Hasil untuk "Standardization. Simplification. Waste"

Olugboja Adedeji, Zenghui Wang

Abstract The accumulation of solid waste in the urban area is becoming a great concern, and it would result in environmental pollution and may be hazardous to human health if it is not properly managed. It is important to have an advanced/intelligent waste management system to manage a variety of waste materials. One of the most important steps of waste management is the separation of the waste into the different components and this process is normally done manually by hand-picking. To simplify the process, we propose an intelligent waste material classification system, which is developed by using the 50-layer residual net pre-train (ResNet-50) Convolutional Neural Network model which is a machine learning tool and serves as the extractor, and Support Vector Machine (SVM) which is used to classify the waste into different groups/types such as glass, metal, paper, and plastic etc. The proposed system is tested on the trash image dataset which was developed by Gary Thung and Mindy Yang, and is able to achieve an accuracy of 87% on the dataset. The separation process of the waste will be faster and intelligent using the proposed waste material classification system without or reducing human involvement.

Ronilo P. Antonio

The growing crisis of microplastic pollution poses serious environmental and public health challenges, yet despite Asia’s central role in plastic leakage and research growth, its scholarly landscape over the past decade remains unmapped. This study addresses this gap by conducting a comprehensive bibliometric analysis of 3,797 Scopus-indexed articles published between 2015 and 2025, employing an integrated approach that combines performance analysis, co-citation analysis, and co-word analysis using VOSviewer software. The results reveal an exponential surge in research output since 2019, with China, India, and Indonesia emerging as key contributors. Citation analysis highlights seminal works on atmospheric transport, soil contamination, and human ingestion as influential drivers of the field. Co-citation mapping identifies four intellectual clusters, mainly foundational conceptual frameworks, environmental pathways, global plastics accounting, and ecological impacts. Meanwhile co-word analysis uncovers three thematic domains: pollution sources and detection, ecological and biological effects, and environmental fate and transport. Overlay visualization further demonstrates a temporal shift from early descriptive and methodological studies toward interdisciplinary, solution-oriented research integrating ecological risk assessment and human health concerns. By synthesizing a decade of scholarship, this study provides a critical evidence base for guiding future research priorities and informs risk assessment strategies, policy design, and global governance efforts aimed at mitigating the escalating microplastics crisis.

G. Ischia, L. Fiori

Hydrothermal carbonization (HTC) is an emerging path to give a new life to organic waste and residual biomass. Fulfilling the principles of the circular economy, through HTC “unpleasant” organics can be transformed into useful materials and possibly energy carriers. The potential applications of HTC are tremendous and the recent literature is full of investigations. In this context, models capable to predict, simulate and optimize the HTC process, reactors, and plants are engineering tools that can significantly shift HTC research towards innovation by boosting the development of novel enterprises based on HTC technology. This review paper addresses such key-issue: where do we stand regarding the development of these tools? The literature presents many and simplified models to describe the reaction kinetics, some dealing with the process simulation, while few focused on the heart of an HTC system, the reactor. Statistical investigations and some life cycle assessment analyses also appear in the current state of the art. This work examines and analyzes these predicting tools, highlighting their potentialities and limits. Overall, the current models suffer from many aspects, from the lack of data to the intrinsic complexity of HTC reactions and HTC systems. Therefore, the emphasis is given to what is still necessary to make the HTC process duly simulated and therefore implementable on an industrial scale with sufficient predictive margins.

Sayan Mukherjee, Shashank Pal, Subhasis Ghosh et al.

Malachite Green is a persistent pollutant, and it has been reported to cause many harmful health hazards for both humans and aquatic organisms. Growing use of plastic is posing a lot of problems and the most pertinent of which is perhaps the treatment of plastic waste. In the present work, plastic waste has been pyrolyzed, annealed and treated with sodium hydroxide to synthesize a char. Then this char has been used to remove the cationic dye Malachite Green from water and was observed highest removal of Malachite Green by the char was 99.3 %. From the thermodynamic study, it was observed that the value of Gibbs free energy was negative across all the temperature thereby denoting that the process was spontaneous. The process was optimized with an Artificial Neural Network system and from there it was observed that the Levenberg-Marquardt backpropagation model best optimized the experimental data. The char also exhibited high efficiency for the purpose of removing other cationic dyes and polyaromatic hydrocarbons, whereas showing a lower affinity for anionic dyes and pharmaceutical compounds.

Iris Borowy

This paper examines the early development of international waste governance from 1966 to 1976. As industrialised nations generated more waste due to urbanisation and changing consumption, international organisations faced pressure to respond. The World Health Organization led efforts by creating the International Reference Centre for Wastes Disposal (IRCWD) in collaboration with the Swiss Federal Institute for Water Supply, Sewage Purification and Water Pollution Control (EAWAG) and the International Association for Public Cleansing (INTAPUC). The IRCWD aimed to centralise global waste management knowledge and coordination. However, institutional fragmentation, funding issues and differing views on whether waste was a technical or systemic issue hindered its success. While some saw waste as a symptom of flawed modernisation, most treated it as a technical problem requiring improved disposal methods. Competition from other organisations, WHO ambivalence, and reluctance to challenge economic systems weakened momentum. Ultimately, waste became a shared concern but was addressed in fragmented ways. The study shows how institutional and political factors, rather than environmental priorities, shaped early international waste policy.

H.U. Modekwe, I.M. Ramatsa, M.A. Mamo et al.

The study focuses on “treating waste with waste” through the removal of toxic metals from gold mine wastewater using polysulfone (PSF) membrane infused with waste plastic derived-multi-walled carbon nanotube (MWCNTs) as an innovative approach. MWCNTs synthesized from waste polypropylene (PP) plastics by the chemical vapour deposition (CVD) method were purified in oxidizing acid, and different loadings (0, 0.05, 0.10, and 0.15 wt%) were incorporated into the PSF membrane to form mixed matrix membranes (MMM) via phase inversion technique. Fabricated pristine and nanocomposite membranes’ properties: hydrophilicity, thermal stability, and morphology, were ascertained by the water contact angle measurement, thermogravimetry analysis, and scanning electron microscopy, respectively. Results show that incorporating plastic-derived-MWCNTs into the matrices of PSF polymer significantly enhanced the properties of all fabricated MWCNTs/PSF nanocomposite membranes compared to pristine PSF. The flux and rejection of metals increased with MWCNTs loading. Iron (Fe) and nickel (Ni) removal by pristine PSF were 70.2% and 11.4%, respectively, while optimal Fe and Ni rejection of 91% and 74%, respectively, were obtained with 0.10 wt% MWCNT loading. The results obtained in this work revealed that incorporating different loadings of plastic-derived-MWCNTs onto the PSF polymer matrix impacted its surface properties, and improved flux, and removal efficiency. Therefore, utilizing waste plastics as a precursor in CNTs production will save on the cost of CNTs and provide a sustainable plastic waste management option, as well as open up vast prospects at the industrial scale in the potential for application in environmental remediation (such as in membrane separation).

B. van Straten

J. D. Martínez, Natalia Cardona-Uribe, R. Murillo et al.

Pyrolysis offers the possibility to convert waste tires into liquid and gaseous fractions as well as a carbon-rich solid (CBp), which contains the original carbon black (CB) and the inorganic compounds used in tire manufacture. Whilst both liquid and gaseous fractions can be valorized without further processing, there is a general consensus that CBp needs to be improved before it can be considered a commercial product, seriously penalizing the pyrolysis process profitability. In this work, the CBp produced in a continuous pyrolysis process was demineralized (chemical leaching) with the aim of recovering the CB trapped into the CBp and thus, producing a standardized CB product for commercial purposes. The demineralization process was conducted by using cheap and common reagents (HCl and NaOH). In this sense, the acid treatment removed most of the mineral matter contained in the CBp and concentration was the main parameter controlling the demineralization process. An ash content of 4.9 wt% was obtained by using 60 min of soaking time, 60 °C of temperature, 10 mL/g of reagent/CBp ratio and HCl 4 M. The demineralized CBp (dCBp) showed a carbon content of 92.9 wt%, while the FRX analysis indicated that SiO2 is the major component into the ash. The BET surface area was 76.3 m2/g, and textural characterizations (SEM/EDX and TEM) revealed that dCBp is composed by primary particles lower than 100 nm. Although dCBp showed a low structure, the surface chemistry was rich in surface acidic groups. Finally, dCBp was used in Styrene Butadiene Rubber (SBR) compounding, probing its technical feasibility as substitute of commercial CB N550.

Hanieh Moshtaghian, K. Bolton, Kamran Rousta

Upcycled foods contain unmarketable ingredients (e.g., damaged food produce, by-products and scraps from food preparation) that otherwise would not be directed for human consumption. Upcycled food is a new food category and thus faces several challenges, such as definition development, inclusion in the food waste management hierarchy and public acceptability. This review provides an overview of these three challenges. The upcycled food definitions have been developed for research, food manufacturers, and multi-stakeholders use. Thus, there is a need for a consumer-friendly definition for the general public. A simplified definition is proposed to introduce these foods as environmentally friendly foods containing safe ingredients that otherwise would not have gone to human consumption such as damaged food produce, by-products and scraps from food preparation. Moreover, an updated version of the food waste management hierarchy has been proposed by including the production of upcycled foods as a separate waste management action that is less preferable than redistribution but more favourable than producing animal feed. Furthermore, consumer sociodemographic characteristics and beliefs, as well as food quality cues and attributes, were identified as crucial factors for the public acceptability of these foods. Future research should address these challenges to facilitate the introduction of upcycled foods.

Narendra Kuppan, Midhila Padman, Manjushree Mahadeva et al.

Bioremediation, an advanced and environmentally sustainable technology, utilizes biological microorganisms to mitigate pollution. This review combines insights from two perspectives: one focusing on the mechanisms, applications, and types of bioremediation, and the other examining the transformative potential of integrating Internet of Things (IoT), Artificial Intelligence (AI), and biosensors in pollution management. The first perspective delves into the effectiveness of bioremediation in decomposing and detoxifying hazardous substances, emphasizing its cost-effectiveness and eco-friendliness compared to conventional methods. In-situ and ex-situ bioremediation methods are analyzed, along with intrinsic and engineered techniques, and phytoremediation strategies for heavy metal removal. The review underscores the growing importance of bioremediation in addressing industrial effluents, contaminated soils, and groundwater, with future advancements expected to enhance its efficiency and applicability. From the second perspective, recent advancements in IoT, AI, and biosensors are explored for their potential to revolutionize bioremediation and waste management. IoT facilitates real-time monitoring and remote management, AI enhances data analysis and predictive modelling, and biosensors contribute to precise pollutant detection and environmental monitoring. The review highlights the synergistic integration of these technologies, presenting smart bioremediation systems with real-time feedback loops and adaptive capabilities. Together, these technologies offer scalable solutions for environmental pollution mitigation, marking a significant stride towards sustainable environmental management.

Ezeh Ernest Mbamalu, Isah Yakub Mohammed

This study explored the co-valorisation of cassava peel and rice husk into biofuel precursors through pyrolysis. The research involved characterization of the biomass, and thermogravimetric analysis at heating rates of 5, 10, and 15 °C/min. An intermediate pyrolysis was conducted using a laboratory-scale setup with a stainless-steel reactor and a Swagelok double-ended tube, yielding pyrolytic oil for analysis. Proximate analysis revealed cassava peel (CP) contains 9.23 wt% ash, while rice husk (RH) has 16.50 wt% ash respectively, while the combined samples of cassava peel and rice husk (CS) had ash content of 74.27 wt%, fixed carbon of 70.07 wt%, and volatile matter of 75.72 wt%. The heating values for the samples were 17.15 MJ/kg, 15.22 MJ/kg, and 17.06 MJ/kg for cassava peel, rice husk, and combined sample respectively. Ultimate analysis indicated the following elemental compositions: CP (40.95 % C, 5.67 % H, 0.22 % N, 0.09 % S, 52.17 % O2), RH (40.15 % C, 5.98 % H, 0.41 % N, 0.78 % S, 52.68 % O2), and the CS (43.06 % C, 6.41 % H, 0.32 % N, 0.41 % S, 49.80 % O2). Kinetic and thermodynamic analysis from the distributed activation energy models revealed average activation energies of 184.95 kJ/mol (CP), 140.56 kJ/mol (RH), and 125.63 kJ/mol (CS). The pyrolysis products consist of 37.50 wt% pyrolytic oil, 11.12 wt% bio-char, and 51.38 wt% non-condensable gases. GC–MS analysis of the pyrolytic oil identified significant amounts of hydrocarbons, phenols, and phenol derivatives, suggesting potential for biofuel production. This study highlights the viability of combined biomass sources for biofuel production and waste to wealth utilization.

Asankha Pallegedara, Ajantha Sisira Kumara, D.M. Jayasena et al.

This randomized control trial (RCT) investigated the effectiveness of implementing two low-cost policy interventions to induce household members’ behaviour towards waste generation, waste segregation, and neighbourhood cleanliness in Dambulla local government area, Sri Lanka. After a baseline survey, as the intervention 1, only information leaflets containing instructions on household waste management were distributed among randomly-selected 93 households. As the intervention 2, each of another randomly-selected 96 households was provided with the leaflets along with a standard set of garbage bins consisting of three bins in three different colours: green bin for bio-degradable food waste; blue bin for paper waste; and orange bin for plastic and polythene waste. We keep another randomly-selected 92 households as the control group. The endline survey was conducted after a 12-week experimental period and treatment-effects of each policy intervention on outcome variables are estimated. The results reveal that even only with the provision of information leaflets, the households’ likelihood of segregating their waste into three categories can significantly be increased (by 17%, on average). The provision of three garbage bins along with leaflets has improved waste segregation behaviour of households substantially (by 36%, on average). However, neither intervention was successful in reducing household waste generation and improving neighbourhood cleanliness.

Sushant Sharma, S.K. Sharma, Sanigdha Acharya et al.

The present study investigates Direct Violet-35 (DV-35) remediation using electrocoagulation process. DV-35 which is an industrial azo dye, after release significantly affects the visual appearance of water bodies and hinders the process of photosynthesis affecting plant growth. Perturbing the food chain, it promotes toxicity, mutagenicity, and carcinogenicity. Therefore, dye remediation is essential before discharge into water streams. To determine the effectiveness of the electrocoagulation process for DV-35 dye remediation, and understand the influence of parameters like current density, inter-electrode spacing, concentration of electrolyte, pH, agitation speed, and initial dye concentration, a detailed study was carried out. Maximum removal efficiency (>98 %) was achieved in 16 min at 263.15 A/m2 current density and pH 7.2 for DV-35 concentration of 50 to 500 mg/L. Further, optimized parameters were applied to real textile effluent achieving 99.8 % efficiency. EC mechanism was corroborated by Sips isotherm matching adequately with experimental results. The findings also demonstrated a heterogeneous surface of the produced EC flocs. Pseudo-second-order was obtained with a low operating cost of 0.0018 US $/m3. The DV-35 removal and functional groups were confirmed by UV/VIS and Fourier transforms infrared spectroscopy analysis. The sludge was examined by X-ray Diffraction and Scanning Electron Microscope revealing Crystalline aluminum oxides i.e. bayerite (Al(OH)3) and diaspore (AlO(OH)). The conclusion of the results revealed EC to be an effective and economical technique for DV-35 remediation from textile wastewater.

T.A.N.T. Perera, H.A.T.N. Perera, D.M.N.A. Dissanayake et al.

The livestock sector’s emission of greenhouse gases and hazardous gases, has contributed significantly to environmental pollution, including climate change and global warming. Furthermore, the accumulation of microbial pathogens in livestock waste, including Salmonella and Escherichia coli, poses a risk to food safety and health. Several strategic solutions have been developed to control these impacts, ensuring compliance with environmental regulations and industry sustainability. UV irradiation has emerged as an effective technology in controlling emissions from the livestock sector, based on photolysis and photo-catalysis. A laboratory experiments prove that using UV in combination with filtration, the removal rate of CO2, NH3, N2O, VOC, pathogenic bacteria, and dust is 3.8 – 4.4%, 2.6–18.07%, 6.9 – 12.2%, 80 – 100%, 99.4%, and 95% respectively. Although photo-catalysis is highly effective in the elimination of gaseous compounds and pathogen, dust control is mainly done by filtration processes. This paper provides a comprehensive review of existing literature on global livestock emissions and pathogenic microorganisms, existing mitigation practices, UV treatment for livestock emissions mitigation, and the opportunities, challenges, and future perspectives and disinfection of common environmental pathogens of livestock emissions.

Md. Abul Hashem, Julkar Nayeen, Md. Tanvir Hossain et al.

The emitted wastewater from the tanning industry is extremely catastrophic and that contains a large extent of toxicants including heavy metals, especially chromium (Cr). Its detrimental effect increases due to its higher solubility and mobility in water. In this study, a thermally activated Borassus flabellifer (Palmyra palm) fruit shell was used to assess the removal of Cr from tannery wastewater. The biochar was characterized in terms of FT-IR, SEM micrograph, EDX, and pHpzc. FT-IR analysis represents the functional groups of the biochar, EDX illustrated the presence of elements in biochar, while the SEM micrograph revealed the adsorption through surface morphology. In batch adsorption, an optimum condition for maximum Cr removal was 3-g dose/50 mL wastewater for 10 min stirring time with a relative pH of 7.8. The adsorption mechanism was demonstrated through the pH and pHpzc values. This adsorption technique clarified 84.36 % Cr removal with a significant reduction of COD, Cl-, and BOD 88.07 %, 81.32 %, and 78.77 %, respectively. The relation between adsorbate and adsorbent was assessed by isotherm and kinetic models. The pseudo 2nd-order kinetics equation was well-fitted with a higher regression coefficient (R2 = 0.999). Besides, the Frenudlich model represented a stronger interaction between adsorbent and adsorbate (R2 = 0.9523) than the Langmuir model. Furthermore, this study revealed an innovative approach of utilizing Palmyra palm waste biomass as a thermally activated feasible adsorbent to remove Cr from industrial wastewater.

Oluwapelumi O. Ojuri, Ayodeji S. Olowoselu, Joshua Akinrele et al.

This study provides valuable insights into the waste composition, generation rates, and opportunities for improving the current solid management practices of a university campus in Sub-Saharan Africa. Representative points were selected within the campus to collect solid waste (SW). The SW were sampled following ASTM D5231-92. The quadrant method prescribed by ASTM D 6323 was used to reduce about 150 kg of collected waste to 50 kg. The SW samples were collected in triplicates and sorted manually to determine their composition. QGIS, a geographic information system was utilized to optimize waste collection efficiency, optimal collection points, and the number of waste bins. The average daily solid waste generation at FUTA was 952.3 kg, with polythene and paper waste constituting the largest proportions at 26 % and 24 %, respectively. The waste generation rate per capita was estimated at 0.046 kg per day. Remarkably, 81 % of the waste generated at FUTA has the potential for recycling. This offers a viable potential for promoting sustainable integrated solid waste management (SISWM). The study proposes optimising waste collection points from the initial 42 to 97, considering the proximity to buildings and transportation routes. The study did not consider fluctuations in waste generation rates and composition throughout the seasons, yet the data gathered is considered adequate for this initial survey. Lack of collaboration, adequate policies, funds, infrastructure, and political will are among the impediments to SISWM in FUTA. The introduction of colour-coded waste separation bins, and assigning different colours to specific waste types, can promote proper waste disposal and facilitate recycling. Also, engaging the university community through workshops and seminars can foster such behavioural change. Collaboration with local entrepreneurs and recycling centres is another essential aspect of this paradigm shift. Such partnerships can explore innovative solutions for upcycling polythene waste and create waste-to-wealth pathways. Initial challenges of an insufficient policy framework for university- small scale enterprises (SME) engagement and the lack of business growth models could be addressed by promoting relevant skill development and motivational tasking of the existing entrepreneurship faculty. By implementing the proposed strategies and embracing circular economy (CE) principles, FUTA can reduce its environmental impact, promote recycling, and foster a culture of sustainability and entrepreneurial value creation on campus and beyond.

Maitri Patel, M. Mansoor Ahammed

The use of reverse osmosis (RO) in urban wastewater treatment plants is becoming popular due to its efficiency in producing high-quality effluent suitable for various reuse applications. However, the process generates reverse osmosis concentrate (ROC) or reject as a byproduct, which poses significant environmental concerns. One of the primary issues with ROC is the presence of organic micropollutants (OMPs). These pollutants are found in substantial concentrations in reject water, raising concerns about their potential ecological and health impacts. This review provides a summary of the characteristics of ROC from urban wastewater treatment plants, focusing on the concentrations and types of OMPs present. The study shows that ROC contains a variety of dissolved organic compounds, dissolved ions, and organic micropollutants, making its treatment a challenge. The paper discusses various technologies studied for the removal of OMPs in ROC, including adsorption, advanced oxidation processes (AOPs), and other methods. Adsorption is identified as an effective method for the removal of OMPs, although some compounds show lower removal efficiencies. AOPs also have good removal capabilities but at the cost of forming potentially harmful byproducts. Emerging technologies such as forward osmosis combined with adsorption, constructed wetlands, and other microbial processes show promise but require further research for practicality. This paper thus underscores the necessity for continued innovation and optimization in ROC treatment methods to mitigate the adverse effects of OMPs on the environment and public health.

Radhika Sharma, Varinder Kumar

Conventional agriculture heavily relies on chemical compounds, adversely impacting health and ecosystem. Ensuring sustainable soil health necessitates the intelligent delivery of components to crop plants without any losses. Nanomaterials hold significant potential for enhancing agrochemical efficiency (50%), crop production (10–20%), and soil health. The nanomaterial improve different soil properties and its mechanism in soil and plant compartments, remains poorly understood. This review addresses critical questions regarding role of NMs in improving soil health, its mechanism and effects in the environment. Highlighting knowledge gaps, the article outlines essential areas for future research to ensure sustainable applications of nanotechnology in agriculture.

A. Mendoza, G. Kortaberria, D. Carrero et al.

The aim of this study is to evaluate the possibility of incorporating marine litter from the coast into the management system of the non-selectively collected fraction of Municipal Solid Waste (MSW). With this purpose, the technical feasibility of automatic separation of marine plastic litter is evaluated, which would allow for subsequent recycling. This solution requires mechanical–biological-treatment plants (MBT) to be able to sort marine plastic litter. Poly (ethylene terephthalate) (PET) bottles constitute one of the most commonly reported types of marine plastics. Considering the sorting methods employed in MBT plants, optical sorting tests were performed with marine PET litter and compared with those for post-consumer municipal PET waste, in order to assess whether the current technology implemented in these plants would allow their automatic sorting. Results show that the separation efficiency of PET degraded under marine conditions and outdoors is very high, and close to that of post-consumer municipal PET waste. The separation efficiency by transparent colour for different types of PET materials evaluated is also very effective and similar to that obtained for separation by chemical composition. Therefore, the chemical differences observed would not affect the efficiency of automatic sorting of marine origin PET in a waste treatment plant.

Rozina, Okezie Emmanuel, Mushtaq Ahmad et al.

Global interest in developing a state-of-the-art circular economy has been driven by the desire to generate bioenergy and bioproducts from biowaste streams. Biodiesel, synthesized from used, non-edible oils has emerged as a sustainable and ecofriendly alternative fuel for diesel engines. This study investigates the feasibility of employing an innovative circular economy to convert waste Citrus paradisi L. seed oil into sustainable biodiesel using green lead oxide nanoparticles (PbONPs). The synthesized biodiesel is noted for its ecofriendly characteristics, being non-toxic, biodegradable, cost effective and comparable to traditional petroleum-based diesel. PbONPs were prepared using aqueous leaf extract of Nasturtium officinale L. Analytical characterization of PbONPs revealed an average particle size of 42 nm. PbONPs demonstrated recyclability with maximum catalytic activity maintained through four consecutive cycles of transesterification. An optimal yield of 93 % was achieved under specific reaction conditions: a methanol-to-oil molar ratio of 7:1, a reaction time of 105 min, a temperature of 92.5 ˚C, and a catalyst load of 0.32 wt%. The predominant fatty acid methyl ester identified in the biodiesel was 5, 8-octadecadienoic acid methyl ester. The biodiesel produced from C. paradisi met the criteria for international standards with an impressively low sulfur content of 0.0001 %, underscoring its clean and benign nature.