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Buckwheat husks are a valuable source of carbon and show the potential to be used as an energy source. However, due to low bulk density and low susceptibility to compaction, it is beneficial to use them in the form of co-pellets. The study presents comprehensive research detailing buckwheat husks' potential for co-pelletization with oily (peanut husks) and dusty (senna leaves) agri-food wastes, whereas the effect of material parameters such as the amount of additive (10, 15, 20%) and the process parameters as the die rotational speed (170, 220, 270 rpm) on pellets' quality (kinetic durability, bulk and particle density, degree of compaction) and the energy consumption of the pelletization process were examined. Ten percent of potato pulp as a binder was added to each pelletized mixture. It was found that an increase in the senna leaf content affects positively the kinetic durability of pellets. The fatty peanut husks have a negative effect on the pellets' quality (measured by the kinetic durability and bulk density); however, both additions of senna leaves and peanut husks are lowering the energy consumption of the pelletizer. The highest quality pellets and the addition of 10% peanut husks to buckwheat husks (kinetic durability of 96%) and 20% of senna leaves to buckwheat husks (kinetic durability of 92%) obtained at 170 rpm were subjected to combustion in a fixed-bed unit, and the content of CO, CO2, NO, SO2, HCl, and O2 in the fuel gases was measured. The emission factors were higher than the Ecodesign limitations (CO > 500 mg·Nm−3, NO > 200 mg·Nm−3). The obtained results indicate that buckwheat husks can be successfully co-pelletized with other waste biomass; however, the pellets to be combusted require a boiler with improved air-supplying construction. [ABSTRACT FROM AUTHOR]

Torrefaction was applied to enhance the fuel properties of sawdust (SD) and bark wood (BW), biomass wastes from the rubberwood processing industry. Design Expert (DE) software was used in an experimental design to study the effects of affecting factors including torrefaction temperature and time as well as the biomass size towards the desirable properties such as HHV, mass yield, fixed carbon content, and eco-efficiency values. Promising results showed that the HHVs of the torrefied SD (25 MJ/kg) and BW (26 MJ/kg) were significantly increased when compared to preheated SD (17 MJ/kg) and preheated BW (17 MJ/kg) and in a range similar to that of coal (25–35 MJ/kg). The TGA, FTIR, biomass compositions, and O/C ratios suggested that thermochemical reactions played a significant role in the torrefaction at which thermal degradation coupled with possible in situ chemical reactions took place, to some extent. The optimal conditions of the torrefaction were identified at 320 °C and 30 min for SD, and 325 °C and 30 min for BW. The maximum HHVs at the optimal condition were 22, 23, and 20 MJ/kg while the eco-efficiency values were 29.18, 27.89, and 13.72 kJ/kg CO2_eq*THB for torrefied SD, torrefied BW, and coal, respectively. The findings of this study indicate that torrefied rubberwood residues enhanced HHV, eco-efficiency, and less contribution to CO2 emissions compared to fossil fuels. [ABSTRACT FROM AUTHOR]

Waste-to-energy technologies from anaerobic digestion (WtE-DA) are successfully used in European countries for electricity generation. In Mexico, the application of these processes is limited due to their design and operation complexity, high required investment, high operations and maintenance costs, and low government support, which hinders their economic competitiveness. This work conducted a study to determine the best conditions of electricity generation through WtE-DA processes to be competitive compared with the conventional process. An industrial-scale process was designed regarding the co-digestion of fruit and vegetable waste from a food supply center with slaughterhouse waste from the Monterrey Metropolitan Area in Mexico. Analysis scenarios were strategically proposed considering different sizes of the WtE-DA plant, transport distance from the source of waste to the process, and the degree of government participation through economic subsidies granted to clean energy production. The environmental performance of the plant was evaluated via the climate change indicator (CCI) following a life cycle analysis approach, and the net present value (NPV) was used as an economic criterion. The results show that the CCI has a high sensitivity to the waste transport distance, having a maximum of 130 km to ensure environmental success. The sensitivity analysis performed on the management capacity and NPV indicates that plants smaller than 72,000 t year−1 are economically unviable and require governmental financial support like that granted in European countries. This work provides reliable operating, eco-efficiency criteria, and subsidy schemes to support decision-making for proper investment in bioenergy projects. [ABSTRACT FROM AUTHOR]

Pollution and the rising energy demand are two major society issues, requiring urgent solutions. Here, we review the simultaneous production of hydrogen and removal of pollutants, with a focus on mechanisms, synthesis of photocatalysts, and applications. Remarkably, this method utilizes organic pollutants as sacrificial agents for photocatalytic hydrogen production, thus both reducing pollution and producing energy. Metal-doped, cocatalyst-loaded, organic and inorganic composite, heterostructure and heterojunction photocatalysts are described. We present applications to the removal of antibiotics and organic dyes. Pollutant degradation rates range from 5.3 to 100%, with hydrogen evolution of 13.7–2724.89 μmol·g–1h–1. [ABSTRACT FROM AUTHOR]

This study proposes a simplified unit that can be employed in an industrial facility for the utilization of its own abundant plastic waste, primarily from discarded packaging, to achieve full or partial energy autonomy. By converting this waste into synthetic pyrolysis oil equivalent to 91,500 L, the industry can power a combined heat and power generation unit. The proposed unit was designed with a focus on maintaining high temperatures efficiently while minimizing oxygen exposure to protect the integrity of hydrocarbons until they transform into new compounds. Pyrolysis stands as a foundational procedure, paving the way for subsequent thermochemical transformations such as combustion and gasification. This study delves into the factors affecting pyrolysis and presents analytically the mathematical formulations and relevant calculations in order to effectively design and apply a real-life system. On this basis, fuels from plastic waste can be produced, suitable for utilization in typical equipment meant to produce heat, estimated for six months' operation and 800 MWh of electricity. This study enhances the transition towards a more circular and resource-efficient economy with technologies that unlock the latent energy contained within the discarded matter. Additionally, it demonstrates the feasibility of a moderate investment in a co-generation system for industries utilizing 568 tonnes of plastic waste per year. The design and accurate calculations of this study highlight the theoretical potential of this technology, promoting environmental sustainability and resource conservation. [ABSTRACT FROM AUTHOR]

This review examines the potential of municipal solid waste (MSW) as a renewable energy source, focusing on recent advances in thermochemical conversion technologies and their environmental impacts. The exponential growth of urban populations has led to a surge in MSW, necessitating sustainable waste management solutions. Traditional disposal methods, such as landfilling and incineration, have significant environmental drawbacks. However, advancements in waste-to-energy (WtE) technologies, including incineration, pyrolysis, and gasification, offer promising alternatives for energy recovery and resource utilization. This review explores the composition of MSW, its classification as a renewable resource, and the thermochemical conversion technologies that transform waste into energy. The environmental impacts of these technologies, particularly emissions and air quality concerns, are critically analyzed. The review highlights the evolving regulatory landscape and the implementation of advanced emission reduction systems. The findings underscore the importance of integrating innovative waste management strategies to promote a circular economy and achieve sustainable development goals. [ABSTRACT FROM AUTHOR]

The present study highlights the dual benefits of landfill gas utilization:mitigating greenhouse gas emissions and generating renewable energy. Municipal waste, containing a large proportion of organic matter, is dumped into Solid Waste Disposal Sites (SWDS), which, after anaerobic decomposition, releases methane (CH4). This study aims to assess the methane emissions from the SWDS of Chandigarh, India, and evaluate the potential for electricity generation from captured landfill gas. Waste samples were obtained using the quartile method and examined for proximate and ultimate analysis. The inventory and estimation of CH4 generation were done using the International Panel on Climate Change (IPCC) methodology, including the potential of electricity generation from the CH4 generated. It has been observed that Chandigarh generates around 350 tons per day (TPD) of waste, with organic material constituting over 50% on average. The estimated amount of municipal waste with observed composition led to the generation of 0.34 Gg/yr of CH4. Depending on the efficiency of the gas energy system, 0.27 MW to 0.77 MW of electric power can be produced in Chandigarh. The study also provides a broader context for solid waste management in India. Analysis of national data revealed that India generates about 160,038.9 TPD of solid waste, with only about half (79,956.3 TPD) being treated. The country has 3,184 existing dumpsites, with significant variations across states. As per the present analysis, when extrapolated to a national scale, India could potentially generate 5,167 MWto 14,355 MWof power fromall its SWDS, resulting in annual financial gains of 4.7 to 13 billion USD. These findings underscore the importance of implementing integrated waste management strategies that prioritize waste reduction, efficient treatment, and energy recovery from landfill gas. [ABSTRACT FROM AUTHOR]

Ghana Tamale's current waste management system is overwhelmed by the growing waste crisis, necessitating the exploration of Waste-to-Energy technologies (WtE) as an innovative solution. This study explores challenges and opportunities for integrating WtE technologies into Tamale's existing waste management system. Qualitative research identified policy hurdles, financial constraints, social concerns, and institutional weaknesses as key barriers. Conversely, stakeholder collaboration, public education, and capacity building emerged as some success factors. A proposed implementation plan emphasizes feasibility studies, public engagement, public–private partnerships (PPPs), and technology selection based on waste composition. Additionally, a novel framework for WtE integration within a broader Integrated Solid Waste Management (ISWM) system is presented. This framework incorporates waste sorting, recycling, WtE alternatives, and responsible management of residuals. Validation by key stakeholders confirmed the framework's potential to improve waste management in Tamale. By overcoming identified challenges and implementing the proposed framework, Tamale can achieve environmental sustainability, energy generation, and progress towards UN SDGs 7, 11, and 12. This research offers valuable insights for policymakers and paves the way for a cleaner and more sustainable future for Tamale, potentially serving as a model for other developing cities. [ABSTRACT FROM AUTHOR]

Energy sources all around the world are degrading at a rapid pace. The exponential rise in population, along with urbanization, requires exploration and advancement in diverse fuel resources. Municipal solid waste (MSW) disposal requires urgent intervention in terms of its utilization and conversion into useful energy forms than being dumped into landfills. Though efforts are being made for its combustion in furnaces, the plastic contents in RDF often pose environmental concerns when used for combustion. The gasification process has been explored for the effective processing of different forms of waste in the present study. The composition of MSW varies widely with demography, weather, and habitats. In the present study, MSW of Surat metropolitan city of India is processed post collection, through sorting, segregation, and compaction, and transformed to fuel, which is termed as refuse-derived fuel (RDF). A chemical representation of the RDF is used to perform gasification studies with the help of two thermodynamic equilibrium models. Parametric analysis of the gasification models is performed to analyze the effect of equivalence ratio and gasification reaction temperatures on the product gas composition for the prepared composition of RDF. Results reveal that the combined equilibrium model is more accurate in predicting product gas composition compared to the Homogeneous model. It is observed that the variation of the equivalence ratio has a more significant influence on the product gas composition than the variation in the gasification temperature. The study concludes that RDF from MSW may be efficiently transformed into useful gaseous fuel through gasification resulting in product gas with a calorific value of approximately 25 MJ per kg of RDF gasified. [ABSTRACT FROM AUTHOR]

Pressure to increase the renewable energy matrix motivates the search for new energy sources. Pulp and paper mills have been constantly expanding in Brazil, and to ensure their competitiveness, new processes should be established both in terms of reducing the waste discarded in landfills, as well as the substitution of fossil fuels used in the mills. The present work aims to evaluate the energy potential of primary sludge (PS), secondary sludge (SS), a mixture of primary and secondary sludge (MS) and tree bark (B) generated in a Brazilian TMP mill. Characterization of all biomasses was performed. Moisture content, higher, lower, and net heating value, elemental, structural, and immediate composition, thermogravimetric analysis and quantification of minerals and metals were determined The bark presented the highest higher heating value (HHV) (18.90 MJ kg−1), while the secondary sludge had the lowest HHV (12.45 MJ kg−1). The high concentration of ash in the sludges PS (26.58%), SS (40.46%) and MS (25.78%) negatively affected their heating value. The sludges also showed high moisture content, which made their burning without a previous drying stage unattractive. Nevertheless, the sludges and the bark are rich in carbon which makes them attractive for use as biomasses for energy generation. [ABSTRACT FROM AUTHOR]

This study aims to design the onboard waste-to-energy process to dispose waste plastic debris floating in the ocean. Collected marine debris undergoes pretreatment such as freezing and pulverization process. The pretreated plastic waste is transformed into hydrogen through plasma gasification, separation and purification which finally produces electricity by fuel-cell system. The hydrogen separation and purification process consist of water gas shift reaction and pressure swing adsorption process. Lab-scale experiments for the separation and purification process were carried out as a preliminary study prior to designing a practical scale integrated system. For low-temperature water gas shift, Cu–Zn–Al catalyst calcined under nitrogen atmosphere outperformed typical commercial catalysts. Process simulations indicate the need of additional apparatus such as heat exchanger, dehumidifier, and compressor for practical operation of the combined waste-to-energy process. Practical operation window based on the deviation between the ideal performance obtained from simulations and the measured performance from experiments was discussed. [ABSTRACT FROM AUTHOR]

Production of green energy from landfill gas in a cogeneration system is considered optimal in terms of the use of local renewable energy resources, which in the production process generates hazardous waste. Yet, the production of renewable energy is not without environmental effects. The objective of the work was to analyse the operation of the installation for biogas energy generated at a municipal waste landfill and to carry out tests on the waste (mineral deposit) from a heat exchanger generated in the exhaust manifold of a gas engine of the cogeneration unit. The objective of the work was to test waste (mineral deposit) from the heat exchanger in the exhaust manifold of the gas engine of the cogeneration unit. The conducted research constitutes a significant contribution to the identification and classification of hazardous waste generated in a cogeneration unit powered by landfill gas. The results of the research showed that the waste contains high concentrations of ecotoxic elements, i.e. heavy metals (arsenic, chromium, copper, nickel, zinc), molybdenum, antimony, sulphates, which have carcinogenic activity. Pioneering research performed as part of the leaching test showed that the permissible concentrations were exceeded for 11 parameters in the case of storage in a hazardous waste landfill, and for 6 parameters in the case of storage in an underground hazardous waste landfill. The research and analyses performed in this work will serve as input material for defining the methods of hazardous waste disposal from the cogeneration unit. [ABSTRACT FROM AUTHOR]

The Brazilian Policy foresees the waste management hierarchy, according to which energy reuse from waste is preferred to final disposal. However, less than 0.2% of the country's waste goes to energy production. This paper proposes sustainability indicators to support the decision to choose the best process to treat municipal solid waste (MSW) through bioenergy generation technologies. Then, we conduct a case study for Rio de Janeiro. Incineration and gasification were not economically feasible—despite TRL 9 and 8. However, the projects presented a null net present value by increasing the gate fee to 94.69 and 255.39 USD/ton of MSW, respectively. The social indicators (job creation, salary increase with the absorption of waste pickers, population served, reduction in MSW sent to landfill) did not indicate the best technology. The results of the environmental indicators for incineration and gasification were, respectively, 0.45 and 0.37 t CO2eq/tMSW for GWP, 1.49 and 1.23 MWh/tMSW for energy intensity, 1.24 and 6.14 m3/tMSW for water intensity, 39.3 and 27.9 m2/tMSW for land use and 0.135 and 0.088 t SO2eq/tMSW for acidification. Gasification presented better results on 60% of the environmental indicators. However, incineration scored better in the important ones, water and energy intensities, in addition to the technical–economic aspect. [ABSTRACT FROM AUTHOR]

Abstract Waste and energy sectors have significant contributions to the greenhouse gas (GHG) emissions caused primarily by the population expansion. Waste-to-Energy (WtE) is introduced to address the issue raised by both sectors simultaneously through utilization of the potential energy stored in municipal solid waste (MSW) as well as offsetting GHG emissions. Limited research have been conducted in Egypt to assess the current situation of MSW management and associated methane emissions. The current study focused on estimating the baseline methane emissions for six Egyptian governorates and determining the energy production potential from WtE projects. To achieve this aim, three scenarios have been assessed: Baseline, Landfill Gas to Energy (LFGE), and Incineration scenarios. Key results revealed that a total of 3.7 million tonnes of methane would be emitted from all studied governorates generated over 50 years. Incineration also found to be more favorable in all governorates in terms of energy production, quantity of avoided GHG emissions, and in terms of economic viability over LFGE. Implementing incineration in all governorates would generate about 5.6 TWh energy annually and could avoid about 5 Mt CO2 eq annually in comparison to LFGE that would generate about 0.6 TWh annually and could avoid about 2.5 Mt CO2 eq annually. In terms of economic viability of WtE projects, while they were generally not economically viable under the assumptions made in the current study, incineration technology deemed promising, but policy adjustments, such as competitive Feed-in Tariff (FiT) rates and the inclusion of gate fees, are necessary. Specific minimum gate fees and FiT were identified for each governorate, providing essential guidance for decision makers to ensure the viability of WtE implementation. This study would support the decision makers in assessing technically and financially feasible options for WtE technologies in the selected governorates.

Ghana Tamale’s current waste management system is overwhelmed by the growing waste crisis, necessitating the exploration of Waste-to-Energy technologies (WtE) as an innovative solution. This study explores challenges and opportunities for integrating WtE technologies into Tamale’s existing waste management system. Qualitative research identified policy hurdles, financial constraints, social concerns, and institutional weaknesses as key barriers. Conversely, stakeholder collaboration, public education, and capacity building emerged as some success factors. A proposed implementation plan emphasizes feasibility studies, public engagement, public–private partnerships (PPPs), and technology selection based on waste composition. Additionally, a novel framework for WtE integration within a broader Integrated Solid Waste Management (ISWM) system is presented. This framework incorporates waste sorting, recycling, WtE alternatives, and responsible management of residuals. Validation by key stakeholders confirmed the framework’s potential to improve waste management in Tamale. By overcoming identified challenges and implementing the proposed framework, Tamale can achieve environmental sustainability, energy generation, and progress towards UN SDGs 7, 11, and 12. This research offers valuable insights for policymakers and paves the way for a cleaner and more sustainable future for Tamale, potentially serving as a model for other developing cities.

Abstract Petroleum fuels are commonly used for automobiles. However, the continuous depletion and exhaust gas emission causes serious problems. So, there is a need for an alternative eco-friendly fuel. Biodiesel is a type of fuel manufactured through a process called transesterification, which involves converting vegetable oils into a usable form. The process parameters of the transesterification process were optimized using the Taguchi method to achieve maximum biodiesel yield. However, the main problem of biodiesel is its high cost which could be reduced by using low-cost feedstock. To address this challenge, biodiesel (BCFAD) is derived from coconut fatty acid distillate (CFAD), a by-product obtained from refining coconut oil. This work uses BCFAD and BCFAD with Alumina nanoparticles as fuels. Alumina nanoparticles in the mass fraction of 25 ppm, 50 ppm, and 100 ppm are dispersed in BCFAD. The investigation results reveal an increase of 6.5% in brake thermal efficiency for BCFAD with 100 ppm nanoparticles when compared to BCFAD. There is a reduction of 29.29% of hydrocarbon and 34% of Carbon monoxide emissions with BCFAD100 in comparison with diesel. However, there is a marginal increase in NOx emission with the increase in nanoparticles. The heat release rate and cylinder pressure of BCFAD100 are comparable to diesel fuel. It was concluded that the utilization of BCFAD with a nanoparticle dispersion of 100 ppm is suitable for direct use as fuel in diesel engines.

Circular economy and sustainability are pivotal concepts in the discourse on the synergies between economic growth and environmental impact. As resource scarcity and environmental degradation intensify, advancements in energy conversion technologies become crucial for a sustainable economic model. Currently dependent on fossil fuels, the global economy must shift to a sustainable framework focused on bioenergy. Biomass, a renewable energy source, offers a promising solution by converting waste into valuable resources, reducing waste and environmental impact, and creating economic opportunities. Biofuels and bioproducts can meet energy needs while reducing greenhouse gas emissions and addressing global warming. Recent advances in biofuels, supported by initiatives and policies, promote more sustainable energy production. This paper aims to highlight the potential of biomass in meeting contemporary energy demand and provides an overview of biofuels and their production as a renewable alternative to fossil fuels. It also explores the future of agriculture and energy sectors, emphasizing global energy and environmental challenges and the competition between food and fuel feedstocks. [ABSTRACT FROM AUTHOR]

Organic waste-to-energy (OWtE) technologies are playing a steadily increasing role in the Green Transition, thus becoming a powerful driver in the establishment of an ever more efficient and sustainable circular economy. The advantages of OWtE processes are well known: not only do they reduce the waste volumes sent to landfills or incineration plants, but also and foremost, through the energy they yield (biogenic carbon dioxide, amongst others), they reduce dependance on fossil fuels. This article gives a complete panorama of these technologies, starting from the classical methods and ending with a review of the latest modern novelties. Advantages and disadvantages of each method are highlighted, with particular focus on the formation of by-products and the relevant treatment aimed at preventing environmental pollution. Accordingly, modern techniques for increasing waste-to-energy efficiency and integrating the concept of circular economy and substitutability are analyzed from this perspective. Along with an analysis of modern scientific achievements in this area, practical examples of the implementation of technologies in European countries are given, with an emphasis on the obvious advantages, both economic and environmental. [ABSTRACT FROM AUTHOR]

The disposal of wood waste at facilities for incineration in Sweden is the only applied management practice today. Energy production from biomass has gained attention for its potential to recover energy and reduce greenhouse gas emissions. However, besides being a valuable source for energy generation, wood waste can be effectively recycled into new products. Specifically, recycling wood waste into particleboard is the widely practiced method in Europe, while its benefits have not been explored in the country so far. The objective of this study is to assess the environmental, social, and economic sustainability of producing particleboard and generating energy from wood waste in Sweden. This research investigates four alternative systems for wood waste disposal. The first system involves the production of heat, the second system involves heat and power by wood waste, while the third and the fourth systems, in addition to energy recovery, include partial recycling of wood waste in particleboard production. A life cycle sustainability assessment covering all three pillars (environment, social, and economic) of sustainability was conducted to compare these systems. The results show that adding recycling schemes to incineration in wood waste management practices strengthens the sustainability for all three aspects, and hence, these management methods can be considered as complementary methods rather than competing methods. When all sustainability categories are considered, alternative three (heat recovery and recycling) comes forward as the best option in 11 out of 16 impact categories. [ABSTRACT FROM AUTHOR]

The adoption of biofuels as an energy source has experienced a substantial increase, exceeding the consumption of fossil fuels. The shift can be ascribed to the availability of renewable resources for energy production and the ecological advantages linked to their utilisation. Nevertheless, due to its intricate characteristics, the process of producing ethanol fuel from biomass poses difficulties in terms of administration, enhancement, and forecasting future results. To tackle these difficulties, it is crucial to utilise modelling techniques like artificial intelligence (AI) to create, oversee, and improve bioethanol production procedures. Artificial Neural Networks (ANN) is a prominent AI technique that offers significant advantages for modelling bioethanol production systems' pretreatment, fermentation, and conversion stages. They are highly flexible and accurate, making them particularly well-suited. This study thoroughly examines several artificial intelligence techniques used in bioethanol production, specifically focusing on research published in the past ten years. The analysis emphasises the importance of using AI methods to address the complexities of bioethanol production and shows their role in enhancing efficiency and sustainability in the biofuel industry. [ABSTRACT FROM AUTHOR]

Waste incineration with energy recovery is a matured Waste-to-Energy (WtE) technology which has contributed immensely to the disposal and management of Municipal Solid Waste (MSW) in industrialised nations. The adoption of this technology in developing countries is currently gaining momentum due to the numerous benefits that can be derived from its use. In this study, a techno-economic assessment of MSW incineration in proposed waste incineration facilities for use in Ghana was carried out. The technical assessment was conducted by determining the plant capacity and annual electricity production based on the combustible residues of MSW collected from various population sizes in the country, while the economic assessment was carried out by determining two key economic indicators, Net Present Value (NPV) and Levelised Cost of Energy (LCOE). It was found that a total of about 400 MW of electricity can be generated from the total of about 14,000 tonnes of MSW generated in the country daily. The NPV for a 35.81 MW installed capacity of waste incineration facility was found to be USD 166,410,969.24. However, the LCOE for the 35.81 MW capacity and all others considered was greater than the tariff of electricity for their respective capacities, which means waste incineration facilities are not economically viable ventures in Ghana. The implementation of these facilities in the country would, therefore, need governmental support in the form of subsidies and tax rebates. Three locations were proposed for the piloting of waste incineration facilities in the country, and these locations are in the Accra Metropolitan, Asokore-Mampong Metropolitan, and Sekondi-Takoradi Metropolitan Assemblies. [ABSTRACT FROM AUTHOR]

This study investigated the effects of different proportions of waste polyethylene (WP) and waste cooking oil (WCO) on the chemical and physical properties of the resulting co‐pyrolysis oil produced in an indigenously developed laboratory‐scale fixed bed batch‐type reactor. The proportion of WCO was altered in increments of 10% from 10% to 90%, and correspondingly, the proportion of WP was adjusted from 90% to 10% (by weight). The highest liquid fuel yield, reaching 70.9% by weight, was achieved using a 40:60 ratio of WCO to WP (W40P60) at a constant heating rate of 12°C and a temperature of 500°C. The obtained fuel exhibits promising properties, including a high calorific value (max HHV around 45.63 MJ/kg) and other advantageous properties such as low viscosity, low oxygen and nitrogen content, and absence of sulfur. Fourier‐transform infrared spectroscopy (FTIR) and gas chromatography–mass spectroscopy (GCMS) were examined on the resulting liquid fuel. The GC–MS spectra predominantly display alkanes, constituting approximately 41% by weight, and alkenes, making up roughly 20% by weight. These analyses revealed properties akin to commercial diesel, emphasizing the potential of waste cooking oil and waste polyethylene proportions in liquid diesel like fuel production. [ABSTRACT FROM AUTHOR]

This paper puts forward a generic methodological framework to holistically assess WtE technologies based on the PROMETHEE approach. In addition to environmental and economic aspects, the method focuses on large-scale applicability and social preference, thus adopting economic, environmental, social, and technological criteria. Three data sources are selected, namely the scientific literature, a public survey, and an experts' opinion survey, which is a novel combination with the aim to cover public consensus, technological applicability, and to provide alternative data sources for the economic and environmental criteria, thus enriching the methodology with the input of location specific data. The demonstration of the applicability of the proposed methodology is realized at a national level for the case of Greece. Anaerobic Digestion is shown to be the most preferable choice, recognized for its cost-effectiveness and lower environmental burden to other WtE technologies (i.e., gasification, pyrolysis, incineration). When all criteria are evaluated with equal weights, anaerobic digestion greatly outperforms incineration (net flow 0.833 versus 0.1667), while incineration only becomes the most preferred choice if the social criterion is in high focus (i.e., over 63% weight). [ABSTRACT FROM AUTHOR]

Petroleum fuels are commonly used for automobiles. However, the continuous depletion and exhaust gas emission causes serious problems. So, there is a need for an alternative eco-friendly fuel. Biodiesel is a type of fuel manufactured through a process called transesterification, which involves converting vegetable oils into a usable form. The process parameters of the transesterification process were optimized using the Taguchi method to achieve maximum biodiesel yield. However, the main problem of biodiesel is its high cost which could be reduced by using low-cost feedstock. To address this challenge, biodiesel (BCFAD) is derived from coconut fatty acid distillate (CFAD), a by-product obtained from refining coconut oil. This work uses BCFAD and BCFAD with Alumina nanoparticles as fuels. Alumina nanoparticles in the mass fraction of 25 ppm, 50 ppm, and 100 ppm are dispersed in BCFAD. The investigation results reveal an increase of 6.5% in brake thermal efficiency for BCFAD with 100 ppm nanoparticles when compared to BCFAD. There is a reduction of 29.29% of hydrocarbon and 34% of Carbon monoxide emissions with BCFAD100 in comparison with diesel. However, there is a marginal increase in NOx emission with the increase in nanoparticles. The heat release rate and cylinder pressure of BCFAD100 are comparable to diesel fuel. It was concluded that the utilization of BCFAD with a nanoparticle dispersion of 100 ppm is suitable for direct use as fuel in diesel engines. [ABSTRACT FROM AUTHOR]

Albania is now implementing a range of steps as part of its journey towards European Union integration, based on agreements that have been achieved. Key to these initiatives is the extensive adoption of circular economy concepts through comprehensive waste management systems. This collaboration is based on systematically implementing measures that align with the fundamental principles of the waste management hierarchy. Albania wants to lead in waste-to-energy conversion exploration by focusing on trash minimization, reuse, recycling, and energy generation from residual waste. Although there has been notable advancement, especially in aligning laws with EU requirements, there are practical obstacles, especially in the execution of waste-to-energy projects. The challenges involve the need for effective waste segregation, higher recycling rates, and the use of advanced waste-to-energy technologies. The essay utilizes meticulously selected data on Albania's waste generation from reputable organizations and the legal framework regulating waste management to assess the current situation and predict future possibilities, which may be advantageous for government ministries and agency platforms. [ABSTRACT FROM AUTHOR]

Ghana is currently facing a waste crisis that presents considerable risks to its environment, economy, and public health. This investigation evaluates four prospective waste-to-energy options—namely, incineration, anaerobic digestion, gasification, and landfill gas—with the objective of mapping out a sustainable strategy for efficient waste management. Among these solutions, anaerobic digestion stands out as a superior option, offering renewable energy production, valuable bio-product creation, and a comparatively lower greenhouse gas emission effect. A cost analysis further reveals that utilizing biogas from anaerobic digestion is not only environmentally friendly but also economically more viable than relying on light crude oil. Producing 200 MW of energy using biogas costs 36% less, potentially resulting in monthly savings of USD 5.46 million for Ghana. However, several obstacles impede the development of WtE. Inaccurate waste data and a lack of clear policies on waste-to-energy hinder the harnessing of Ghana's WtE potential. To address this, the study recommends (1) implementing a well-defined national strategy complete with regulations and incentives to attract investments and (2) conducting specialized research to optimize WtE technologies for Ghana's unique waste composition and context. By surmounting these challenges, Ghana stands poised to secure a sustainable future, simultaneously meeting the targets of Sustainable Development Goals 7 and 11. This entails ensuring access to affordable, reliable, sustainable, and modern energy for all (SDG 7) and fostering inclusive, safe, resilient, and sustainable cities and human settlements (SDG 11). [ABSTRACT FROM AUTHOR]

Hydrothermal carbonization (HTC) technology emerges as a sustainable method to convert wet biomass, including food waste and municipal solid waste into high‐energy dense biocoal. This process, conducted at temperatures ranging from 180 to 260°C and pressures of 10–50 bar, effectively transforms the organic material in wet biomass into solid, liquid, and gaseous outputs. The solid product, biocoal, possesses a high carbon concentration and heating values on par with lignite coal, presenting a cleaner alternative to traditional fossil fuels. Despite operational commercial‐scale HTC facilities globally, further adoption across various feedstocks can improve waste management and energy production. The process can achieve energy yields up to 80%, particularly at temperatures favoring the generation of secondary char with higher heating values. HTC not only aids in reducing greenhouse gas emissions through carbon sequestration in solid waste but also promotes environmental sustainability by yielding nutrient‐rich by‐products for agriculture. As a versatile and energy‐efficient solution, HTC technology is a pivotal innovation in waste‐to‐energy conversion, addressing the imperative for sustainable waste management. Other supplementary benefits are presented; they include higher employability, reduction of a nation's reliance on imported energy, and better waste control, therefore considering all pillars of sustainability. Future research should focus on optimizing process efficiency and exploring the broader applicability of HTC to various biomass feedstocks, enhancing its role in the global pursuit of sustainable energy solutions. [ABSTRACT FROM AUTHOR]

Alternative, renewable and carbon-neutral fuels are an urgent requirement. Pyrolysis has received the most attention in the conversion of biomass into fuel. The main disadvantages of chemical and physical properties of pyrolysis crude bio-oil include its high oxygen content and acidity. Catalytic fast pyrolysis can overcome this problem. Rice straw is an abundant biomass residual that can be of environmental negative impact and is not of proper use. Therefore, this research work introduces the use of this residual in the production of fuel sources by one-step catalytic pyrolysis with the reusability of the employed catalyst. A waste extraction catalyst modified with acidic and nickel sites has been prepared and was utilised for the proposed target in this study. The removal of silica, lignin and minerals by treatment of the rice straw with KOH and then HNO3 in a green terminated process improved the catalytic biomass conversion from 83% to 96% at a catalyst dose of 5%, at 250°C. The pre-treatment of the rice straw enables the reusability of the catalyst in direct catalytic pyrolysis where the employed catalyst exhibits good stability in four consecutive runs. The used KOH and HNO3 were neutralised by mixing to produce KNO3 as a valuable fertiliser. [ABSTRACT FROM AUTHOR]

Microbial fuel cells (MFCs) are sustainable energy recovery systems because they use organic waste as biofuel. Using critical raw materials (CRMs), like platinum-group metals, at the cathode side threatens MFC technology's sustainability and raises costs. By developing an efficient electrode design for MFC performance enhancement, CRM-based cathodic catalysts should be replaced with CRM-free materials. This work proposes developing and optimizing iron-based air cathodes for enhancing oxygen reduction in MFCs. By subjecting iron phthalocyanine and carbon black pearls to controlled thermal treatments, we obtained Fe-based electrocatalysts combining high surface area (628 m2 g−1) and catalytic activity for O2 reduction at near-neutral pH. The electrocatalysts were integrated on carbon cloth and carbon paper to obtain gas diffusion electrodes whose architecture was optimized to maximize MFC performance. Excellent cell performance was achieved with the carbon-paper-based cathode modified with the Fe-based electrocatalysts (maximum power density-PDmax = 1028 mWm−2) compared to a traditional electrode design based on carbon cloth (619 mWm−2), indicating the optimized cathodes as promising electrodes for energy recovery in an MFC application. [ABSTRACT FROM AUTHOR]

This paper applies Bayesian inference with normal-normal conjugate to forecast renewable energy generation. The generation forecasts a probability distribution rather than a quantitative value. An assumed normal distribution is initialized for renewable energy generation. This assumed normal distribution's parameters, the mean μ, and the standard deviation σ, are inferred by Bayesian inference afterward. However, applying Bayesian inference barely shall encounter an intractable integral. To circumvent the intractable integral, this paper considers the normal-normal conjugate method. This method fixes the assumed normal distribution's σ and characterizes μ as another normal distribution and then infers the latter normal distribution parameters. A case study of waste-to-energy generation forecast in Taiwan is investigated in this paper. It has been found from the investigation that the Bayesian inferred probability distribution outperforms the assumed one. [ABSTRACT FROM AUTHOR]

Under optimal process conditions, pyrolysis of polyolefins can yield ca. 90 wt % of liquid product, i.e., combination of light oil fraction and heavier wax. In this work, the experimental findings reported in a selected group of publications concerning the non-catalytic pyrolysis of polyolefins were collected, reviewed, and compared with the ones obtained in a continuously operated bench-scale pyrolysis reactor. Optimized process parameters were used for the pyrolysis of waste and virgin counterparts of high-density polyethylene, low-density polyethylene, polypropylene and a defined mixture of those (i.e., 25:25:50 wt %, respectively). To mitigate temperature drops and enhance heat transfer, an increased feed intake is employed to create a hot melt plastic pool. With 1.5 g·min−1 feed intake, 1.1 L·min−1 nitrogen flow rate, and a moderate pyrolysis temperature of 450 °C, the formation of light hydrocarbons was favored, while wax formation was limited for polypropylene-rich mixtures. Pyrolysis of virgin plastics yielded more liquid (maximum 73.3 wt %) than that of waste plastics (maximum 66 wt %). Blending polyethylenes with polypropylene favored the production of liquids and increased the formation of gasoline-range hydrocarbons. Gas products were mainly composed of C3 hydrocarbons, and no hydrogen production was detected due to moderate pyrolysis temperature. [ABSTRACT FROM AUTHOR]

In this study, plastic waste was efficiently converted into valuable energy resources using a unique pyrolysis technique. A carbon-metal oxide hybrid nanocomposite was introduced as a catalyst, and analyses of structural and surface morphology were conducted. Pyrolysis process parameters such as temperature (PTemp), process time (PTime), and catalyst concentration (CC) were optimized through response surface methodology for a higher yield of energy resources. Char underwent proximate and ultimate analyses, oil underwent physicochemical and Fourier transform infrared analyses, and syngas composition was determined. Optimal conditions were found: PTemp 300 °C, PTime 60 min, CC 1 % for char; PTemp 465 °C, PTime 150 min, CC 1 % for oil; PTemp 550 °C, PTime 60 min, CC 4 % for syngas. Compared to the ZSM-5 catalyst, char, oil, and syngas yields increased by 7.9 %, 10.8 %, and 7.2 %, respectively, at optimum conditions. These findings suggest that waste plastic pyrolysis can effectively meet energy demands with enhanced energy outputs.

Ghana is currently facing a waste crisis that presents considerable risks to its environment, economy, and public health. This investigation evaluates four prospective waste-to-energy options—namely, incineration, anaerobic digestion, gasification, and landfill gas—with the objective of mapping out a sustainable strategy for efficient waste management. Among these solutions, anaerobic digestion stands out as a superior option, offering renewable energy production, valuable bio-product creation, and a comparatively lower greenhouse gas emission effect. A cost analysis further reveals that utilizing biogas from anaerobic digestion is not only environmentally friendly but also economically more viable than relying on light crude oil. Producing 200 MW of energy using biogas costs 36% less, potentially resulting in monthly savings of USD 5.46 million for Ghana. However, several obstacles impede the development of WtE. Inaccurate waste data and a lack of clear policies on waste-to-energy hinder the harnessing of Ghana’s WtE potential. To address this, the study recommends (1) implementing a well-defined national strategy complete with regulations and incentives to attract investments and (2) conducting specialized research to optimize WtE technologies for Ghana’s unique waste composition and context. By surmounting these challenges, Ghana stands poised to secure a sustainable future, simultaneously meeting the targets of Sustainable Development Goals 7 and 11. This entails ensuring access to affordable, reliable, sustainable, and modern energy for all (SDG 7) and fostering inclusive, safe, resilient, and sustainable cities and human settlements (SDG 11).

Albania is now implementing a range of steps as part of its journey towards European Union integration, based on agreements that have been achieved. Key to these initiatives is the extensive adoption of circular economy concepts through comprehensive waste management systems. This collaboration is based on systematically implementing measures that align with the fundamental principles of the waste management hierarchy. Albania wants to lead in waste-to-energy conversion exploration by focusing on trash minimization, reuse, recycling, and energy generation from residual waste. Although there has been notable advancement, especially in aligning laws with EU requirements, there are practical obstacles, especially in the execution of waste-to-energy projects. The challenges involve the need for effective waste segregation, higher recycling rates, and the use of advanced waste-to-energy technologies. The essay utilizes meticulously selected data on Albania’s waste generation from reputable organizations and the legal framework regulating waste management to assess the current situation and predict future possibilities, which may be advantageous for government ministries and agency platforms.

• Pressurised pyrolysis is performed on real mattress waste. • Consistent char yields with high energy content. • Yields of C 3 species similar to those of H 2 and C 2 compounds. • High-pressure conditions yield low heating value gas due to N 2 dilution. • Main compounds identified in the liquid fraction are benzonitrile and BTEX. Mattresses are a difficult waste to manage in landfills due to their large volume and low density. Pyrolysis treatment could reduce its volume while producing fuel or products valuable for the chemical industry. Pressurized pyrolysis at 400, 450, and 500 °C is carried out in a lab-scale autoclave at initial pressures 4.2, 8.4, and 16.8 bar. Product gas yield increases slightly along with elevated pressure as well as temperature. However, beyond 8.4 bar the initial pressure makes no discernible differences. CO and CO 2 are the major gas species followed by CH 4. CO contributes the most to the product gas energy content followed by C 3 species, C 2 H 6 , and H 2. Calculated energy content (heating value) is between 2 and 15 MJ·Nm−3. In terms of product gas energy content, low pressure pyrolysis is favorable over high pressure pyrolysis. According to integration areas of chromatographic measurements the liquid phase contains up to 25 % of N-compounds, with benzonitrile being the most abundant, followed by toluene, o-xylene, and ethylbenzene. The solid char maintains constant properties across operating conditions, with carbon and energy contents of approximately 75 wt% and 30 MJ·kg−1, respectively. [ABSTRACT FROM AUTHOR]

The co-digestion of a peach biowaste and parboiled rice effluent mixed with a sludge digester was investigated using a lab-scale biodigester. The biomasses used in the system were characterized by physical-chemical and microbiological analyses. Variations in substrate/inoculum (S/I) ratio of 1:1, 1:2, and 3:2, with different percentages of peach bagasse of 0%, 5%, and 10% in the substrate combination (peach bagasse + effluent), were performed. The study found that co-digestion of peach bagasse and parboiled rice effluent with digester sludge resulted in higher biomethane production, with reactors II and IV showing the best combination of factors both with a proportion of 3:2 (S/I). Reactor IV showed the maximum production of 27.51 mL CH 4 with a substrate composition of 10% peach bagasse and 90% effluent. The physical-chemical properties of the co-digestion substrate were optimal for anaerobic digestion, and the microbial community adapted to enhance biodegradation. The maximum COD removal was found in reactor IV at 88.06%, followed by reactor V at 82.10%. In contrast, the 1:2 (S/I) ratio in reactor I showed the lowest methane production. Furthermore, the co-digestion process resulted in stable and efficient digestion, indicating it is a viable alternative for treating rice parboiling effluent and peach waste. • Alternative for treating rice parboiling effluent and peach waste. • Peach biowaste and parboiled rice effluent characterization. • Maximum production of 27.51 mL CH 4 using anaerobic codigestion process. [ABSTRACT FROM AUTHOR]

The prolific generation of industrial solid waste (ISW) in China, coupled with its complex composition, presents significant challenges due to exceeding environmental capacity. Identifying an appropriate approach to maximize the use of ISW, particularly low-value industrial solid waste (LISW), is crucial for addressing environmental issues. This study explores the potential of converting LISW into refuse-derived fuel (RDF), an energy-rich precursor, as a promising method for disposal and reutilization. The advantages of RDF lie primarily in two key areas: management and technology. Regulatory aspects cover principles governing RDF feedstock preparation, storage and transportation requirements, and pollutant emission regulations. Technical considerations include pretreatment techniques, additive selection, and analyzing RDF as a substitute for fossil fuels. To assess the effectiveness of RDF technology in harnessing the remaining energy from LISW, this paper provides an overview of relevant national laws and regulations concerning incineration plants, guiding the utilization of RDF in such facilities. Additionally, using Shanghai as a case study, we evaluate the ISW situation, domestic waste incineration plants, and cement kiln plants to identify potential scenarios for RDF application in future energy systems. Our findings suggest that LISW holds significant potential as a power plant fuel, particularly when blended with higher calorific value materials to produce RDF particles with exceptional combustion performance, density, and storage characteristics. [ABSTRACT FROM AUTHOR]

Coffee residues (CRs) were gasified using a laboratory-scale fluidized bed gasifier with an air/steam mixture as the carrier gas. The gasification was conducted at an equivalence ratio (ER) of 0.3, and different operation temperatures (700, 800, and 900 °C) and steam-to-biomass (S/B) ratios (0, 0.75, and 1.5) were applied. Increasing temperature without steam boosted H2 and CO concentrations in producer gas, raising lower heating value (LHV) and cold gas efficiency (CGE) through endothermic reactions like Boudouard, tar cracking, and water-gas formation. At 900 °C, gas had LHV of 3.76 MJ/Nm3 and CGE of 22.47%. It was elevating temperature from 700 to 900 °C and S/B ratio to 1.5 raised H2 and CO concentrations from 2.04 to 8.60% and from 9.56 to 11.8%, respectively. This also increased LHV from 2.23 to 3.89 MJ/Nm3 and CGE from 11.28 to 25.08%. The steam gasification reaction was found to increase the H2 concentration and was thus considered effective in converting CRs to syngas and increasing energy production. Overall, the study successfully demonstrated the feasibility of steam gasification as a means of converting coffee residues to syngas and increasing energy production. The results also highlighted the importance of operating temperature and S/B ratio in improving the gasification process. [ABSTRACT FROM AUTHOR]