Modeling of the effect of hydrogen injection on blast furnace operation and carbon dioxide emissions

The effect of hydrogen injection on blast furnace operation and carbon dioxide emissions was simulated using a 1D steady-state zonal model.The maximum hydrogen injection rate was evaluated on the basis of the simulation of the vertical temperature pattern in the blast furnace with a focus on the thermal reserve zone.The effects of blast temperature and oxygen enrichment were also examined to estimate coke replacement ratio,productivity,hydrogen utilization efficiency,and carbon dioxide emission reduction.For blast temperature of 1200℃,the maximum hydrogen injection rate was 19.0 and 28.3 kg of H_(2)/t of hot metal(HM)for oxygen enrichment of 2vol%and 12vol%,respectively.Results showed a coke replacement ratio of 3-4 kg of coke/kg of H_(2),direct CO_(2) emission reduction of 10.2%-17.8%,and increased productivity by up to 13.7%depending on oxygen enrichment level.Increasing blast temperature further reduced the direct CO_(2) emissions.Hydrogen utilization degree reached the maximum of 0.52-0.54 H_(2)O/(H_(2)O+H_(2)).The decarbonization potential of hydrogen injection was estimated in the range from 9.4 t of CO_(2)/t of H_(2) to 9.7 t of CO_(2)/t of H_(2).For economic feasibility,hydrogen injection requires revolutionary progress in terms of low-cost H_(2) generation unless the technological change is motivated by the carbon emission cost.Hydrogen injection may unfavorably affect the radial temperature pattern of the raceway,which could be addressed by adopting appropriate injection techniques.

Carbon Dioxide Emissions by the Transportation Sector and Its Impact on Health in the Kathmandu Valley, Nepal

Air pollution is one of the leading cause of death for underdeveloped as well as developed countries. In 2011, the air pollution was the second leading cause of death in one of the main hospitals of the Kathmandu Valley, Nepal, and it was the third leading cause in the United States. Burning fossil fuels for transportation was one of the major causes. Among various impacts of the air pollution, COPD （chronic obstructive pulmonary disease） was one of the main consequences. In the 570 km2 Kathmandu Valley, vehicle registration was increased from 45,871 in 1990/1991 to 570,145 in 2010/2011, an increase of over 12-fold over 20 years. The vehicle registration and number of COPD patients＇ data were collected from various government divisions. In addition, the average daily travel distance and fuel mileage data were collected with a survey with residents of the Kathmandu Valley. This paper calculates the amount of carbon dioxide （CO2） emissions by transportation sector and determines correlation between CO2 emissions and COPD patients. Results show that there was a very high level of CO2 emissions, and it was positively correlated with the number of COPD patients in the valley.

Power industry to reduce sulfur dioxide emissions

China has published a stricter emission standard for thermal power plants in order to help reduce the power industry's sulfur dioxide emissions by over six

A hefty target of reducing the intensity of carbon dioxide emissions

At the end of January, China formally handed over the report on pollution reduction targets to the United Nations.

Tracking Transfer of Carbon Dioxide Emissions to Countries along the Silk Roads Through Global Value Chains

The Belt and Road Initiative(BRI)has aroused rich discussions about the possible increase in carbon dioxide emission under the arduous global carbon dioxide emission reduction task.Adopting the methods of input-output technique and complex network ana-lysis,we first construct a fairer method to trace carbon dioxide emission transfer based on global value chains,then trace the source of carbon dioxide emission transfer to the Silk Roads countries with a long-term multiple regional input-output database.We find that,first,after the proposal of the BRI,the total direct carbon dioxide emissions of the Silk Roads countries and China’s proportion of carbon dioxide emission transfer to the other Silk Roads countries have both declined.Second,the Silk Roads countries are generally the net receivers of carbon dioxide emission transfer,and the inflow is mainly distributed in Southeast Asian countries and core countries in other sub-regions.Then,the transfer of carbon dioxide emission accepted by the Silk Roads countries comes mostly from large developing countries,such as China,Russia,and India,and developed countries,such as the United States,Japan,and Germany.The products are mainly concentrated in energy and chemical industries,as well as heavy industries,such as mining and quarrying,and metal products.We suggest that,due to the high degree of spatial and industrial concentrations of carbon dioxide emission transfer,it is necessary to make targeted policies for these countries and industries to reduce these transfers.

Indian Solar Panel Initiatives in Reducing Carbon Dioxide Emissions

Environmental degradation and the emission of greenhouse gases particularly carbon dioxide have expanded problems to human wellness and to the atmosphere. The second-most populated country in the globe, India, is among the primary users of conventional resources, which leads to global warming. The growth rate is anticipated to raise more before 2050, which will cause the brisk industrial expansion and rising energy demand to both increases. In order to reduce carbon emissions and meet energy requirements, many countries use alternate usage of renewable energy particularly solar energy. In this review we aim to study solar panel schemes initiated by India, mainly focusing on National Solar Mission. This study also reviews the present solar installed capacity, solar panel scheme 2022, and initiatives and outcomes of solar panels in residences and offices. This study reviewed that by using solar panel resources, the (MNRE) Ministry of New and Renewable Energy hopes to help the Indian Government reach its purpose of 100 GW solar installed capacity by end of 2022. Despite having an amazing 40 GW of solar power installed capacity till December 2021, India is still far from reaching its own goal of 100 GW by March 2023 as per NSM. In essence, this means that India will need to change a few of its ongoing plans further.

Economic Growth,Industrialization,Trade,Electricity Production and Carbon Dioxide Emissions:Evidence from Ghana

The study scrutinized correlation between electricity production,trade,economic growth,industrialization and carbon dioxide emissions in Ghana.Our study disaggregated trade into export and import to spell out distinctive and individual variable contribution to emissions in Ghana.In an attempt to investigate,the study used time-series data set of World Development Indicators from 1971 to 2014.By means of Autoregressive Distributed Lag(ARDL)cointegrating technique,study established that variables are co-integrated and have long-run equilibrium relationship.Results of long-term effect of explanatory variables on carbon dioxide emissions indicated that 1%each increase of economic growth and industrialization,will cause an increase of emissions by 16.9%and 79%individually whiles each increase of 1%of electricity production,trade exports,trade imports,will cause a decrease in carbon dioxide emissions by 80.3%,27.7%and 4.1%correspondingly.In the pursuit of carbon emissions’mitigation and achievement of Sustainable Development Goal(SDG)13,Ghana need to increase electricity production and trade exports.

Unearthing the impact of urban sprawl on transport carbon dioxide emissions:Fresh evidence from 274 Chinese cities

Urban sprawl has been a prevailing phenomenon in developing countries like China,potentially resulting in significant carbon dioxide(CO_(2))emissions from the transport sector.However,the impact of urban sprawl on transport CO_(2) emissions(TCEs)is still not fully understood and remains somewhat rudimentary.To systematically investigate how urban sprawl influences TCEs,we employ panel regression and panel threshold regression for 274 Chinese cities(2005-2020),and obtain some new findings.Our results affirm that the degree of urban sprawl is positively associated with TCEs,and this holds true in different groups of city size and geographical region,while significant heterogeneity is observed in terms of such impact.Interestingly,we find urban sprawl nonlinearly impacts TCEs—with an equal increase in urban sprawl degree,TCEs are even lower in cities with larger population size and better economic condition,particularly in East China.Furthermore,the low-carbon city pilot policy shows potential in mitigating sprawl's impact on TCEs.Drawing on our findings,we argue that to achieve the target of TCEs reduction in China by curbing urban sprawl,more priority should be placed on relatively small,less developed,and geographically inferior cities for cost-efficiency reasons when formulating future urban development strategies.

Comparison and assessment of carbon dioxide emissions between alkali-activated materials and OPC cement concrete

Geopolymer concrete(GPC)has been developed as a sustainable alternative to traditional cement-based concrete using industrial waste materials.Thus,reducing greenhouse gas emissions in concrete production can be expected.This study employed the life cycle assessment(LCA)method to evaluate geopolymer concrete's cost and life-cycle carbon dioxide(CO_(2))emissions.Moreover,the critical transportation radius of the geopolymer is estimated.Then,evaluation results were compared with ordinary Portland cement(OPC),considering three concrete construction methods:cast-in-place,ready-mixed,and precast.In particular,the service life of two types of concrete in sulfuric acid environments is considered.Compared with OPC concrete,the results show that geopolymer concretes can significantly reduce the cost and CO_(2)emissions when one or a small amount of alkali activator is used or alkali-containing materials are used to replace some alkali activators.However,the advantages would be reversed by the rising alkali dosages,which account for cost increases and carbon emissions.When considering the service life in special environments,geopolymer concrete in sulfuric acid environments corresponds to fewer carbon emissions,94%e97%decreased compared with OPC concrete.Finally,compared with OPC concrete,the newly developed limestone calcined clay cement(LC3)avoids high-temperature calcination and dramatically reduces carbon dioxide emissions.Compared to OPC concrete,LC3 concrete has a 19%reduction in CO_(2)emissions.And geopolymer concrete that takes alkali-activate materials for superseding alkalis also produces less carbon dioxide emissions.In particular,CO_(2)emissions from FA-SF geopolymer concrete are approximately 50%lower than OPC concrete.In addition,the use of alkali activators significantly weakens the cost advantage of geopolymers.But after accounting for waste disposal costs,the average net cost of fly ash-based geopolymer concrete can be more than 30%lower than that of OPC concrete.The average net cost of slag-based geopolymer concrete is 7%e45%lower than that of OPC concrete.The findings of this work provide the basis for further development of geopolymer concretes obeyed environmental protection.

Relationship between Urban Industrial Land Use Size and Sulfur Dioxide Emissions:Evidence from 294 Cities in China

Although the relationship between the size of urban industrial land use and pollutant emissions has been widely discussed from different perspectives(e.g.,the scale and crowding effects),the results of various studies have revealed positive,negative,and combined impact relationships.However,how the expansion of urban industrial land use affects SO_(2) emissions remains unknown.We need to clarify this relationship in order to facilitate the realization of China’s pollution reduction and emission reduction goals.This study used the panel data from 294 cities spanning from 2011 to 2019 to construct a spatial econometric model.The objective was to explore the correlation between the scale of urban industrial land and sulfur dioxide emissions in China.The results show that a large scale of urban industrial land use corresponds to lower sulfur dioxide emissions per unit of industrial added value.By gaining a deeper understanding of the relationship between the scale of urban industrial land use and sulfur dioxide emissions,policymakers can further reduce pollutant emissions by rationalizing the planning of urban industrial land use and industrial layout.In addition to promoting industrial agglomeration and economies of scale in cities with extensive industrial land use,this strategy can support the development of efficient and environmentally friendly industries in areas with limited industrial land use.Optimizing the technology and encouraging the development of green industries can help reduce environmental pollution and promote sustainable urban development.

Road life-cycle carbon dioxide emissions and emission reduction technologies:A review

Carbon dioxide(CO_(2))emissions from the road sector have attracted increasing attention in current years.This paper attempted to provide a systematic review of the existing research efforts on road life-cycle CO_(2)emissions by analyzing the system’s boundary division,identifying the CO_(2)emission contributions of each life-cycle phase,listing major emission contributors,exploring related emission reduction technologies,and giving directions for future development.The research showed that the road life cycle is usually divided into five phases:material production,construction,use,maintenance and end-of-life(EOL)phases.The use phase and the initial construction stage(including material production and construction phases)contributed the most CO_(2)emissions during the road life cycle.In detail,the production of cement,asphalt and steel were the three main emission contributors in the material production phase.The pavement roughness,albedo,and concrete carbonation were the main factors affecting emissions in the use phase.In addition,emission reduction technologies such as using recycled materials and recycling techniques,lowering mixing temperature,and equipment energy substitution were commonly used to reduce emissions from material production and construction phases.The application of emerging technologies such as carbon capture and storage,carbon sink,and the use of hydrogen,solar and photovoltaic in the road sector may have emission reduction potentials and should be highlighted more in future studies.

The prospect of natural gas hydrate(NGH)under the vision of Peak Carbon Dioxide Emissions in China

To achieve the goals of Peak Carbon Dioxide Emissions and Carbon Neutrality,China's energy system will continue to accelerate the transition to a clean and low-carbon one.As the cleanest fossil fuel,natural gas is regarded as an inevitable choice for China to build a clean,safe,efficient,and low-carbon energy system and fulfill the goal of“double carbon”.However,the domestic conventional natural gas supply remains rigid while the stimulation of unconventional natural gas is still limited.If we have a firm grip on the principal line of“understanding the ocean–developing resources–ensuring security”to realize the large-scale development of 85 trillion square meters of NGH in the South China Sea,then we could not only greatly reduce China‘s foreign dependence on natural gas,but also guarantee the safety of China‘s natural gas multi-path supply and safeguard the sovereignty of the South China Sea.Thus,the goal of Peak Carbon Dioxide Emissions and Carbon Neutrality can be achieved in no time.

A deep neural network based model for the prediction of hybrid electric vehicles carbon dioxide emissions

Hybrid electric vehicles(HEV)are nowadays proving to be one of the most promising technologies for the im-provement of the fuel economy of several transportation segments.As far as the on-road category is concerned,a wise selection of the powertrain design is needed to exploit the best energetic performance achievable by a HEV.Amongst the methodologies developed for comparing different hybrid architectures,global optimizers have demonstrated the capability of leading to optimal design solutions at the expense of a relevant compu-tational burden.In the present paper,an innovative deep neural networks-based model for the prediction of tank-to-wheel carbon dioxide emissions as estimated by a Dynamic Programming(DP)algorithm is presented.The model consists of a pipeline of neural networks aimed at catching the correlations lying between the de-sign parameters of a HEV architecture and the main outcomes of the DP,namely powertrain feasibility and tail pipe CO_(2) emissions.Moreover,an automatic search tool(AST)has been developed for tuning the main hyper-parameters of the networks.Interesting results have been registered by applying the pipeline to three databases related to three different HEV parallel architectures.The capability of the pipeline has been proved through an extensive testing campaign made up by multiple experiments.Classification performances above 91%as well as average regression errors below 1%have been achieved during an extensive set of simulations.The presented model could hence be considered as an effective tool for supporting HEV design optimization phases.

Driving factors of carbon dioxide emissions in China： an empirical study using 2006-2010 provincial data

The rapid urbanization of China has increased pressure on its environmental and ecological well being. In this study, the temporal and spatial profiles of China＇s carbon dioxide emissions are analyzed by taking heterogeneities into account based on an integration of the extended stochastic impacts using a geographically and temporally weighted regression model on population, affluence, and technology. Population size, urbanization rate, GDP per capita, energy intensity, industrial structure, energy consumption pattern, energy prices, and economy openness are identified as the key driving factors of regional carbon dioxide emissions and examined through the empirical data for 30 provinces during 2006-2010. The results show the driving factors and their spillover effects have distinct spatial and temporal heterogeneities. Most of the estimated time and space coefficients are consistent with expectation. According to the results of this study, the heterogeneous spatial and temporal effects should be taken into account when designing policies to achieve the goals of carbon dioxide emissions reduction in different regions.

Current situation of carbon emissions and countermeasures in China's ironmaking industry

The iron and steel industry(ISI) involves high energy consumption and high pollution. ISI in China, a leading country in the ISI,consumed 15% of the country’s total energy and produced more than 50% of the global ISI’s carbon emissions. Therefore, in the context of global low-carbon economy and emission reduction requirements, low-carbon smelting technology in the ISI has attracted increasingly more attention in China. This review summarizes the current status of carbon emissions and energy consumption in China’s ISI and discusses the development status and prospects of low-carbon ironmaking technology. The main route to effectively reducing carbon emissions is to develop a gas-based direct reduction process and replace sintering with pelletizing, both of which focus on developing pelletizing technology. However,the challenge of pelletizing process development is to obtain high-quality iron concentrates. Consequently, the present paper also summarizes the development status of China’s mineral processing technology, including fine-grained mineral processing technology, magnetization roasting technology, and flotation collector application. This paper aims to provide a theoretical basis for the low-carbon development of China’s ISI in terms of a dressing–smelting combination.

Change trend of natural gas hydrates in permafrost on the Qinghai-Tibet Plateau(1960-2050)under the background of global warming and their impacts on carbon emissions

Global warming and the response to it have become a topic of concern in today’s society and are also a research focus in the global scientific community.As the world’s third pole,the global warming amplifier,and the starting region of China’s climate change,the Qinghai-Tibet Plateau is extremely sensitive to climate change.The permafrost on the Qinghai-Tibet Plateau is rich in natural gas hydrates(NGHs)resources.Under the background of global warming,whether the NGHs will be disassociated and enter the atmosphere as the air temperature rises has become a major concern of both the public and the scientific community.Given this,this study reviewed the trend of global warming and accordingly summarized the characteristics of the temperature increase in the Qinghai-Tibet Plateau.Based on this as well as the distribution characteristics of the NGHs in the permafrost on the Qinghai-Tibet Plateau,this study investigated the changes in the response of the NGHs to global warming,aiming to clarify the impacts of global warming on the NGHs in the permafrost of the plateau.A noticeable response to global warming has been observed in the Qinghai-Tibet Plateau.Over the past decades,the increase in the mean annual air temperature of the plateau was increasingly high and more recently.Specifically,the mean annual air temperature of the plateau changed at a rate of approximately 0.308-0.420℃/10a and increased by approximately 1.54-2.10℃in the past decades.Moreover,the annual mean ground temperature of the shallow permafrost on the plateau increased by approximately 1.155-1.575℃and the permafrost area decreased by approximately 0.34×10^(6)km^(2) from about 1.4×10^(6)km^(2) to 1.06×10^(6)km^(2) in the past decades.As indicated by simulated calculation results,the thickness of the NGH-bearing permafrost on the Qinghai-Tibet Plateau has decreased by 29-39 m in the past 50 years,with the equivalent of(1.69-2.27)×10^(10)-(1.12-1.51)×10^(12)m^(3) of methane(CH_(4))being released due to NGHs dissociation.It is predicted that the thickness of the NGH-bearing permafrost will decrease by 23 m and 27 m,and dissociated and released NGHs will be the equivalent of(1.34-88.8)×10^(10)m^(3) and(1.57-104)×10^(10)m^(3)of CH_(4),respectively by 2030 and 2050.Considering the positive feedback mechanism of NGHs on global warming and the fact that CH_(4) has a higher greenhouse effect than carbon dioxide,the NGHs in the permafrost on the Qinghai-Tibet Plateau will emit more CH_(4) into the atmosphere,which is an important trend of NGHs under the background of global warming.Therefore,the NGHs are destructive as a time bomb and may lead to a waste of efforts that mankind has made in carbon emission reduction and carbon neutrality.Accordingly,this study suggests that human beings should make more efforts to conduct the exploration and exploitation of the NGHs in the permafrost of the Qinghai-Tibet Plateau,accelerate research on the techniques and equipment for NGHs extraction,storage,and transportation,and exploit the permafrost-associated NGHs while thawing them.The purpose is to reduce carbon emissions into the atmosphere and mitigate the atmospheric greenhouse effect,thus contributing to the global goal of peak carbon dioxide emissions and carbon neutrality.

Energy Outlook in East Africa Region and the Carbon Emissions for Conventional En-ergy Projection (Part I)

In this investigation, we focus on the current energy sources and future projects situation in East Africa up to 2040. Electricity generation potential of energy mix and electrical capacity will be analyzed. For both electricity generation and electrical capacity, the data source shows that some forms of energies such bio-energy, solar PV, etc. will contribute less as well as with insignificant contribution of nuclear energy. Whereas hydro is dominating comparing with gas, oil, coal, solar PV, bio-energy and other renewables energies. From 2000 up to 2012, hydro and oil were only the one source of electricity generation. Starting from 2020, other forms of energies will appear and continue to increase at different rate. The international trade of electricity in this region will appear in 2020 and continue to increase as predicted by the data. Up to 2040, hydro will play a big role in electricity generation with other renewable energy sources, such as coal, oil, Gas, bio- energy and solar PV that will continue to increase at different rate. The share of solar PV in energy generation will slowly increase compared to other sources. The capacity of hydro and renewable energy sources will be high compared with other sources of energy such as bioenergy, coal, oil, PV solar, and gas. The results show also that bio-energy will increase slowly in electricity generation in comparison with other source of energies. The present report shows that oil will continue to emit a lot carbon dioxide compared to gas and coal. The emission of CO2 from total final consumption (TFC) of oil will continue to be high in comparing with CO2 emission from power generation (PG) of oil. But the emission of carbon dioxide from power generation of coal from 2025 until 2040 will be high compared with emission of CO2 generated from FTC of coal. In this period, the emission from TFC for gas will remain insignificant. The total final consumption emission of oil in general will dominate other emissions from both coal and gas. Due to this high emission of CO2, new technologies should be introduced in order to reduce gas pollution from TFC.

Analyzing the Share Composition of C02 Emissions in Asian Countries

This paper is concerned with the fossil fuel composition of carbon emissions in 10 selected Asian countries. It assesses how economic development may affect this composition through various channels. This paper contributes to the debate on the EKC （environmental Kuznets curve） puzzle, which hypothesizes an inverted U-shaped relationship between per capita income and pollution. The paper examines the EKC hypothesis in an empirical analysis of channels that may allow for this effect. In particular, a specific subset of this general paradigm is investigated using a fractional multinomial logit model to assess how indicators associated with economic development and energy prices affect carbon emissions from coal relative to those of natural gas and oil.

Does Foreign Direct Investment Affect S0_(2) Emissions in the Yangtze River Delta?A Spatial Econometric Analysis

As the major source of air pollution,sulfur dioxide(S0_(2))emissions have become the focus of global attention.However,existing studies rarely consider spatial effects when discussing the relationship between foreign direct investment(FDI)and S0_(2) emissions.This study took the Yangtze River Delta as the research area and used the spatial panel data of 26 cities in this region for 2004-2017.The study investigated the spatial agglomeration effects and dynamics at work in FDI and S0_(2) emissions by using global and local measures of spatial autocorrelation.Then,based on regression analysis using a results of traditional ordinary least squares(OLS)model and a spatial econometric model,the spatial Durbin model(SDM)with spatial-time effects was adopted to quantify the impact of FDI on S0_(2) emissions,so as to avoid the regression results bias caused by ignoring the spatial effects.The results revealed a significant spatial autocorrelation between FDI and S0_(2) emissions,both of which displayed obvious path dependence characteristics in their geographical distribution.A series of agglomeration regions were observed on the spatial scale.The estimation results of the SDM showed that FDI inflow promoted S0_(2) emissions,which supports the pollution haven hypothesis.The findings of this study are significant in the prevention and control of air pollution in the Yangtze River Delta.

A Review of the Life Cycle Analysis for Plastic Waste Pyrolysis

Pyrolysis is a rapidly expanding chemical-based recyclable method that complements physical recycling. It avoids improper disposal of post-consumer polymers and mitigates the ecological problems linked to the production of new plastic. Nevertheless, while there is a consensus that pyrolysis might be a crucial technology in the years to come, more discussions are needed to address the challenges related to scaling up, the long-term sustainability of the process, and additional variables essential to the advancement of the green economy. Herein, it emphasizes knowledge gaps and methodological issues in current Life Cycle Assessment (LCA), underlining the need for standardized techniques and updated data to support robust decision-making for adopting pyrolysis technologies in waste management strategies. For this purpose, this study reviews the LCAs of pyrolytic processes, encompassing the complete life cycle, from feedstock collection to end-product distribution, including elements such as energy consumption, greenhouse gas emissions, and waste creation. Hence, we evaluate diverse pyrolysis processes, including slow, rapid, and catalytic pyrolysis, emphasizing their distinct efficiency and environmental footprints. Furthermore, we evaluate the impact of feedstock composition, process parameters, and scale of operation on the overall sustainability of pyrolysis-based plastic waste treatment by integrating results from current literature and identifying essential research needs. Therefore, this paper argues that existing LCA studies need more coherence and accuracy. It follows a thorough evaluation of previous research and suggests new insights into methodologies and restrictions.