation.

In this study, we present a novel plasma-enabled strategy for the rapid breakdown of various types of plastic wastes, including mixtures, into high-value carbon nanomaterials and hydrogen. The H2 yield and selectivity achieved through the catalyst-free plasma-enabled strategy are 14.2 and 5.9 times higher, respectively, compared to those obtained with conventional thermal pyrolysis. It is noteworthy that this catalyst-free plasma alone approach yields a significantly higher energy yield of H2 (gH2/kWh) compared to other pyrolysis processes. By coupling plasma pyrolysis with thermal catalytic process, employing of 1 wt.% M/CeO2 atomically dispersed catalysts can further enhance hydrogen production. Specifically, the 1 wt.% Co/CeO2 catalyst demonstrated excellent catalytic performance throughout the 10 cycles of plastic waste decomposition, achieving the highest H2 yield of 46.7 mmol/gplastic (equivalent to 64.4% of theoretical H2 production) and nearly 100% hydrogen atom recovery efficiency at the 7th cycle. Notably, the H2 yield achieved over the atomically dispersed Fe on CeO2 surface in the integrated plasma-thermal catalytic process is comparable to that obtained with Fe particles on CeO2 surface (10 wt.%). This innovative and straightforward approach provides a promising and expedient strategy for continuously converting diverse plastic waste streams into high-value products conducive to a circular plastic economy.

Assessing Greenhouse Gas Emissions and Methane Production During Post-Landfill Maintenance in Kish Island: A LandGEM Simulation Approach

Background: Municipal solid waste (MSW) landfills are significant contributors to the emission of greenhouse gases, particularly methane, during the breakdown of waste materials. Researchers have undertaken extensive investigations into quantifying methane emissions from landfills, utilizing various methodologies beyond reliance on the LandGEM model. Numerous studies have underscored the efficacy of this model in predicting methane generation and exploring its utility in activities such as energy generation and emission mitigation strategies. Objectives: Municipal solid waste landfills are vital contributors to greenhouse gas emissions, notably methane, during waste decomposition. Significant research has focused on estimating methane output from landfills, utilizing various approaches beyond the LandGEM model. Studies highlight the model's potential in assessing methane generation and its relevance to activities like energy generation and emission management. Methods: The LandGEM simulation model is employed to forecast future waste generation and provide valuable insights into the environmental consequences of landfill management on the island. By analyzing population data and waste generation statistics from 2023 to 2042, the study utilizes the LandGEM software to estimate methane emissions, incorporating site-specific data and waste composition analysis. Results: The findings reveal that 36% of the total waste on Kish Island consists of putrescible material, with food waste being a significant component. Over the study period, approximately 1,282,637 tons of waste are projected to be disposed of in the Kish landfill. The LandGEM model predicts the highest landfill gas emission in 2043, primarily methane, along with carbon dioxide and non-metallic organic compounds. The estimated quantities for these gases in 2043 are 5.415E+03, 1.486E+04, and 2.327E+02 metric tons, respectively. Conclusions: This research highlights the importance of tailored waste management strategies to mitigate environmental impacts and emphasizes the need for efficient gas collection systems. A proposed gas collection system combining vertical wells, horizontal trenches, and under-membrane pipes is discussed to enhance efficiency and reduce environmental risks. The study provides valuable insights into waste management and landfill gas emissions on Kish Island, underscoring the significance of accurate emission prediction and effective management to minimize environmental consequences and optimize the utilization of renewable energy resources.

Microbial Diversity Assessment in Soil from Dumping Sites: Isolation, DNA Extraction and Electrophoretic Analysis

This study aims to investigate the microbial diversity present in soil samples collected from various dumping sites, which are known for their complex and heterogeneous waste environments. The primary objective is to isolate and characterize the microbial communities inhabiting these soils, providing insights into their composition and potential ecological roles. Soil samples were collected by digging 5 cm deep at multiple dumping locations to ensure a representative sampling of the microbial populations. The collected soil samples underwent a serial dilution process, extending up to 10^-9 and 10^-10 dilutions, to facilitate the isolation of individual microbial colonies. These diluted samples were then inoculated onto Standard Potato Dextrose Agar (PDA) media, a nutrient-rich medium conducive to microbial growth. Following an incubation period, distinct bacterial colonies were observed and isolated for further analysis. DNA was extracted from the isolated bacterial colonies using a standard DNA extraction protocol. The quality and purity of the extracted DNA were assessed through gel electrophoresis, a technique that separates DNA fragments based on their size. Remarkably, the electrophoretic analysis revealed clear and distinct DNA bands along with RNA bands, indicating successful extraction of high-quality microbial DNA. Notably, this was achieved without the use of proteinase treatment, which is typically employed to remove protein contaminants from DNA samples. The results of this study underscore the robustness of the methodologies employed in isolating and characterizing microbial DNA from soil samples collected at dumping sites. The presence of distinct DNA and RNA bands highlights the effectiveness of the DNA extraction process, even in the absence of proteinase treatment. These findings provide valuable insights into the microbial diversity within dumping site soils, suggesting a rich and varied microbial community that may play significant roles in soil health and waste decomposition.

Decomposition and fragmentation of conventional and biobased plastic wastes in simulated and real aquatic systems

AbstractPlastics play a crucial role in our daily lives. The challenge, however, is that they become waste and contribute to a global environmental problem, increasing concerns about pollution and the urgent need to protect the environment. The accumulation and fragmentation of plastic waste, especially micro- and nanoplastics in aquatic systems, poses a significant threat to ecosystems and human health. In this study, the decomposition and fragmentation processes of conventional and biobased plastic waste in simulated water bodies (waters with different pH values) and in real water systems (tap water and seawater) are investigated over a period of one and six months. Three types of plastic were examined: thermoplastic polyethylene terephthalate and thermoset melamine etherified resin in the form of nonwovens and biobased polylactic acid (PLA) in the form of foils. Such a comprehensive study involving these three types of plastics and the methodology for tracking degradation in water bodies has not been conducted before, which underlines the novelty of the present work. After aging of the plastics, both the solid fraction and the leachate in the liquid phase were carefully examined. The parameters studied include mass loss, structural changes and alterations in functional groups observed in the aged plastics. Post-exposure assessment of the fragmented pieces includes quantification of the microplastic, microscopic observations and confirmation of composition by in situ Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy. The leachate analysis includes pH, conductivity, turbidity, total carbon and microplastic size distribution. The results highlight the importance of plastic waste morphology and the minor degradation of biobased PLA and show that microfibers contribute to increased fragmentation in all aquatic systems and leave a significant ecological footprint. This study underlines the crucial importance of post-consumer plastic waste management and provides valuable insights into strategies for environmental protection. It also addresses the pressing issue of plastic pollution and provides evidence-based measures to mitigate its environmental impact. Graphical abstract

Performance of Effective Microorganism (EM) in Food Waste Composting and Their Association with Seed Germination on Kale Seed

Food waste has an influence throughout the whole food supply chain, from production to consumption. Composting effectively and affordably reduces the need for synthetic fertilizers, water, soil erosion, pesticides, and soil carbon storage. Composting may also improve crop yields and soil fertility, leading to more sustainable farming practices. The potential of efficient microorganisms (EM) for dehydrated food waste decomposition was investigated in this study. The research assessed the temperature and pH profiles during composting, whereas nitrogen, phosphorus, potassium, organic content, and E. coli were measured in mature composts. Therefore, the study revealed that EM greatly hastened the composting process by boosting critical factors such as temperature, pH, nitrogen content (TN : 1.17±0.6%, TP: 0.059±1.92%, K: 0.12±5.3%) organic enrichment (85%), and E-coli (<1 MPN/g). The germination index (GI) of kale seed was then analysed with the study’s findings indicating an 80% soil-compost ratio was the best. This research investigates the use of effective microorganisms (EM) to transform food waste into beneficial agricultural resources, with favourable results for soil health and kale seed germination. Researchers and circular economy officials may use the results to promote sustainable agriculture. The research helps to minimize landfill food waste, methane emissions, and synthetic fertilizer consumption, all of which benefit the environment. Farmers and gardeners may use the findings to boost soil fertility and crop yields on a budget. This research indicates that food waste may be transformed into useful resources, encouraging sustainable and eco-friendly agricultural.

Acceleration of Organic Compost Supply Using Microbial Consortium Formulation on Various Organic Wastes and their Effect on Sweet Corn

Organic waste, primarily originating from agricultural sources, remains underutilized in Indonesia, despite its substantial potential as an organic fertilizer. Consequently, it is imperative to comprehend the technology capable of efficiently decomposing organic matter and yielding high-quality compost. This study aimed to investigate the impact of a microbial consortium compris-ing Bacillus sp., Pseudomonas sp., Trichoderma sp., and Aspergillus sp. on the decomposition of organic waste derived from rice, sugarcane, corn and as well as to examine its application to sweet-corn (Zea mays var. saccharata). The study used a factorial randomized block design, featuring two primary factors, compost types and their respective doses. This design in total of nine treatments, each replicated three times, thus resulting in a sum of 27 experimental units. The treatments were RSC: Rice straw compost; SLC: Sugarcane leaves compost; CHC: Corn husk compost; D7.5: Compost dose of 7.5 t ha-1; D15: Compost dose of 15 t ha-1; D22.5: Compost dose of 22.5 t ha-1. Moreover, an essential fertilizer, NPK, was applied at a rate of 200 kg/ha. The find-ings demonstrated a substantial impact of both compost types and doses on maize growth parameters, which encompassed plant height, leaf area, chlo-rophyll contentand dry weight. These effects were observed individually, without any interactions between the two factors. Furthermore, these treat-ments exhibited a discernible influence on corn yield. The highest to lowest yields were recorded as follows: CHC (9.29 t ha-1), RSC (8.72 t ha-1), and SLC (8.00 t ha-1). Combining organic compost with chemical fertilizer effectively prevented nutrient loss through denitrification and evaporation, facilitating nutrient retention and controlled release over time.

Ambient noise imaging for municipal solid waste landfill structure detection based on the common-midpoint two-station analysis with distributed acoustic sensing

SUMMARY Distributed acoustic sensing (DAS) enables high-density sampling of seismic wavefields at low cost compared to conventional geophones. This capability facilitates structural detection of a municipal solid waste (MSW) landfill, which is important for protecting the surrounding ecosystem. However, processing the vast amount of data from DAS array for ambient noise imaging can be computationally intensive. To address this, we employed the common-midpoint two-station (CMP-TS) analysis to enhance the efficiency of ambient noise imaging in the MSW landfill. CMP-TS analysis involves selecting pairs of traces at equal distances on both sides with the subarray midpoint as symmetry, which reduces the number of DAS array recordings for cross-correlation calculations. After positioning the DAS arrays linearly on top of the MSW landfill to automatically collect ambient noise, we used the CMP-TS analysis in the cross-correlation calculations to speed up the measurement of dispersion. The S-wave velocity structure of the study region was obtained quickly by inverting the extracted dispersion curves using the gradient optimization method. Ambient noise imaging based on CMP-TS analysis with DAS was applied to a test of an area-type MSW landfill. The resulting S-wave velocity section revealed a discontinuous low-velocity zone, validated by the high-density resistivity method. This low-velocity zone was interpreted as containing leachate from waste decomposition, and its discontinuity may be caused by excessive differences in the waste residues settling rates under compaction. Employing CMP-TS analysis in ambient noise data collected by DAS offers more cost-effective monitoring and a reliable basis for environmental pollution prevention and control.

Linking microbial population dynamics in anaerobic bioreactors to food waste type and decomposition stage

A key question in anaerobic microbial ecology is how microbial communities develop over different stages of waste decomposition and whether these changes are specific to waste types. We destructively sampled over time 26 replicate bioreactors cultivated on fruit/vegetable waste (FVW) and meat waste (MW) based on pre-defined waste components and composition. To characterize community shifts, we examined 16S rRNA genes from both the leachate and solid fractions of the waste. Waste decomposition occurred faster in FVW than MW, as accumulation of ammonia in MW reactors led to inhibition of methanogenesis. We identified population succession during different stages of waste decomposition and linked specific populations to different waste types. Community analyses revealed underrepresentation of methanogens in the leachate fractions, emphasizing the importance of consistent and representative sampling when characterizing microbial communities in solid waste.