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This study investigates the impact of incorporating lime mud (LM) as a filler material to develop sustainable, cementless ultra-high performance concrete (UHPC) by replacing silica powder (SP) and silica sand (SS) at varying percentages. Flowability analysis reveals that LM, with its distinctive particle size, influences flow characteristics differently at different replacement levels. Compressive strength was improved by 5.4% with 30% SP replacement, showcasing the role of LM in nucleation, as well as its particle size advantage. The heat of hydration analysis indicates that LM likely influences the early curing stages, enhancing reactivity and nucleation. TGA analysis also confirms that LM plays a role in hydration reaction, influencing weight loss and hydration peaks. The mercury intrusion porosimeter results show the impact of LM on pore distribution, with 30% for SP and 50% for SS replacements, favoring denser matrices. Life cycle assessment (LCA) demonstrates reduced CO 2 emissions and favorable environmental performance, highlighting the sustainability potential of LM replacements. Overall, the incorporation of LM in UHPC shows promise in terms of enhancing its mechanical properties and environmental sustainability. [Display omitted] • Lime mud (LM) in UHPC boosts material strength, leading to denser, more effective concrete. • LM enhances hydration, flowability, and refines pore structure. • High LM ratios in UHPC increase sustainability and reduce CO 2 emissions. • LM's use in UHPC significantly advances its mechanical properties and eco-friendliness. [ABSTRACT FROM AUTHOR]

With the development of energy technology, hydrogen is gradually becoming widely used. China is also rapidly developing its own hydrogen energy industry in an effort to accomplish the "dual carbon target'. Hydrogen from methane is one of the mainstream sources, of which hydrogen from methane cracking is the decomposition of methane into hydrogen and solid carbon, with the solid carbon also having a high economic value. In particular, this technology does not emit carbon dioxide, which is very friendly to the environment, but it cannot avoid larger energy consumption. In contrast, hydrogen production from methane cracking driven by solar energy not only combines the characteristics of no CO 2 emission, but also greatly reduces the consumption of primary energy, which is the future development trend of hydrogen production from methane. This paper provides a brief overview of the various technological pathways for methane to hydrogen production in the context of China's actual development, focusing on the current status of the development and application of solar methane cracking to hydrogen production technologies at home and abroad. Among them, this paper mainly discusses the characteristics of solar reactors of different sizes and structures, and summarizes the results of related optimization studies. Meanwhile, the application of catalysts in solar reactors and the problem of carbon deposition are analyzed, and the practical application of solar methane cracking hydrogen production system is outlined. Finally, the future development of solar methane cracking hydrogen production technology is prospected from the national situation of China. [Display omitted] • Solar methane cracking for hydrogen can reduce emissions and energy consumption. • The current state of research on solar reactors is summarized. • Solar methane cracking requires higher performing catalysts. • Providing insights into the future development of solar methane cracking in China. [ABSTRACT FROM AUTHOR]

The environmental issues within the transport industry need to be given priority attention. Optimizing the transport structure and promoting low-carbon transport are essential measures for achieving carbon emission reduction. However, the rail-water multimodal transport scale is currently limited. The government has to intervene in the market through incentive policies, so how to expand the revenue of carriers and enhance the volume has become a major dilemma. Our paper constructs a transport system that includes road, water, and railway, and examines the impact of incentive policies on separate stakeholders. It is discovered that incentive policies can increase the revenue of carriers and simultaneously attract more shippers to elect rail-water multimodal transport. Subsidy policy can hasten the structural transformation of inland transport, making railway transport volume rise. Unfortunately, although the dry port policy may enhance the revenue of railway carriers, it leads to an apparent decline in the revenue of road-water multimodal transport participants. However, the subsidy policy can create a win-win scenario for multiple carriers while achieving carbon emission reduction, but to the detriment of social welfare. Additionally, the paper compares the interactions between diverse incentive policies and pivotal factors such as transport time. The conclusions of our research serve strategic recommendations for maximizing carriers revenues and provide support for government decision-making. • The impact of incentive policies on the rail-water multimodal transport is inspected. • Subsidy policy can make carriers better off, but may have adverse effects on social welfare. • Subsidy policy expands carrier volume and stimulates transport structure transformation. • Although dry port is conducive to social welfare, it hurts the revenue of carriers. • The dry port is beneficial for achieving long-distance carbon emissions reduction. [ABSTRACT FROM AUTHOR]

Urbanization and the release of carbon emission are two significant features of contemporary economic and social progress in China. However, there are few studies that consider how urbanization policy goals affect carbon emission. This paper aims to study the nonlinear effects of urbanization policy goals on carbon emission in 13 cities of the Beijing-Tianjin-Hebei region. In this paper, a multi-dimensional spatial disturbance grey model is proposed. Based on matrix perturbation theory, this paper explores the spatial perturbation bounds of the novel model and verifies that the spatial property of the model is consistent with the viewpoint of the First Law of Geography. Then, the novel model is used to predict the urban carbon emission under different urbanization policy goal scenarios. The results showed that the novel model has spatial regional correlation in spatial region prediction. With the development of urbanization level, carbon emissions show a downward trend in more than 50% of cities from 2022 to 2025. In addition, the improvement of urbanization policy goals will promote the carbon peak time of most cities. The carbon emission intensity will exhibit an inverted U-shaped trend distribution in space. The research results are conducive to providing scientific guidance for the formulation of new-type urbanization policies and helping to achieve the dual carbon goals. • A multi-dimensional spatial disturbance grey model is proposed. • The novel grey model is consistent with the viewpoint of the First Law of Geography. • The spatial distribution of carbon intensity showed an inverted U-shaped pattern. [ABSTRACT FROM AUTHOR]

COVID-19 has represented a watershed in people's lifestyle. One important consequence has been the change in how people buy groceries online/offline that represent the most frequent shopping-related trip any household performs. Since this has substantially different transport and environmental implications, it is crucial to investigate what are the COVID-19-induced variations. This paper estimates both travel and environmental impacts grocery channel choice implies by comparing, in a diachronic fashion, the pre and during COVID-19 situation in Norway, considering alternative scenarios describing different service configurations for each channel considered. Stated preferences are used to estimate market shares for grocery purchase distinguishing between different channels: in-store, home delivery and click&pick. The robust comparative analysis between the two time periods is guaranteed by the use of the same methodological approach in the same geographical context. Results show that total emissions are lower during the pandemic and adopting a free delivery strategy not only increases home delivery market shares but also produces the lowest level of CO2 emissions regardless of COVID-19. The results obtained are particularly relevant in the "new normal" the world is experiencing both from a public policymaking perspective, when promoting transport-related interventions to curb emissions, and from a private standpoint, when customising market strategies to increase sales and profits. • COVID-19 has represented a watershed in people's lifestyle. • Investigating changes in how people buy groceries online/offline is important. • Stated preferences are used to estimate grocery market shares for different channels. • The paper estimates travel and environmental impacts pre and during COVID-19 via scenario analysis. • Results are particularly relevant for both the public and private sector in the "new normal" conditions. [ABSTRACT FROM AUTHOR]

Hydrogen is considered as a promising fuel in the 21st century due to zero tailpipe CO 2 emissions from hydrogen-powered vehicles. The use of hydrogen as fuel in vehicles can play an important role in decarbonising the transport sector and achieving net-zero emissions targets. However, there exist several issues related to hydrogen production, efficient hydrogen storage system and transport and refuelling infrastructure, where the current research is focussing on. This study critically reviews and analyses the recent technological advancements of hydrogen production, storage and distribution technologies along with their cost and associated greenhouse gas emissions. This paper also comprehensively discusses the hydrogen refuelling methods, identifies issues associated with fast refuelling and explores the control strategies. Additionally, it explains various standard protocols in relation to safe and efficient refuelling, analyses economic aspects and presents the recent technological advancements related to refuelling infrastructure. This study suggests that the production cost of hydrogen significantly varies from one technology to others. The current hydrogen production cost from fossil sources using the most established technologies were estimated at about $0.8–$3.5/kg H 2 , depending on the country of production. The underground storage technology exhibited the lowest storage cost, followed by compressed hydrogen and liquid hydrogen storage. The levelised cost of the refuelling station was reported to be about $1.5–$8/kg H 2 , depending on the station's capacity and country. Using portable refuelling stations were identified as a promising option in many countries for small fleet size low-to-medium duty vehicles. Following the current research progresses, this paper in the end identifies knowledge gaps and thereby presents future research directions. • Technological advancements of hydrogen production, storage and transport are reviewed. • Emissions and economic aspects of production, storage, transport and fuelling are analysed. • Refuelling protocols, temperature rise issue and its control strategies are discussed. • Recent progress of mobile hydrogen refueller is explored. • Challenges of hydrogen production to fuelling and future research directions are presented. [ABSTRACT FROM AUTHOR]

Recently, ammonia is getting more attractive as a potential alternative fuel for future power generation and transportation purposes due to its ability to reduce consumption of fossil fuels, soot, CO 2 emissions, and hydrocarbon pollutants. In the recent past, several studies aimed to the development of ammonia combustion systems have been conducted. However, ammonia combustion systems face several challenges, such as poor ignition timings, lower burning velocity, low energy density, shorter flammability limits than hydrocarbons. These issues are compounded by the significant increase in NOx emissions, which makes practical application of ammonia challenging. Various conventional methods, such as blending ammonia with other hydrocarbons and hydrogen, have been employed to improve combustion performance and reduce NO x emission. Meanwhile, it increased the engine complexities and at the same time, it raised CO 2 and NO x emissions. Recently, plasma-assisted combustion (PAC) has emerged as a promising technology to boost the ammonia combustion process by improving ignition delay timings, increasing flame speed, extending flammability limits, and reducing NO x emissions. In recent years, plasma-assisted combustion (PAC) has emerged as a promising technology to enhance the ammonia combustion process by improving ignition delay timings, increasing flame speed, extending flammability limits, and reducing NOx emissions. Nevertheless, only a few studies on plasma-assisted ammonia combustion (PAAC) are available in the literature. This review paper aims to summarize the latest advancements in the field of PAAC during the last years, including progress in the development of numerical models and experimental studies. The paper highlights the detailed procedure of PAAC numerical modeling and the limitations of numerical models. Finally, the latest numerical and experimental developments of PAAC have been discussed. • Ammonia is getting more attraction as an alternative fuel for future power and transportation sectors. • A comprehensive outlook of non-thermal plasma for ammonia combustion is provided. • The in-depth mechanisms of plasma assisted combustion are highlighted. • The latest numerical and experimental studies of Plasma assisted combustion were analyzed. [ABSTRACT FROM AUTHOR]

The ever-increasing challenges related to water security and climate mitigation underscore the pressing need for forward-thinking systems planning tools to drive urban sustainability transitions. In this study, we propose a novel city-level multi-objective planning framework that explores the nexus between carbon trading and water management, with the aim of facilitating water-efficient urban industrial restructuring. The framework integrates cap-and-trade mechanisms into a two-layered optimization model, creating an integrated approach to optimizing carbon emissions and generating economic opportunities for improving water efficiency. To illustrate the potential application of this framework, we conducted a case study focusing on Dongguan City, a water-stressed industrial metropolis in southern China. The results illustrate potential synergies between water planning strategies and carbon trading schemes, which could be harnessed to enable targeted reductions in water usage and carbon emissions. Furthermore, our findings identify the textile, apparel, and paper products manufacturing industries as primary candidates for strategic production scale reduction, emphasizing the importance of sustained support for the development of the computer and electronic manufacturing sector as a catalyst for urban sustainability transitions. By pioneering this new nexus-based perspective, our study offers valuable insights into long-term strategic planning for a low-carbon and resource-efficient urban economy. • Synergizing carbon trading and water management within a novel integrated planning framework. • Implementing resource-efficiency-driven optimization for water- and carbon-intensive manufacturing sectors. • Gaining insights into the specific roles of key manufacturing sectors in water management and carbon trading. • Introducing carbon trading systems may help in promoting water-efficient industrial restructuring. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • TGA analysis was performed for MSW components (food waste, paper, and plastics). • Solid residues of paper were 2 and 10 times higher than plastic and food. • Air/CO 2 reduced the burnout temperature by 300 ℃ for food waste than CO 2. • Combustion index (S) of MSW under Air/CO 2 was 4 times more than CO 2. • MSW reduced H f by 2.5 times than food waste, promising better combustion. This study examines the gasification kinetics of Brazilian municipal solid waste (MSW) and its components under air, CO 2, and air/CO 2 (70/30 vol%) atmospheres. The ignition indices of paper and plastic are 6 and 3 times that of food waste, which are 38.6 × 10−3 %/min3 and 19.6 × 10−3 %/min3, respectively, implying a faster separation of volatile compounds from the paper and plastic. The minimum E α values of 132 kJ/mol and 140 kJ/mol have been obtained for paper waste under air and air/CO 2 , respectively. On CO 2 condition, MSW has an average E a value of 96 kJ/mol. Under an air/CO 2 atmosphere, a high synergistic ΔW of −4.7 wt% has been identified between individual components. The presence of air and CO 2 improves the oxidation and char gasification process, thus resulting in better combustion. Hence, the gasification of MSW under an air/CO 2 atmosphere would improve the waste-to-energy plant's performance and minimize the CO 2 emission. [ABSTRACT FROM AUTHOR]

The current study examines a novel multigeneration plant that uses geothermal energy to produce clean and sustainable products. The process includes a re-compression supercritical Brayton power plant (re-sBC), an ejector cooling unit (EJCS), a humidifier dehumidifier desalination (HDH) unit, a Proton-Exchange Membrane (PEM) process, and a hot water preparation unit. The designed plant is able to generate hot water, cooling, power, hydrogen, and freshwater using the geothermal source. In the current paper, the thermodynamic analysis, CO 2 emission assessment, and exergoenvironmental index evaluation are executed to determine the system efficiency and the association between the system and the environment. A thorough parametric examination is fulfilled, to show how the system indicators impact efficiency and generated products. According to analysis data, the proposed multigeneration plant is able to generate 1278 kW of heating load, 229.6 kW of refrigeration capacity, and 109.5 kW of net power rate. Additionally, the capacity of the freshwater is 0.1188 kgs − 1 and the hydrogen is 0.001317 kgs − 1 . This developed system emits a total of 117 tonnes of CO 2 emissions per year for these useful outputs. In conclusion, the energetic and exergetic performance of the suggested MG plant are 14.09 % and 23.35 %, respectively. • A sustainable geothermal energy-based MG is proposed. • The thermodynamic, emission, and environmental analysis is conducted. • Design and evaluation of the Green hydrogen production and storage. • Re-compressed sBC integrated into geothermal driven MG plant. • Total energy and exergy efficiency is computed as 14.09 % and 23.35 %, respectively. [ABSTRACT FROM AUTHOR]

Ports are essential and strategic nodes of international trade and economic activities. The integration of port resources helps enhance the optimal division of port functions to further promote economic development. This paper explores the evolutionary trends of port integration policy from 2011 to 2021 in China through a text-mining approach. We first used the Latent Dirichlet Allocation (LDA) topic analysis method to analyze the port integration policies and summarize the evolutionary trends of port policies. In addition, an association analysis was conducted to explore port integration policies' impacts by examining their relationships among the environmental protection, digitalization level, and port development scale. Our findings suggested that China's port integration policy has evolved from specific and simple to abstract and complicated at the managerial level. Port development has enriched from infrastructure construction to the ideology of economic development. Our findings show that China's port integration is gradually improving the port operation. The findings of the study contribute to the extant literature by analyzing the port integration policy evolution in China and can be referred to by other countries. • Text mining method was used to explore the port integration policy evolution. • Port integration policy evolved from specific and simple to abstract and complicated. • Port development enriched from basic infrastructure to the governance model. • The evolution of port integration policy was related to reducing carbon emissions in the port sector. • The evolution of port integration policy made the ports intelligent in association with digital technology such as big data and AI. [ABSTRACT FROM AUTHOR]

Hydrogen is crucial in the forthcoming low-carbon energy systems offering the potential to reduce CO 2 emissions and its versatility to be utilized across diverse energy sectors. Precise assessment of hydrogen thermo-physical characteristics is vital for the effective design and execution of numerous processes encompassing hydrogen production, transportation, storage, and utilization. In this paper, various distinct machine learning (ML) approaches, namely extreme gradient boosting (XGBoost), Random Forest (RF), Adaptive boosting (AdaBoost), and Light gradient boosting machine (LightGBM) were implemented to estimate thermo-physical properties, namely thermal conductivity, density, viscosity, and diffusivity in water based on pressure and temperature variables. For this purpose, comprehensive experimental data points covering a broad range of pressures and temperatures were acquired from the literature. The results demonstrated a strong agreement between the predictions generated by all proposed techniques and the experimental data. Furthermore, XGBoost yielded a root mean square error (RMSE) of 0.0085, 2.1548, 0.3343, and 1.5308 for the estimation of thermal conductivity, density, viscosity, and diffusivity, respectively, demonstrating superior accuracy in predicting all outcomes. In the sensitivity evaluation, it was observed that temperature, with absolute relevancy factor 0.88, 0.54, 0.246, and 0.92 had the most significant influence on the hydrogen thermo-physical properties in the order mentioned above. Furthermore, the trend analysis of the model indicated that all thermo-physical properties of hydrogen experience positive effects from temperature and pressure, except for density, which decreases as temperature increases. The leverage technique confirmed the statistical validity of both the experimental dataset used for modeling and the model's development. This study's results provide the efficient design and secure operation of hydrogen storage, refueling stations, transportation infrastructure, and production facilities. [Display omitted] • Hydrogen holds great importance in the forthcoming low-carbon energy. • XGBoost, RF, AdaBoost, and LightGBM are utilized for modeling the thermo-physical properties of hydrogen. • XGBoost demonstrates its superior accuracy in predicting thermal conductivity, density, viscosity, and diffusivity. • Temperature has the most significant influence on the hydrogen thermo-physical properties. [ABSTRACT FROM AUTHOR]

Excessive NO x and CO 2 emissions pose a significant challenge in the clean combustion of natural gas, which is expected to be solved through the combination of exhaust gas recirculation and hydrogen enrichment. In this study, the pollutant emission and temperature distribution of a laminar diffusion flame during the combustion of CH 4 mixed with CO 2 /N 2 /H 2 are experimentally investigated. The NO emission reduction effect of CO 2 dilution on hydrogen-enriched methane is evaluated as well. The experimental results show that CO 2 dilution has a deeper NO emission reduction and flame temperature attenuation than N 2 dilution. At a given blending ratio of 50%, CO 2 dilution effectively reduces NO emissions by approximately 50%, whereas N 2 dilution decreases NO emissions by about 10%. Compared with N 2 dilution, the peak flame temperatures of CO 2 dilution cases are reduced by 15.3 K, 45.1 K, 31.7 K, 32.6 K, and 44.3 K, respectively, when the blending ratios increase from 10% to 50% with an interval of 10%. The difference caused by the CO 2 /N 2 dilutions between the inhibition effect from the inherent attributes and the enhanced mixing effect on the flame temperature, results in a significant peak temperature gap of 45.1 K at a 20% blending ratio. H 2 enrichment enhances the flame temperature and promotes the combustion reaction process, resulting in a more compact flame structure. NO emission factors for H 2 blending ratio of 0% and 50% are 1953 mg·(kg Fuel)−1 to 2544 mg (kg Fuel)−1, respectively, which is due to the excessive NO generation because of the temperature rise in the combustion zone. CO 2 dilution demonstrates an excellent NO emission reduction effect on hydrogen-enriched methane gas. This paper may provide some references for the development and application of exhaust gas recirculation and hydrogen enrichment. • The combustion characteristics of CH 4 mixed with CO 2 /N 2 /H 2 are investigated. • CO 2 is better than N 2 in NO emissions reduction and flame temperature attenuation. • H 2 enrichment increases the NO emissions and decreases the CO emissions. • H 2 enrichment increases the flame temperature and promotes combustion reaction. • CO 2 shows an excellent NO emissions reduction for hydrogen-enriched methane. [ABSTRACT FROM AUTHOR]

[Display omitted] • Glass fiber wind turbine blades (WTBs) can provide raw material to produce cement. • Glass fiber WTBs can serve as fuel and replace coal to produce cement. • High boron in some glass fiber WTBs might limit replacement rates. • Combustion of fossil-fuel polymer in WTBs can slightly reduce plant CO 2 emissions. • Glass fiber wind turbine blades are compatible with the cement production process. The objective of this paper is to evaluate the feasibility of co-processing wind turbine blade (WTB) material in cement manufacturing to provide an end-of-life means to divert the solid waste of decommissioned WTBs from landfills. Many WTBs consist primarily of glass fiber reinforced thermoset polymers that are difficult to recover or recycle. Portland cement is produced world-wide in large quantities, requiring immense quantities of raw materials (mostly calcium oxide and silicon oxide) and kiln temperatures approaching 1,450 °C. This work contributes analyses of WTB material composition, and predicts the energy provided through the combustible components of the WTBs and raw material contributions provided by incorporating the incombustible components of the WTBs to produce cement. Approximately 40 to 50 % of the WTB material will contribute as fuel to cement production, and approximately 50 to 60 % of the WTB material is expected to be incombustible. One tonne of WTB material can displace approximately 0.4 to 0.5 tonne of coal, while also contributing approximately 0.1 tonne of calcium oxide and 0.3 tonne of silicon oxide as raw material to the cement production process. The glass fiber WTB tested had an average boron content of 4.5 % in the ash. The effects of this high boron content on the cement and its production process should be evaluated. Co-processing WTBs in cement plants will slightly reduce combustion-related CO 2 emissions due to avoided calcination. It seems feasible to co-process glass-fiber reinforced WTBs in cement production as WTBs provide suitable raw materials and compatible fuel for this process. [ABSTRACT FROM AUTHOR]

Pollution reduction and low-carbon development are two specific but intertwined goals of addressing climate change and sustainable development of the United Nations in 2030, and the effective use of digital financial inclusion is imperative for driving technical innovation, upgrading industrial structure, and addressing climate change. Therefore, this paper investigates the impact of digital financial inclusion on the coupling coordination between pollution reduction and low-carbon development using a panel dataset of 30 China's provinces from 2011 to 2020. The results show that the coupling coordination between pollution reduction and low-carbon development in China improves significantly during the sample period. The synergistic effect of different economic zones and provinces varies greatly in space and time. In addition, digital financial inclusion has a promoting effect on the coupling coordination of pollution and carbon emission reduction. A mechanism analysis also reveals that technological innovation, industrial structure and energy consumption are the core transmission channels through which digital financial inclusion influences the synergistic effect of pollution and carbon emission reduction. This suggests that the need of coordinated governance by policymakers is warranted, and digital financial inclusion is an important way to this coordinated governance. [ABSTRACT FROM AUTHOR]

The Chinese government aims to balance employment stabilization and emissions reduction when it initiates an emissions trading scheme (ETS) to control carbon emissions. However, the policymakers should not neglect the role of imperfectly competitive market structure and market power from incumbent firms. In view of this, classical framework of Berman and Bui's (2001) is extended in this paper to clarify the theoretical mechanism of employment effect of the ETS considering firm-level market power. In addition, based on the firm-level panel data from 2008 to 2019 of China, the employment effect of each pilot ETS is measured with the method of difference-in-difference-in-differences. Then a moderating effect model is established to verify the role of firm-level market power on the heterogeneous employment effect among the pilot ETSs. Moreover, the employment effect is further decomposed to evaluate the influential mechanism from the perspective of firms' strategic behavior. It is found that there is negative employment effect of China's ETS policy, due to the significant moderating role of firm-level market power. This decrease in labor demand is mainly dominated by a negative output effect rather than a positive substitution effect because strategic allowance sellers with stronger market power tend to hire fewer employees to reduce carbon emissions by controlling production scale. However, the heterogeneity of policy effects resulted by market structure is also identified in different pilot regions. Employment dividend has been found in Beijing and Tianjin where strategic allowance buyers manipulate the carbon market and hire more employees to consolidate their market power. Therefore, policymakers should improve the design of the ETS to overcome the adverse employment effect duo to the region-specific market structure. [ABSTRACT FROM AUTHOR]

Fossil-based natural resources are carbon-intensive, and over-reliance on them often leads to persistent high carbon emissions at national or regional levels, resulting in the carbon curse. Based on the panel data of 114 resource-based cities in China from 2007 to 2020, this paper examines the carbon curse and solutions for these cities from the perspectives of total and intensity of carbon emissions. The results show that: Firstly, due to the different stages of urban development, resource endowment, degree of resource dependence, and policy background, there is a heterogeneity of carbon curse in China's resource-based cities. Secondly, the carbon emission trading policy can effectively mitigate the carbon curse in China's resource-based cities, and the robustness tests demonstrate the validity of this finding. Thirdly, under the carbon emission trading policy, industrial structure upgrading and digital transformation can play a secondary moderating role in resolving the carbon curse in resource-based cities, further strengthening the inhibitory effect of the carbon emission trading scheme on the carbon curse. In contrast, green technology innovation exhibits no enhancement in the impact of the policy. These findings contribute to the existing research on the carbon curse, offering valuable insights and policy implications for effectively addressing this challenge. [ABSTRACT FROM AUTHOR]

How to improve carbon emission efficiency (CEE) to achieve sustainable economic development has triggered contemplation among society and policy-makers. Previous studies have confirmed that e-commerce development can reduce local carbon emissions, but the impact of e-commerce development on CEE is unclear. This paper investigates the impact of e-commerce development on CEE and its spatial spillover effect using Chinese city-level panel data, taking the National E-commerce Demonstration City (NEDC) policy as a quasi-natural experiment. Results show that the NEDC policy significantly improves local CEE by promoting industrial structure upgrading, green technology innovation, and improving energy efficiency. The influence is more pronounced in regions with inadequate information infrastructure, unfavorable business environment, and limited marketization. However, the NEDC policy has a negative spatial spillover effect, reducing surrounding cities' CEE. The findings unveil the complicated impact of e-commerce development on CEE and offer policy implications for improving inter-regional carbon reduction synergy and low-carbon economic transformation. [ABSTRACT FROM AUTHOR]

• Carbon emissions trading, industrial structure upgrading and green development are integrated into a unified analytical framework. • Taking the carbon trading mechanism as the moderating variable can effectively combine the method of comparative static analysis. • Whether in the long term or the short term, the carbon pilot policy and the industrial structure upgrading policy implemented at the same time will have excess benefits. • When factor flow between cities is considered, excess benefits still exist significantly. Clarifying the influence mechanisms of carbon emissions trading scheme (ETS), industrial structure upgrading (ISU), and green development is of great theoretical and practical significance. Existing studies have only focused on the role of ETS or ISU on green development and have not included them in an analytical framework. The DID model and the moderating effect model are therefore combined in this work to to explore how the ETS will affect the link between ISU and green development throughout the period of 2008 to 2019 using panel data from 271 Chinese cities. Through a series of robustness and endogeneity tests, we find that: (1) ETS can significantly moderate the U-shaped relationship between ISU and green development, and this impact is significant in both the long and short term; (2) When ETS and ISU are implemented at the same time, the effect of the combined actions is greater than the sum of the effects of the two policies implemented separately, which means that the combined actions has excess dividends; (3) ETS and ISU have significant direct effects and spatial spillover effects on green development, and the excess dividends of combined actions also exist significantly at the spatial level. The research results of this paper provide an important theoretical and empirical basis for establishing the combined actions of ETS and ISU. [Display omitted] [ABSTRACT FROM AUTHOR]

This paper proposes a multi-objective framework for sustainable scheduling of hybrid hydrogen-power systems. In the proposed model, the microgrid system incorporated renewable energy systems, battery energy storage systems, non-renewable resources, power-to-hydrogen, hydrogen-to-power, demand response programs, and hydrogen storage systems to present a highly flexible structure in the energy systems. The purpose of the proposed model is to provide a complete operation mechanism for the daily scheduling of microgrids considering environmental, economic, and sustainable problems. To this end, a stochastic three-objective optimization model is proposed to consider the intermittent behavior of renewable generation, loads, and market prices and simultaneously tries to minimize the carbon emission, total cost, and peak loads. The peak load reduction is important because it increases the reliability, renewable energy integration, power quality, and reduced cost of reserve capacity. Therefore, a min-max approach is presented to reduce the peak load in the proposed model. Also, the hydrogen-to-power and power-to-hydrogen resources are integrated as flexible resources to increase the efficiency of microgrids during operation scheduling. The proposed model is evaluated on a standard case study and the numerical results show the multi-objective model reduces the carbon emission by 28.05 kg and increases the load factor by 6.26%, respectively. • Description of a multi-objective problem that integrates electricity and hydrogen. • Proposing an enviro-economic model to reduce carbon emission and operating cost. • The proposed model significantly uniforms the load profile by min-max approach. • Hydrogen storage tank and DR programs are considered to increase the flexibility. [ABSTRACT FROM AUTHOR]

Hydrogen energy is recognized as a crucial solution for addressing energy crises and advancing energy conservation and emissions reduction. It will play a significant role in the future integrated energy systems (IESs). However, the influence of seasonal variations in scheduling optimization of hydrogen-integrated energy system has rarely been investigated. A low-carbon scheduling model for IES, adopting multiple demand responses and a ladder-type carbon trading mechanism, has been established. Additionally, a multi-time scale dispatch optimization strategy considering seasonal hydrogen utilization is thus proposed in this paper. Specifically, day-ahead scheduling optimizes the system taking into account the seasonal variations of renewable energy and load. In the intraday stage, rolling optimization is adopted to address the forecasting errors introduced by wind and photovoltaic fluctuations. In the real-time stage, chance-constrained methods are employed to ensure short-term supply-demand balance. The efficacy of the proposed strategy is verified using real-world measurements, and the results show the multi-time scale scheduling strategy and multiple demand responses effectively enhanced the system's self-regulation capability, leading to a 12% increase in renewable energy absorption. In addition, seasonal hydrogen utilization is essential for system design, as it enhances the absorption of renewable energy, reducing the purchase cost by 4% and the total cost by 2.6%. • Integrated energy system considering seasonal hydrogen utilization. • Multi-time scale optimization with multiple demand response. • Ladder-type carbon trading mechanism reduces system carbon emissions. • Refined hydrogen utilization increased renewable energy absorption by 12%. [ABSTRACT FROM AUTHOR]

This paper presents the preliminary design and thermodynamic analysis of hydropower and solar integrated e-fuel production system for a tea factory. In this regard, an integrated hydro-solar e-fuel production system has been developed, which is mainly able to produce e-methanol and green hydrogen. The system contains five main subsystems: i) Proton exchange membrane electrolyzer system, ii) CO 2 capture and storage system, iii) Methanol production system, iv) Photovoltaic system, and v) Penstock hydroelectric power plant. In terms of the general system operating principle, it is important to emphasize that the energy need of the system is supplied by solar power plant during the sunshine duration (the case 1) and provided by hydropower plant in the period when solar energy is not sufficient (the case 2). Considering the required assumptions, in the first step, preliminary design was performed, and in the second step, the energy and exergy analyzes were achieved, and in the final step, the effects of parameters such as CO 2 capture efficiency, methanol reactor conversion ratio, and environmental temperature on the system performance were parametrically investigated. Accordingly, in the case 1, the maximum energy and exergy efficiencies of the integrated e-fuel production system were respectively obtained to be 7.132% and 6.569% while, in the case 2, those were respectively calculated to be 39.44% and 42.36%. Moreover, approximately 235.9 tons of CO 2 emission in operation period of the tea factory considered in this work can be reduced by the integrated hydro-solar e-fuel production system that has a production capacity of 399.8 kg/h for methanol and 37.73 kg/h for hydrogen. It is expected that the integrated system concept may contribute to the researchers, system designers, policy makers, investors, and different enterprises for practical applications. • Hydropower and solar integrated e-fuel production system for a tea factory is proposed. • The preliminary design and thermodynamic analysis have been performed. • Thanks to the developed systems, 235.9 tons of CO 2 emissions can be reduced. • The maximum exergy efficiency of case-1 and case-2 are obtained to be 6.569% and 42.36%, respectively. [ABSTRACT FROM AUTHOR]

This research stems from the urgent need to address the complex challenges faced in multimodal transportation within the cargo sector, particularly concerning the reduction of transportation costs and CO 2 emissions. Existing transportation systems often struggle to efficiently balance economic and environmental concerns, necessitating innovative solutions. In this paper, we have introduced a novel mathematical model that integrates Singular Value Decomposition (SVD), Genetic Algorithms (GA), and the Adaptive Neural Fuzzy Inference System (ANFIS). The synergy of GA and the ANFIS forms a dynamic learning system that continually refines solutions by adapting to historical decisions and aligning with supply-demand dynamics. This integrated approach aims to optimize cost allocation and resource utilization while simultaneously minimizing CO 2 emissions. Deploying the ANFIS+GA+SVD model in multimodal scenarios yields impressive results, with a minimal average percentage error (MAPE) of 0.28% for transportation costs and a remarkable coefficient of determination R2 of 0.992 for the Truck + Ship scenario. Similarly, a MAPE of 0.11% for CO 2 emissions, supported by an impressive R2 of 0.989, underscores the model's accuracy. Observations of people's transportation choices in response to emission price changes reveal a significant decrease in truck usage, plummeting from 84% to below 50%. Alternative transportation methods, especially in the 3S-3 M-3 C scenario, show a substantial surge, with railways leading at a remarkable 30% increase in utilization. The combined quantity and cost comparison, utilizing the ANFIS+GA+SVD model, emphasizes the suitability of the Truck + Ship scenario for Iraq's transportation network, reinforcing the case for sustainable and efficient multimodal transportation systems. [ABSTRACT FROM AUTHOR]

Green hydrogen has become more attractive as a fuel for engines to reduce greenhouse gas emissions. By mixing it with natural gas (NG), the modification work on the engine can be minimized but the carbon dioxide emissions from combustion can still be decreased. In this paper, an experimental study was accomplished to investigate the performance of a spark-ignition engine fueled with hydrogen-natural gas blends by either keeping a constant ignition timing or changing it. Up to 25 mol-% hydrogen was mixed into natural gases with different compositions and the methane number and Wobbe index were calculated and compared to the requirements set by Euromot. The results show that up to 15 mol-% hydrogen can be blended into NG to meet the limits of Euromot. However, when 25 mol-% hydrogen was mixed into NG the methane number varied between 56 and 64 depending on the gas composition. This would most likely cause knock for a mixture consisting of higher hydrocarbons but during the executed tests knock was never a problem. Furthermore, it was detected that the methane number alone cannot tell the knock tendency of a gas in a certain engine and an additional condition is needed such as the hydrogen level. An adjusted ignition timing was also preferable compared to a constant one to keep the engine component temperature at a moderate level. • A SI-engine was fueled with different hydrogen-natural gas (H 2 -NG) mixtures. • Wobbe index and methane number (MN) were calculated for all test points. • Efficiency was improved and emissions were decreased with higher hydrogen content. • No tendency of knock when 25 mol-% hydrogen was mixed into natural gas with a low MN. • Additional condition is needed for MN eg. H 2 -level to be sure if knock can happen. [ABSTRACT FROM AUTHOR]

In continuation of the previous part, this paper comprehensively focuses on energy, exergy, exergo-economic, and environmental (4E) analyses of two prioritized clean hydrogen (H 2) supply chains pathways. The first scenario relies on domestic demand , involves blue H 2 production and storage using steam methane reforming coupled with carbon capture and storage through H 2 conversion to hydrogen carriers in liquid form (ammonia and methanol) aligned with the existing infrastructure. The second scenario involves green H 2 production from photovoltaic panels as the power source follows by storing H 2 in liquid form which is more suitable to export. The findings indicate that the blue H 2 system outperforms the green H 2 system in terms of energy and exergy, boasting 41.38% and 22.15% compared to 12.16% and 12.75%, respectively. However, when examining economic parameters, the blue H 2 system shows a total cost rate of 1976 US$/h, a net profit of $747.2 million (mn) at the end of its lifetime, and a payback period of approximately nine years. Conversely, the green H 2 system demonstrates economic indicators of a 125.2 $/h as a total cost rate, $1.26 billion (bn) net profit, and an 8.17 year payback period. Moreover, the production cost rates for blue and green H 2 are 1.32 $/kg and 2.55 $/kg, respectively; while the CO 2 emissions rate in the blue H 2 system is 10.71 kg/s. The green H 2 system prevents 19.84 kg/s of CO 2 emissions resulted a significant environmental cost reduction of 2.28 $/kg H 2. This analysis facilitates a thorough comparison of these two clean H 2 production and storage systems, offering insights for policymakers across performance, economic, and environmental dimensions. • A comprehensive 4E analysis was applied for the selected H 2 value chain scenarios. • Blue H 2 scenario is superior economically while environmentally the green one takes precedence. • Carbon credit makes the green H 2 scenario emerges frontrunner utilizing PV solar technology. • Methanol was recognized as the most cost-effective H 2 carrier for storage in Iran. [ABSTRACT FROM AUTHOR]

Combustion of hydrogen-enriched natural gas is a valuable short-term strategy for reducing CO 2 emissions from high temperature industrial heating. This paper presents several experiments on combustion characteristics and the formation of nitrogen oxides. The experiments included hydrogen contents up to 100% and fuel heat inputs up to 75 kW. Water-cooled lances were used to influence the furnace temperature. The analysis includes the distribution of furnace temperatures, the composition of flue gas, the cooling capacity of the lances under steady-state operating conditions, and OH*-chemiluminescence imaging of the near burner region. The presented results demonstrate the dependence of furnace conditions and NO X formation on various factors, such as different air inlet fluxes, furnace temperature, and fuel composition, for constant heat inputs. Efficiency increased by up to 5.5% and significant changes in flame shaped along with a maximum increase in NO X emissions when comparing natural gas to hydrogen was measured at 167%. [Display omitted] • Combustion of hydrogen-enriched natural gas with 0 to 100% H 2 • Experimental analysis of an industrial burner in a steady state, false air-free furnace. • Converged measurements for temperature, flue gas composition and cooling heat fluxes. • Dependence of NO X in mg/kWh on flame shape, temperature, fuel blend and air ratio. • Imaging of self-emitted OH*-chemiluminescence from turbulent jet flames. [ABSTRACT FROM AUTHOR]

Business-as-usual (BAU) cement production is associated with a linear model that contributes significantly to global warming and is dependent on volatile energy markets. A novel circular model is proposed, by adding three power-to-gas system components to current production systems: a calcium-looping (CaL) CO 2 capture unit; water electrolysis for hydrogen and oxygen generation; and a methanation unit for synthetic natural gas (SNG) production. The paper presents the first analysis of the combined industrial-scale operation of these components in a closed loop, where the SNG fuels the cement kiln and the CaL unit, while the O 2 produced feeds it. The circular, hybrid, and BAU models are compared in three feasibility scenarios. It is concluded that the circular model outperforms the other alternatives environmentally, opening a potential pathway for the cement industry to achieve near net-zero CO 2 emissions, reduce energy dependence and improve economic efficiency. [Display omitted] • Innovative circular model proposed for carbon-neutral cement production. • Novel integration of CaL CO 2 capture, water electrolysis and methanation units. • Comparative techno-economic and environmental analysis conducted. • Circular model outperformed current and hybrid models. • Near net-zero CO 2 emissions and increased energy independence achieved. [ABSTRACT FROM AUTHOR]

The transition to sustainable and low-carbon ironmaking processes has necessitated innovative solutions. The most prominent solutions are the establishment of a circular economy by recirculating the iron-rich residues from steelworks and the adoption of hydrogen as a clean reducing agent to mitigate fossil CO 2 emission. One such residue is mill scale, which is generated during steelmaking, casting, and rolling processes. However, the fine particles and easy reoxidation of the mill scale make it difficult to be used directly in iron and steel production without proper compaction. This paper aims to demonstrate the feasibility of mill scale briquetting using organic binders to meet the requirements of hydrogen-based direct reduction. The study will investigate the influence of binder type, binder dosage, moisture content, and compaction pressure on the briquetting process and the briquettes quality. Moreover, the reducibility of optimized briquettes will be examined by hydrogen at 900 °C using a thermogravimetric analyzer coupled with a quadrupole mass spectroscopy (TGA-QMS). The optimal combination for achieving the best mechanical strength and reducibility was a briquette produced with 1% Alcotac® CB6, 1% KemPel, and 2.5% moisture content, compressed at a pressure of 125 kN. • Circular economy is a prominent solution for sustainable ironmaking. • Hydrogen is the way forward to decarbonize the steel industry. • Briquetting of mill scale is a way for its successful recirculation. • Organic binders can successfully be implemented in ironmaking. • Briquette compaction and moisture significantly influences its strength. [ABSTRACT FROM AUTHOR]

In September 2020, the European Union (EU) decided to include the maritime industry into the EU emissions trading system to effectively control carbon emissions from ships, namely the maritime emissions trading system (METS). Various allocation and trading schemes are adopted in practice. This paper investigates a comparison of allocation and trading schemes of the METS from the perspective of liner shipping carriers and regulators, respectively. We explore how to determine the optimal allocation and trading scheme of the METS and how the liner shipping route (LSR) choice decision (following or avoiding the METS) and carbon emissions will be affected. For liner shipping carriers, we use a mixed-integer linear programming model that aims to reduce carriers' costs to formulate our problem. For regulators, we present a bi-level programming model that aims to reduce carbon emissions. In numerical experiments, we further analyze the impact of joining the METS on the scheme choice, LSR choice and emissions by considering the European Economic Area and the Red Sea being covered by the METS. Numerical experiments are provided to show the effectiveness of our proposed models. • Investigate allocation and trading schemes of the maritime emission trading system. • Propose a liner shipping route choice problem. • Develop a mixed-integer linear programming model. [ABSTRACT FROM AUTHOR]

The construction industry's heavy reliance on conventional cement production contributes significantly to global carbon dioxide emissions, prompting the need for eco-friendly building materials. Geopolymers, synthesized from natural materials like clay and fly ash, offer a sustainable alternative to traditional cement. This paper investigates the development of phosphoric acid-activated geopolymers with sanitary ware waste (SWW) as aggregates, aiming to create high-performance, environmentally friendly building materials. Various particle sizes of SWW were incorporated into the geopolymer matrix, revealing a strong relationship between particle size and compressive strength. The inclusion of SWW improved compressive strength, with a notable 83 % increase at 30 % SWW content. Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analyses highlighted the formation of new bonds in the geopolymeric gel, while scanning electron microscopy (SEM) showed microcracks and good adhesion between SWW particles and the geopolymer matrix. Thermal resistance tests demonstrated that SWW-reinforced geopolymers exhibited improved resistance to high temperatures compared to the reference geopolymer. XRD analysis of thermally treated geopolymers revealed the transformation of amorphous phases into stable crystalline phases. SEM/EDX mapping confirmed the presence of silica-rich phases, contributing to the materials' mechanical properties and thermal resistance. This study underscores the potential of SWW-based geopolymers as sustainable, high-performance building materials. [ABSTRACT FROM AUTHOR]

This paper endeavors to utilize the numerical modeling method to evaluate the energy, economic, and environmental performances of a new hybrid PV-FC system for green hydrogen and electricity production. The proposed system consists of photovoltaic panels, fuel cells, an electrolyzer, a converter, and a hydrogen storage tank. A robust techno-enviro-economic (3E) analysis is conducted through comprehensive modeling for the system components using MATLAB/Simulink®. In this validated model, the essential parameters have been calculated: PV plant power, area and efficiency, electrolyzer efficiency, flow rate and power, stack power, area and efficiency, total LCOE of the integrated components, and CO 2 emission reduction. Moreover, the NSGA-II coupled with TOPSIS decision-making approach and Gaussian Process Regression machine learning method with selection kernel function are also utilized as a novel inclusion for the prediction and optimization of the 3E performances of this hybrid system. To obtain a multidimensional view of the optimization, six key decision variables of total stack power, fossil fuel-based generator energy, total CO 2 emissions coming from hydrogen production, total FC system voltage, module area, and number of PV modules have been adopted. The optimization problem encompasses maximizing the total fuel cell stack power and carbon emission reduction, while simultaneously minimizing the total stack area and levelized cost of energy. The simulation outcomes reveal that the stack can reach its maximum output power of 350 kW when operating temperatures are between 40 °C and 55 °C and there are more than 380 cells in the stack. Also, the LCOE was found to be less than $2/kWh for solar radiation above 250 W/m2 and PV outputs reaching 100 W. Further, Increasing FCs from 10 to 400 reduces CO 2 emissions by roughly 13% at 100 °C. Ultimately, the optimal configuration of the system yields stack power of 1589 kW, a total stack area of 269.9 m2, and total CO 2 emission reduction of 1268 ton CO2 , respectively. • Robust 3E analysis using MATLAB-based techno-environmental-economic study. • ML tool using GPR and GA optimization method used for performance optimization. • LCOE is less than $2/kWh for solar radiation above 250 W/m2 and 100 W PV output. • The PVFCEHST model exhibits a high degree of reliability and a robust integrated model. • FC power efficiency reaches 60% when operational temperature is between 40 and 55 °C. [ABSTRACT FROM AUTHOR]

It is well known that solving the greenhouse effect caused by increasing CO 2 emissions is urgent, and CO 2 methanation reaction is a popular research area as one of the effective ways. However, there are great obstacles and challenges to develop catalysts with higher stability and catalytic activity. In order to reduce the activation energy required for methanation reactions, it is expected to introduce another metal into monometallic catalysts to form bimetallic catalysts through the synergistic effect between the bimetallic phases. This paper reviews the advantages of metal-phase combinations for bimetallic catalysts applied to CO 2 methanation. The main synthetic methods used to prepare bimetallic catalysts in recent years are discussed. The effects of bimetallic phase synergy, bimetallic phase structure, metal particle size and dispersion, metal component ratio, and carrier effect on catalyst performance are analyzed. Finally, the challenges and application prospects of bimetallic catalysts for CO 2 methanation are presented. • Hydrogenation mechanisms for combinations of combination of dual active components are analyzed. • The preparation method and auxiliary preparation technology of bimetallic catalyst are discussed. • The synergistic effect between the two metal phases should sometimes be enhanced and sometimes suppressed. • The structure between the two metal phases improves the efficiency of the catalysts. • Different catalyst particle sizes affect product generation in CO2 hydrogenation reactions. [ABSTRACT FROM AUTHOR]

The hydrogen combustion engine (H 2 ICE) is known to be able to burn H 2 , producing no CO 2 emissions and extremely low engine-out NO x eo emissions. In this work, the potential to reduce the NO x eo emissions through the implementation of electric hybridization of an H 2 ICE-equipped passenger car (H 2 -HEV), combined with a dedicated energy management system (EMS) is discussed. Achieving a low H 2 consumption and low NO x eo emissions are conflicting objectives, the trade-off of which depends on the EMS and can be represented as a Pareto front. The dynamic programming algorithm is used to calculate the Pareto-optimal EMS calibrations for various driving missions. Through the utilization of a dedicated energy management calibration, H 2 -HEVs exhibit the potential to decrease the NO x eo emissions by more than 90%, while, decreasing the H 2 consumption by over 16%, compared to a comparable non-hybridized H 2 -vehicle. The present paper represents the initial potential analysis, suggesting that H 2 -HEVs are a viable option towards a CO 2 -free mobility with extremely low NO x eo emissions. • H 2 -HEVs with a dedicated energy management can achieve extremely low NO x eo • Mixed H 2 -HEVs have a superior H 2 -NO x eo trade-off than series and parallel H 2 -HEVs • Mixed H 2 -HEVs lower the NO x eo emissions by 90% and decrease the H 2 consumption by 16% • H 2 -HEV's optimal EMS calibrations for the entire H 2 - NO x eo Pareto front [ABSTRACT FROM AUTHOR]

The sustainability issue in the transportation sector brings the electric vehicle (EV) as a new promising solution for reducing carbon emissions. However, the EV adoption faces issues regarding range, recharging time, and high initial investment. To enhance the adoption, supporting infrastructures should be planned. Therefore, forecasting the growth of EV adoption becomes important to help industries and government in strategic decision making. This paper provides a literature review about forecasting methods in EV ownership, which includes studies from 2011 to March 2023. This will contribute to highlight the current methods and stimulating more developments of forecasting methods related to EV ownership. [ABSTRACT FROM AUTHOR]

[Display omitted] Waste-to-Energy (WtE) technology is the most effective solution for managing non-recyclable wastes through mass burning and energy recovery. Owing to the significant volumes of plastics in China's industrial solid wastes (ISW), a large amount of greenhouse gases (GHG) is generated during the incineration process. Therefore, monitoring GHG emissions from WtE facilities is essential. Owing to the lack of suitable accounting models and characterized fossil carbon fraction (FCF) data, current studies use default values provided by the Intergovernmental Panel on Climate Change's (IPCC), which increases calculation inaccuracies. Therefore, this study established an improved method to accurately account for carbon emissions during solid waste incineration by firstly using radiocarbon dating by accelerator mass spectrometry (AMS) technique to determine the FCF of the solid waste components in China. Monte Carlo analysis was employed to perform the sensitivity analysis, and the results indicated that there was a significant deviation between the measured value and IPCC's default values of FCF, 3.2, 32.48, 93.39, 93.76, 90.49, and 93.8 % for paper, cotton, synthetic textiles, artificial rubber, artificial leather, and plastics, respectively. By replacing coal with ISW in a 2 × 110 t/h circulating fluidized bed boilers, 9.251 × 104 t CO 2 -eq emissions were reduced, and the carbon emission factor reached 0.56 t CO 2 -eq/t waste. This study complements the research gap fossil carbon data of wastes in the IPCC guidelines and provides a more accurate and effective way to calculate carbon emissions during ISW incineration treatment. [ABSTRACT FROM AUTHOR]

Biomass can partially replace fossil fuels for power to reduce CO 2 emissions and save non-renewable resources. In the pulp and paper industry, a waste biomass of calcium lignin was obtained by treating chemo-mechanical pulp (CMP) wastewater with calcium oxide. To investigate waste calcium lignin and its potential use in power generation systems in place of fossil fuels, a basic experiment on calcium lignin gasification was conducted. A model of gasification combined power generation was developed. The results showed that, the gasification temperature was 800 °C, the equivalence ratio (ER) was 0.25, the syngas yield was 78.2 wt%, the lower heating value (LHV) of the syngas was 5.15 MJ/Nm3, and the highest cold gas efficiency (CGE) was 57.84%. In the model, the generated electricity and CO 2 emissions were 1.10 kg/kWh and 0.62 kg CO 2 /kWh, respectively. The use of calcium lignin biomass reduced 35.42% of CO 2 emissions compared to a traditional coal-fired power plant. In addition, the product value-added was 1.17 RMB per kWh, and this was 82.81% higher than that of the 0.64 RMB of traditional coal-fired power plant. [Display omitted] • Production of syngas from the solid waste of calcium lignin by gasification. • Syngas was used for power generation to reduce the use of fossil fuels. • A model was established to investigate the emission reduction effect of CO 2. [ABSTRACT FROM AUTHOR]

• A new capture process of NH3-containing gas treatment with ionic liquids was designed. • MOGA method was employed to optimize the process operational parameters. • The comparison of water scrubbing and IL-based process was carried out. • TPC of enhanced process can be reduced by 32.41 % than water scrubbing. Ammonia (NH 3) emission has caused serious environment issues and aroused worldwide concern. The emerging ionic liquid (IL) provides a greener way to efficiently capture NH 3. This paper provides rigorous process simulation, optimization and assessment for a novel NH 3 deep purification process using IL. The process was designed and investigated by simulation and optimization using ionic liquid [C 4 im][NTF 2 ] as absorbent. Three objective functions, total purification cost (TPC), total process CO 2 emission (TPCOE) and thermal efficiency (η eff) were employed to optimize the absorption process. Process simulation and optimization results indicate that at same purification standard and recovery rate, the novel process can achieve lower cost and CO 2 emission compared to benchmark process. After process optimization, the optimal functions can achieve 0.02726 $/Nm3 (TPC), 311.27 kg CO 2 /hr (TPCOE), and 52.21% (η eff) for enhanced process. Moreover, compared with conventional process, novel process could decrease over $ 3 million of purification cost and 10000 tons of CO 2 emission during the life cycle. The results provide a novel strategy and guidance for deep purification of NH 3 capture. SYNOPSIS: This work guides to optimization of the process for NH 3 capture and NH 3 resource recovery based on ionic liquids. [Display omitted] [ABSTRACT FROM AUTHOR]

Considering the escalating global warming and its severe consequences, the exploitation of hydrogen, an eco-friendly energy carrier, is gaining great interest. This paper comprehensively reviews the most common hydrogen production, storage, transportation and utilization processes, while their effectiveness is explored from energy, water, economic and environmental perspectives. Their main characteristics, advantages, shortcomings and challenges are discussed as well. The research reveals that the hydrogen's water footprint, energy consumption, carbon emissions, and cost vary significantly depending on the specific technologies used throughout its life cycle, from production to end use. For instance, fossil fuel-based hydrogen production methods, such as steam methane reforming, offer elevated energy performance and cost-effectiveness, but have a significant carbon footprint. In contrast, water electrolysis is environmentally friendly, but requires more water and has lower energy efficiency. Besides, high-pressure containers are the preferred method for hydrogen storage, while liquid and solid storages are better suited for high-energy-density applications. Regarding hydrogen transportation, pipelines are effective over long distances, whereas tankers are convenient for short distances. Furthermore, fuel cells are more energy, carbon and water efficient when using hydrogen as fuel, but they are generally more expensive than internal combustion engines. [Display omitted] • Hydrogen production, storage, transportation and utilization methods are reviewed. • Their energy efficiency, water use, cost, and environmental impact are explored. • Key recommendations to boost the utilization of hydrogen systems are outlined. • Fossil fuel-based technologies are more energy-efficient and cost-effective. • Renewable-based processes are more environmentally friendly but water-intensive. [ABSTRACT FROM AUTHOR]

In the light of the recent standards proposed by the European Union in terms of CO 2 emissions for the internal combustion engines, the attention is increasingly focused on e-fuels, among which the renewable-produced hydrogen. The present paper proposes a numerical methodology for 3D-CFD in-cylinder simulations of hydrogen-fuelled internal combustion engines. The proposed framework includes in-house developed models for ignition, knock and heat transfer and it is based on the G-equation combustion model. The predictive capabilities of the methodology are validated against experimental data on a single-cylinder naturally-aspirated diesel engine converted for spark-ignited hydrogen operation. Specifically, H 2 is direct injected thanks to two injectors installed on the cylinder head. Moreover, a spark plug is added and the compression ratio is lowered. The investigated conditions cover different revving speeds (from 1500 rpm to 3000 rpm) and equivalence ratios (0.4, 0.6 and 0.8). The satisfying agreement between numerical results and experimental counterparts paves the way to future studies (e.g. on emission modelling) and engine optimization. • Simplification of geometry of injectors preserved the accuracy of the results. • Mixture homogeneity in swirling flow field is influenced by injected amount of fuel. • Flamelet combustion model G equation is reliable for engine combustion simulation. • Wide range of operating conditions can be simulated with same numerical setup. [ABSTRACT FROM AUTHOR]

A cogeneration of power and hydrogen plant driven by clean solar energy is developed, analyzed and optimized in this paper. For hydrogen production in the suggested plant, a thermochemical cycle with Vanadium–Chlorine (VCl) working pair is integrated with parabolic trough collectors and an auxiliary heater to provide the required temperature level. For power generation, however, an organic Rankine cycle is applied to generate electricity from extra heat which is not utilized in VCl thermochemical cycle. For performance improvement of developed cogeneration framework, nanoparticles are applied for enhancing thermal behavior of collector field. A comprehensive analysis is conducted to determine system performance enhancement with nanufluid as compared to basefluid case in thermal loop of collectors. Thermodynamic investigations paying more attention on exergy evaluations are carried out along with economic considerations to assess system performance. Furthermore, to address the proposed plant's environmental impacts, the overall plant's performance and carbon dioxide emission reduction are estimated. Parametric appraisal is implemented to specify operating factor impacts on power and hydrogen production and unit cost of product. Also, multi-objective optimization is performed based on cost and efficiency indices. It is found that, addition of nanoparticles to basefluid can enhance system performance roughly by 3 − 5 %. The nanofluid based framework attains efficiency of 40.16% and unit product cost of 39.93 $/GJ under optimum conditions. Finally, based on the findings of the environmental impact analysis, the designed system in cogeneration mode was able to mitigate CO 2 emissions by 1173 kg/h. • Parabolic trough solar collectors are coupled with thermochemical hydrogen production. • Nanoparticles are used to enhance thermal performance of solar loop. • Improvement of 3–5% is found with nanoparticles' utilization on overall system. [ABSTRACT FROM AUTHOR]

One of the reasons why renewable energies are so attractive compared to fossil fuels is their low environmental impact. In addition, geothermal power plants contribute tremendously to sustainable energy generation for cities despite their lower energy efficiency than fossil fuel plants. The multi-heat recovery will eliminate the applicability defect mentioned. Therefore, this paper studies a novel tri-generation schema with the maximum use of heat loss through a multi-heat recovery technique in two principal processes, namely waste heat-to-power and power-to-H 2 and -purified water. A double-flash binary cycle, Rankine cycle, electrolyzer unit, and reverse osmosis desalination system all play a part in the creation of this system. The technical feasibility of the system is scrutinized based on energy-exergy, environmental, sustainability, and exergoeconomic metrics and bi-objective optimization. Generally, 1st separator pressure made the strongest effect on the measured variables among decision variables. The increase in this parameter led to an upward-and-downward behavior of the net electricity and exergetic efficiency; while the cost of products experienced a converse trend. Also, the produced H 2 and purified water together with the tri-generation gain output ratio augmented. Changes were not observed in net electricity and purified water with the change in 2nd separator pressure, but the H 2 production rate changed significantly. Through bi-objective optimization, net electricity, purified water production rate, and total investment cost rate also significantly increase. Based on the optimum design mode, the CO 2 emission rate and the sustainability index are higher than under the base case design. • Using multi-heat recovery technique in two principal processes, namely, waste heat-to-power and power-to-H2 and -purified water. • Evaluation of system indices based on energy-exergy and exergoeconomic metrics and bi-objective optimization. • Exergetic efficiency, TGOR, and the cost of products improved by 5.19%, 109.52%, and 8.54%, separately, thanks to bi-objective optimization. [ABSTRACT FROM AUTHOR]

Multigenerational energy conversion plants are one of the most promising solutions for tackling environmental challenges and making efficient use of energy sources. In this regard, a newly designed multigeneration plant integrated with a methane-based Brayton cycle, a steam Rankine cycle, a supercritical CO 2 -based Brayton cycle, a multi-effect desalination process, a PEM unit, a domestic water heater process, and two thermoelectric generators is integrated, proposed and analyzed. The thermodynamic and environmental assessments of the developed paper are conducted and examined with energy and exergy efficiencies as well as CO 2 emission rate. Similarly, a parametric study is executed and reported, by the way, to define the impact of the various significant factors on the developed plant's efficiency. In the end, the CO 2 emission rate is determined and compared according to different energy conversion plants. In light of the analysis results, the net power, hydrogen, and freshwater production capacities of the reference study are calculated to be 1336 kW, 0.002004 kgs−1, and 0.954 kgs−1, respectively. Additionally, it is found that the developed study's energetic and exergetic performances are 55.76% and 52.17%. According to emission analysis results, the multigeneration system emits 272.2 k g / M W h less CO 2 emissions than the single energy conversion system. • A newly designed multigeneration plant is suggested. • Combination of a superciritical CO 2 based Brayton cycle is proposed. • Thermodynamic and environmental analysis of the multigeneration plant is conducted. • Freshwater, hydrogen, power and heating purposes are fulfilled. • The overall energy and exergy efficiencies are 55.76% and 52.17%, respectively. [ABSTRACT FROM AUTHOR]

The pressure of the global sustainability problem is growing faster than ever after the social and economic havoc wreaked by the pandemic, as well as the present time nearing to the 2050 net zero carbon goal. In 2021 the steel industry had a turnover of around €125 billion and was directly responsible for providing at least 300000 jobs. In 2022, it was responsible for roughly 5% of CO 2 emissions in the EU and 7% globally, and was responsible for at least 20278 injuries and 90 deaths. Environmental solutions for mitigating negative consequences of the steel industry exist such as hydrogen-based steelmaking, carbon capture, utilisation and storage and electrolysis, whilst safety regulations and personal protective equipment have been used to improve safety. However, little has been done to combat the problem using the most powerful emerging technology of the fourth industrial revolution, artificial intelligence. In particular, computer vision has already shown great competence in a range of applications related to steelmaking, but without seriously considering sustainability, resulting in limited awareness of the potential benefits computer vision can bring to industry. A lack of this awareness leads to missed opportunities for sustainable development. This paper aims to address the gap in research that discusses computer vision capabilities for enhancing the sustainability of steel production by providing a literature review covering recent advances in computer vision, as well as an industry 4.0 approach for integrating computer vision systems with steelworks. Research presented here successfully exposes the untapped potential of computer vision in the steel industry and paves the way for future developments by exhibiting a blueprint for simultaneously elevating sustainability and technological advancement. [ABSTRACT FROM AUTHOR]

In this paper, wind resource availability was determined by analyzing the meteorological wind energy potential at the hub height of wind turbines. The wind resource potential was identified in specific geographic locations. Technical factors, such as siting requirements and resource availability, were taken into account in the investigation. The economic potential was calculated for each area of Algeria, considering overall losses. Subsequently, the potential for reducing fossil fuel usage was determined through wind to hydrogen estimation. The main components utilized in this work were a Vestas-90 wind turbine (V90–2.0 MW) and an alkaline electrolyzer. The analysis employed a Geographical Information System (GIS) tool. The results demonstrate Algeria's significant potential for wind to hydrogen production, estimated at 1.093 Gt/year without constraints, and reduced to 1.066 Gt/year when considering constraints. The levelized cost of wind to hydrogen production in Algeria varies between 1.51 and 15.37 US $/kg, depending on the chosen wind turbine. The wind to hydrogen production potential identified has the capacity to replace the entire current fossil fuel consumption in the transportation sector, which amounts to 5.28 Mt H 2 /year. The utilization of wind to hydrogen in the transport sector results in a significant reduction of CO 2 emissions, with a calculated avoidance of 45.69 Mt compared to the use of gasoline and diesel. Hydrogen produced from wind energy resources also could be used to support other sectors, including residential, agricultural, and industry in Algeria. • GIS-Based approach is used to evaluate the potential for wind to hydrogen production in Algeria. • The total wind to hydrogen potential in Algeria, when considering constraints, is estimated at 1.066 Gt/year, covering an area of 730,719 km2. • The levelized cost of wind to hydrogen production in Algeria ranges between 1.51 and 15.37 US $/kg, depending on the selected wind turbine (V90–2.0 MW). • The CO 2 emissions avoided in the transport sector are 45.69 Mt compared if the same amount of gasoline and diesel used. [ABSTRACT FROM AUTHOR]

Hydrogen is a type of clean secondary energy, and the hydrogen energy supply is vital to regional energy development. Guangdong is at the forefront of hydrogen energy deployment in China, and aims to achieve peak carbon by 2030. However, hydrogen production research is challenging due to complex technical routes, technical maturity levels, life-cycle carbon emissions, and costs. Multi-time-scale research is necessary to explore optimal production paths and their contributions to CO 2 emission reduction. This study discussed key technologies and the technical maturity of five hydrogen production routes: production from industrial byproducts and coal, wind, hydro-, and photovoltaic power. Policy scenarios were designed to investigate the potential of these routes and technology deployment intensity under medium- and long-term scenarios. This paper proposes a roadmap for hydrogen development and provides a reference for hydrogen production planning in Guangdong. This methodology can be applied in other regions for hydrogen energy development research. • Key technology maturity of the hydrogen production routes was evaluated. • Roadmap of hydrogen production in Guangdong Province was designed. • A method for research of hydrogen supply scenarios was proposed. [ABSTRACT FROM AUTHOR]

In view of the huge contribution of transportation to global greenhouse gas emissions, it is imperative to embrace more carbon-efficient transportation modes to support our environmental goals. However, few studies offer empirical evidence to evaluate the potential of shifting transportation model for carbon emissions reduction. This paper, aiming at addressing this gap, conducts an empirical study to assess the CO2 emissions reduction through modal shift from road to waterway transport (MSRW). It utilizes primary data collected from more than 200 voyages of 92 enterprises through one national pilot project on CO2 emission reduction in the Quzhou region initiated by the Chinese central government. Specifically, it employs empirical analysis based on bottom-up methodologies to investigate the potential for CO2 emission reduction through MSRW. The results reveal that MSRW can aid to benefit 45,907 tons CO2 emission reduction from the modal shift within the study scope. When considering factors such as distance and voyage density, it provides new quantitative insights into the advantages of water transport over road transport in terms of CO2 emission reduction under different scenarios. Consequently, this study makes new contributions to the quantification of the benefits that an investigated region/city can derive from transport modal shift. It thereby lays the groundwork for effective cost-benefit analysis and policy implementation toward cleaner transportation. • Use of a hybris of energy consumption approach from a new analysis perspective that consider multiple-dimensional MSRW. • Provide a new research method to enable the quantification of the carbon emissions of an entire transport chain in detail. • Provides a solution to the evaluation of the effect of the implementation of transport policies on carbon emissions. • Investigate the MSRW to stimulate cost-benefit analysis and transport policy implementation towards clean transportation. [ABSTRACT FROM AUTHOR]

Renewable energies are available as clean sources to replace fossil fuels. Providing continuous power without compromising the environment through hybridizing solar and biomass source is one of the promising solutions. This paper seeks to address thermodynamic, economic, and environmental analysis of a multi-generation system with the aim of supplying heating, cooling, electricity, fresh-water, and hydrogen. To do this, the considered system is divided into on-peak, mid-peak, and off-peak periods and modeled based on the consumption pattern at different hours of the day and night. Due to the availability of renewable energy during peak consumption periods, biomass, solar, and hybrid biomass-solar energies are used as energy sources. This leads to a reduction in biomass consumption and carbon dioxide emissions through storing approximately 10 tons of biomass during the day. A sensitivity analysis of the factors affecting the system's function indicated that a growth in solar radiation from 600 to 1000 W/m2, results in a 35% improvement in exergy efficiency, a 2.7% raise in the total cost rate, and a 32.4% drop in CO 2 emissions of the system. Moreover, by changing the biomass flow rate from 0.5 to 1.5 kg/s, the exergy efficiency and total cost rate improved by 9.28%, 1.3%, respectively, and the CO 2 emissions rate increased from 0.41 to 1.14 tons/MWh. In addition, focusing on addressing economic and environmental concerns, the optimization of the proposed hybrid system is performed in two categories of objective functions. In the second category optimization, exergy efficiency, fresh water production, total cost rate and CO 2 emissions are determined as 31.75%, 74.75 kg/s, 324.60 $/h and 3.55 tons/MWh, respectively. [Display omitted] [ABSTRACT FROM AUTHOR]

Ammonia (NH 3)-coal co-firing is a promising technology to reduce CO 2 emission. The strong interaction between ammonia and coal during the co-pyrolysis has a considerable impact on nitrogen migration and transformation and will further affect the NO x formation. In this paper, to investigate the effect of the volatile fraction on the migration of N, Shenhua (SH) and Wanxiang (WX) bituminous coals were devolatilized to different levels in the first pyrolysis step and were then co-pyrolyzed with NH 3 in the second pyrolysis step. It is found that the migration of N from the gas to solid is more significant than the release of N with the volatile, especially when the temperature in the first pyrolysis step is low. Given the same pyrolysis condition, WX coal/char has more oxygen-containing functional groups than SH, thus the increase of N content during the NH 3 /coal co-pyrolysis is more significant for WX. The absolute contents of pyridinic N (N-6), pyrrolic N (N-5), and protonated pyridinic N or quaternary N (N-Q) are calculated before and after the co-pyrolysis step according to the results of elemental analysis and X-ray photoelectron spectroscopy. An obvious increase of N-6 is observed in chars with lower degree of devolatilization for both coals. A transformation of N-5 to other types of N is observed for SH coal/char. In contrast, the transformation of N-5 is less obvious for WX, which is due to the presence of alkali metal chlorides in WX. Moreover, WX coal/char has less aromatic structure and more aliphatic groups, which promotes the transformation of N from NH 3 to N-5. Based on these results, possible reaction pathways of N migration and transformation during NH 3 /coal co-pyrolysis are proposed. • Migration of N during ammonia-coal co-pyrolysis are investigated. • Migration of N onto char is more significant than release of N from char. • N that migrates from NH3 to char mainly exists as pyridinic N and pyrrolic N. • Possible reaction pathways of N migration are proposed. [ABSTRACT FROM AUTHOR]

A promising way to rapidly and economically cut back CO 2 emissions of steam methane reforming is the electrification of the gas-fired methane reforming process. However, there is a challenge to effectively bringing the required heat to the process, typically a hot stream gas, from an electrical source. This paper presents the architecture of a novel microreactor integrated into an electrically heated setup to perform methane reforming. Experimental assessment is presented, beginning with the syngas composition during dry, mix and ensuing steam methane reforming at 900 °C ± 2 °C, 71,000 h−1 GHSV, and steam to carbon ratio (S/C) of 2. It showed H 2 /CO ratios close to the calculated equilibriums and fast transient behaviours allowing reduced start-up and cool-down time for industrial applications compared to traditional reformers. The performance of the reactor was then investigated for a range of temperatures, mass flow, pressure, and steam-to-methane ratio. The experiments revealed a CH 4 conversion varying between 82% and 98% following anticipated trends. The reactor was operated continuously for 170 h at 900 °C, S/C of 2, and 71,000 h−1 GHSV with limited degradation in its performance, mainly caused by carbon deposit on the catalyst. Finally, a cumulative of 400 h of test on the microreactor has demonstrated no apparent structural degradation or abnormal channel obstruction. • Development of 3D-printed electrically-heated microreactors. • High methane conversion demonstrated at high GHSV. • Microreactor successfully tested for 170 h of operation. [ABSTRACT FROM AUTHOR]

Biomass-derived power generation presents various potential benefits compared to conventional fossil fuel-based power generation. Also, efficient integration of energy systems leads to higher sustainability and effectiveness. This paper presents a biomass-fueled energy system with two open and closed Brayton cycles in the waste heat, of which a humidification and dehumidification system is implemented. The usage of four different biomasses as the fuel of the gasifier is tested and put to comparison from the aspects of thermodynamics, economics, and environment. The Grassman diagram for each layout is presented to signpost the exact point of highest exergy destruction and irreversibility. The optimization based on machine learning techniques is conducted to pinpoint the exact optimum operational conditions. The results indicate that wood offers more sustainability compared to other biomasses, and the amount of energy efficiency, exergy efficiency, and freshwater flow rate produced for Wood biomass in the proposed system are 75.81 %, 36.98 %, and 0.4091 kg/s, respectively. Also, two optimization scenarios have been done for this study. In the initial optimal solution finding, effectivness, unit product cost, and carbon dioxide emission index are equal to 45.9 %, 12.6 $/GJ, and 0.7161 kg/kWh, correspondingly. In the latter scenario, the effectiveness, net power production, and production unit cost of products are equal to 45.9 %, 6580 kW, and 12.61 $/GJ, respectively. • A novel Tri-generation system based on supercritical CO 2 cycle and HDH cycle. • Energy, exergy, techno-economic, and environmental analyses are carried out. • Multi-objective optimization using Machine learning Algorithms is done. • Maximum exergy efficiency is obtained to be 40.39 % for MSW. • The minimum production unit cost of products is obtained to be 14.06 $/GJ for MSW. [ABSTRACT FROM AUTHOR]