Waste Disposal & Sustainable Energy最新文献

Chicken manure (CM) is one of the most common animal wastes produced worldwide. The conventional application of CM is as a fertilizer; however, in the present study, we introduce an approach for the straightforward and affordable use of CM for fuel cell applications. It reports the functionalization of carbon nanofibers (CNFs) using CM to confer multiple functionalities. The elements that make up the functionalized CNF are nitrogen (7.40%, atoms ratio, the same below), oxygen (6.22%), phosphorous (0.30%), and sulfur (0.02%), etc., according to energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy studies. It has been verified that following treatment with CM, the morphology of the CNFs remains the same. The CM-modified CNFs exhibit a higher electrocatalytic activity (onset potential: −0.0756 V; limiting current density: 2.69 mA/cm²) for the oxygen reduction reaction (ORR) at the cathode of a fuel cell. The electron transfer number for this sample is 3.68, i.e., the ORR favours a four-electron pathway like Pt/C. The direct method of functionalizing the CNF is more effective; however, treatment of CNFs with Triton X-100 prior to functionalization shields their otherwise exposed open edge sites and in turn affects their ORR activity. A large surface area (99.866 m²/g), the presence of multiple functional elements (oxygen, nitrogen, phosphorous, sulfur, etc.), surface charge redistribution and induced donor–acceptor interactions at the surface of CM-modified CNFs contribute to their enhanced electrochemical activity. This preliminary study reports the suitability of a facile and economical approach for treating CM for the most advanced clean energy applications. Hopefully, this study will pave the way for cutting-edge methods for handling other biowaste materials as well.

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Uneven heat dissipation will affect the reliability and performance attenuation of tram supercapacitor, and reducing the energy consumption of heat dissipation is also a problem that must be solved in supercapacitor engineering applications. This paper takes the vehicle supercapacitor energy storage power supply as the research object, and uses computational fluid dynamics (CFD) simulation to calculate its internal temperature distribution to solve the problem that the internal heat dissipation of the power supply in the initial design scheme is not uniform, and the maximum temperature of cell capacitors is as high as 67 °C. Filling of heat-conducting silicone film between single cell capacitors inside the module can conduct heat from single cell capacitor in the center of the module to the edge of the module quickly; adding baffles in the cabinet can optimize the air duct, and the temperature between the modules can be uniform; as a result of the combined effect of the two optimization measures, the maximum temperature of the cell capacitors drops to 55.5 °C, which is lower than the allowable operating temperature limit of the capacitor cell 56 °C. For the first time, the scheme of using air-conditioning waste exhaust air to cool supercapacitor energy storage power supply is proposed. Compared with the traditional cooling scheme using special air conditioning units, each energy storage system can save 967.16 kW·h per year using air-conditioning waste exhaust cooling, effectively reducing the overall energy consumption of the vehicle.

Food waste (FW) constitutes a significant portion of municipal solid waste (MSW) and represents an underutilized resource with substantial potential for energy generation. The effective management and recycling of FW are crucial for mitigating environmental issues and minimizing associated health risks. This comprehensive review provides an in-depth overview of current technological applications for converting FW into energy with the dual goals of reducing environmental impact and maximizing resource utilization. It covers various aspects, including pretreatment methods, biological technologies (e.g., anaerobic digestion and fermentation), and thermal technologies (e.g., incineration, pyrolysis, gasification, and hydrothermal carbonization). The analysis includes the scope, advantages and disadvantages of these techniques. Landfilling, composting, and incineration are widely considered the most prevalent methods of FW disposal and have substantial negative impacts on the environment. Advanced technologies such as anaerobic fermentation offer environmental benefits and are suitable for scaling up, reducing greenhouse gas emissions, and producing renewable energy such as biogas, thus reducing carbon emissions. The promotion and adoption of advanced technologies like anaerobic fermentation can contribute to more sustainable FW management practices, reduce environmental impacts, and support the transition to a circular economy. Additionally, this article presents successful case studies, emphasizing the importance of technological integration in FW treatment. Furthermore, this article outlines future directions for FW treatment, including advancements in biological treatment technologies, decentralized treatment systems, and the adoption of digital and data-driven FW management systems. These emerging trends aim to promote sustainable, resource-efficient, and environmentally responsible FW management practices.

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This review aims to synthesize previous literature with a focus on food loss or waste measurement, generation, causes, and impacts, including sustainable solutions. It has been estimated that the volume of food lost or wasted in five different food classes varies from production to consumption and differs greatly between low- and high-income countries. This study suggested certain mitigations to reduce food loss or waste in developed and developing countries. In the effective management of food loss or waste, a succession of solutions may be adopted and prioritized in a manner comparable to the waste management hierarchy. According to the food loss or waste hierarchy, the first and most desired action to prevent food waste is to minimize food surplus and unnecessary food waste. Food donation to low-income populations through food bank organizations or social sectors is the second most appealing alternative, and turning food waste into animal feed is the third most appealing option. The authors described accessing the environment, economic and social impact, and intervention to prevent or reduce food loss or waste. Reduced food loss or waste prevents the waste of land, water, energy, and other resources incorporated in food and is thus critical to enhancing food system sustainability. The sustainable approaches for food waste management were then discussed with detailed elaboration on the most commonly practiced disposal and recycling methods for product recovery, as well as industrial applications via thermal and chemical treatment. In conclusion, this paper presents the outlook of the overall framework and suggests an outline of future directions in this field.

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The surge in medical waste, fueled by the impact of COVID-19 and the influenza A virus, poses substantial challenges to waste treatment. Nevertheless, pyrolysis technology introduces a novel approach to the treatment of medical waste. This study investigated the pyrolytic characteristics, kinetics, thermodynamic parameters, volatile gases, and pyrolytic pathways of medical rubber gloves (MRGs) in a N₂ atmosphere utilizing Thermal Gravimetric Analyzer (TGA), Thermogravimetric-Fourier transform infrared spectroscopy (TG-FTIR) and Pyrolysis gas chrogams-mass spectrometry (Py-GC/MS) analyses. Pyrolysis of MRG predominantly occurs between 284–501 °C and 613–701 °C. The initial stage is the primary reaction phase, exhibiting an average activation energy of 339.77 kJ/mol, following the reaction order model (Fn). The second pyrolysis stage has an average activation energy of 236.93 kJ/mol and adheres to the geometric contraction model (Rn). The volatile products from MRG pyrolysis primarily comprise olefins, alkanes, and aromatic hydrocarbons. The olefins consist primarily of 1,2-pentadiene and d-limonene, while the alkanes include cyclopropane, cyclohexane, and 1,4-dimethyl. Aromatic compounds are chiefly benzene, toluene, and xylene.

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Due to competitive adsorption between CO₂ and H₂O, hydrogen evolution reaction reacts easily in the photothermal CO₂ reduction. Herein, the amphoteric oxide loaded on TiO₂ catalyst was prepared to enhance CO₂ adsorption as well as improve the photo-responsive properties. The samples with 10% mass fraction of ZnO loaded on TiO₂ exhibited the best photothermal catalytic performance. The average yields of H₂, CO and CH₄ were estimated to be 35.7, 43.5, and 5.7 μmol/(g·h), respectively. Also, the selectivity of carbon-containing products increased from 28.9% to 48.8% when compared to P25. The loading of amphoteric oxides can act as adsorption sites on the material surface to adsorb acidic molecules of CO₂ for reaction, improving the selectivity of carbon-containing products. In addition, amphoteric oxides are good semiconductors, which can improve the photo-responsive properties of the catalyst and form heterostructures with TiO₂ to promote the separation of photogenerated electron–hole pairs, allowing more photo-generated carriers to participate in the reaction. Finally, both functions including CO₂ adsorption and solar light absorption could be realized on the all-in-one amphoteric oxide loaded on TiO₂ component.

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As a low-value solid waste fuel, asphalt rock is prone to slagging even under fluidized bed condition. The purpose of this study is to improve the slagging characteristics of asphalt rock by adding the mineral additives CaCO₃, MgO, and Kaolin. The results showed that the K, Al, Ca salts in asphalt rock ash will evolve at different temperatures and exist mainly as K₂SO₄, KAlSiO₄, Al₂O₃·SiO₂, Al₂O₃, CaSO₄, and CaSiO₃. The CaSO₄ formed from sulfur oxides and calcium-containing compounds is the main factor in asphalt rock slagging and can be facilitated by CaSiO₃ with a small amount of CaCO₃. The MgO can form MgCa(SiO₃)₂ with a high melting point and helps raise the ash fusion temperatures. In addition, the Kaolin will promote the formation of low-temperature eutectics, resulting in a slight decrease in ash fusion temperatures. Through optimization, it was found that with the addition of 9.0% MgO+9.0% Kaolin+2.0% CaCO₃ (in weight), the slagging ratio and pressure difference of asphalt rock under fluidized bed conditions decreased from 6.5% to 4.2% and from 6.0 Pa to 4.0 Pa, respectively. By combining simulation and experimental methods, it has been shown that appropriate mineral additives of CaCO₃, MgO, and Kaolin can effectively improve the slagging characteristics of asphalt rock.

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The disposal of bone waste can be effectively addressed utilizing a novel approach involving the synthesis of a bovine bone-derived biochar-based Mg/Al-layered double hydroxide (LDH) nanocomposite (B-Mg/Al-NC). This nanocomposite exhibits exceptional capabilities for removing specific dyes, such as Methylene Blue (MB) and Congo Red (CR), from aqueous media. Extensive characterization using techniques confirmed the successful formation of the B-Mg/Al-NC, which possesses a high surface area, high porosity, and abundant functional groups. The Langmuir monolayer biosorption capacity was 395.56 mg g⁻¹ and 328.25 mg g⁻¹ at 50 °C for MB and CR, respectively, with rapid dye removal achieved within 25 min under alkaline pH conditions. The experimental data fit well with the pseudo-second-order kinetics model for both dyes. The remarkable dye adsorption capacity of the B-Mg/Al-NC can be attributed to the combined basic properties of the bone biochar and Mg/Al-LDH. Proposed mechanisms for enhanced dye removal include hydrogen bonding interactions, anion exchange, surface complexation, electrostatic interactions, and pore filling. Furthermore, the nanocomposite exhibited excellent reusability. In addition to its dye removal capabilities, the B-Mg/Al-NC was found to have a positive effect on seed germination and growth and salient soil health parameters, as demonstrated by a rapid seed germination test using the spent composite. Overall, the facile synthesis of the B-Mg/Al-NC via co-precipitation and ultrasonication is a highly recommended and sustainable approach for producing an eco-friendly bio-sorbent with exceptional dye removal efficiency from wastewater while also addressing the issue of bone waste disposal.

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Graphene/semiconductor heterojunction anodes can significantly enhance the output voltage by the photovoltaic effect. However, a significant challenge arises from the high intrinsic work function of heterojunction surfaces, which limits efficient electron emission. In this study, we explored the potential of low work function materials modified by Cs/Cs-O adsorption as anodes for thermionic (TI) converters through first principles calculations. The results demonstrate that the work functions of the graphene/MoS₂ and the graphene/n-type Si surfaces with only Cs coating can decrease to 1.48 eV and 2.46 eV, respectively. The multiple Cs-O atoms co-adsorption enhances the dipole moment, resulting in a further reduction of the work function of the graphene/MoS₂ surface to 1.25 eV. In addition, the impact of work function on the performance of TI converters is revealed by using concentrated solar energy as heat source. The highest conversion efficiency achieves 15.25% for the Cs-4O: Gr/MoS₂ anode. This study establishes a robust foundation for further advancement of the TI converters with graphene/semiconductor heterojunction anodes.

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There are many applications for the technology of producing hydrogen from organic waste. Due to its large volume, high organic content, and stable source, sewage sludge has gained significant attention among various organic wastes. The purpose of this paper is to present a bibliometric and technological study of hydrogen production from anaerobic fermentation of sewage sludge during the last decade using data from the Web of Science. The analysis of authors, countries/regions, and keywords is the primary focus of the bibliometric study. In terms of technological advances, this paper reviews the mechanisms and influencing factors of hydrogen production from sewage sludge, and provides an overview of the research on pretreatment and co-fermentation that has been carried out in recent years to improve the hydrogen production rate. This paper discusses the challenges faced in anaerobic hydrogen production from sludge and concludes that more research is needed for its commercialization and large-scale application. This review provides references and ideas for sludge synergies in the utilization of organic solid waste resources.

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