20 results on '"Na, Hongming"'
Search Results
2. Revealing cradle-to-gate CO2 emissions for steel product producing by different technological pathways based on material flow analysis
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Na, Hongming, Qiu, Ziyang, Sun, Jingchao, Yuan, Yuxing, Zhang, Lei, and Du, Tao
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- 2024
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3. Spatial and temporal dynamics of air-pollutant emission inventory of steel industry in China: A bottom-up approach
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Gao, Chengkang, Gao, Wengang, Song, Kaihui, Na, Hongming, Tian, Fan, and Zhang, Shuaibing
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- 2019
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4. Using forest area for carbon footprint analysis of typical steel enterprises in China
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Qi, Zhaoqian, Gao, Chengkang, Na, Hongming, and Ye, Zhou
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- 2018
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5. Status, challenges, and prospects of energy efficiency improvement methods in steel production: A multi-perspective review.
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Yuan, Yuxing, Na, Hongming, Chen, Chuang, Qiu, Ziyang, Sun, Jingchao, Zhang, Lei, Du, Tao, and Yang, Yuhang
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PRODUCTION methods , *ENERGY conservation , *STEEL manufacture , *MANUFACTURING processes , *STEEL industry , *ENERGY consumption , *RESIDENTIAL energy conservation - Abstract
Improving energy efficiency has been widely recognized as a direct, efficient, and cost-effective approach to advancing energy conservation, reducing emissions, and achieving sustainable development. While there are numerous and effective methods to enhance energy efficiency in a typical steel manufacturing system, they are relatively scattered and independent, lacking a systematic review for multi-level, comprehensive and scientific evaluation and improvement of energy efficiency within the steel industry. To fill this gap, this work initially presents an overview of the component units and energy networks within steel production system. Subsequently, a comprehensive review and analysis are conducted from multiple perspectives, such as energy evaluation, diagnosis, benchmarking analysis, optimization, and energy-saving measures. Each part meticulously selects the literature through content evaluation analysis to discuss methods, technologies, and models for improving energy efficiency, along with potential challenges that need to be overcome for future advancements. Furthermore, the paper examines the diverse challenges encountered by steel manufacturing in realizing energy efficiency improvements and exploring energy-saving potential. It also underscores the corresponding future developmental direction, including the construction of multi-level evaluation systems, implementation of intelligent energy efficiency improvement methods and technologies, and adoption of intelligent energy systems crucial for intelligent analysis and manufacturing in steel sector. • Energy efficiency improvement methods within the steel production sector are comprehensively reviewed. • Multi-level energy efficiency evaluation methods for the steel production are summarized. • Advances in energy efficiency diagnosis, benchmarking analysis, optimization and energy-saving technologies are summarized. • Challenges and prospects for energy efficiency improvement in steel sector are discussed. [ABSTRACT FROM AUTHOR]
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- 2024
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6. Copper nanoparticles encapsulated in zeolite 13X for highly selective hydrogenation of CO2 to methanol.
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Li, Yingnan, Du, Tao, Chen, Chuang, Jia, He, Sun, Jingchao, Fang, Xin, Wang, Yisong, and Na, Hongming
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ZEOLITES ,HYDROGENATION ,COPPER ,METHANOL ,CARBON dioxide ,METHANOL as fuel - Abstract
High dispersion of active metal is always approved for better catalytic performance in CO 2 hydrogenation to methanol. Herein, a strategy was proposed to encapsulate copper nanoparticles in supercages of zeolite 13X, and hence the growth of copper nanoparticles can be controlled. In the present work, catalysts were prepared using ion-exchange and hydrogen reduction at a tiny positive pressure. The results show that as-synthesized catalyst consists of metallic copper and FAU-type zeolite. Excessive amount of copper will destroy zeolite frameworks, and the amount of 5.9 at% is appropriate for considerable BET surface area and ideal copper dispersion. Meanwhile, copper nanoparticles may grow outside from zeolite at high reduction temperatures (≥220 °C), resulting in serious surface area decline and metallic copper agglomeration. Afterwards catalytic tests reveal good stability of the optimal CX-220 catalyst in continuous reactions. The CX-220 achieves remarkably high methanol selectivity of ≥ 95% within wide ranges of reaction temperatures and reaction pressures. Further analyses reveal that the encapsulation of copper nanoparticles reduces micropores and enriches mesopores in zeolite. The apparent activation energy for methanol synthesis over CX-220 catalyst has been lowered to a very low level because of the unique microstructure, and thus the methanol synthesis reaction is dominant in CO 2 hydrogenation for dramatic methanol selectivity. Therefore, this work gives important insights and applicable routes for catalysts analyses of CO 2 hydrogenation to methanol. [Display omitted] • Cu nanoparticles are successfully encapsulated in zeolite 13X with the proposed method. • Proper Cu content and reduction temperature are crucial for favorable microstructures. • Prepared samples achieve remarkably high methanol selectivity at studied reaction conditions. [ABSTRACT FROM AUTHOR]
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- 2024
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7. Integrated optimization for utilizing iron and steel industry's waste heat with urban heating based on exergy analysis.
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Zhang, Lei, Na, Hongming, Yuan, Yuxing, Sun, Jingchao, Yang, Yuhang, Qiu, Ziyang, Che, ZiChang, and Du, Tao
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WASTE heat , *EXERGY , *IRON industry , *THERMODYNAMIC laws , *STEEL industry , *WASTE recycling , *HEAT recovery - Abstract
[Display omitted] • Exergy loss of enterprise is optimized by building mathematical programming model. • Influences of 9 key factors on system's total exergy loss and cost are discussed. • Recovery and utilization of waste heat are optimized by detailed technical models. • Waste heat potential and heating capacity of enterprise are evaluated. • Interface loss between upstream & downstream processes is quantified by exergy. A substantial quantity of waste heat resources generated in iron and steel manufacturing process (ISMP) can fulfill certain demand for urban heating. However, the waste heat utilization level of different iron and steel enterprises varies a lot and few studies have combined the upstream enterprise's production with downstream waste heat utilization for discussion. By establishing an optimization model based on material balance, thermodynamic laws and reaction mechanism of the ISMP, this study firstly obtain the minimum exergy loss and the corresponding production cost & exergy efficiency. The total exergy loss of ISMP is reduced from 8413.19 MJ/t-MS to 7669.27 MJ/t-MS. The exergy efficiency of the whole process is increased from 63.75 % to 65.46 % and the total waste heat potential reaches 1471.25 MJ/t-MS. It is found that coke ratio, air leakage rate, scrap steel ratio, etc. have great impact on exergy loss of ISMP. Then, the optimization and evaluation of the waste heat utilization are carried out by establishing models with taking urban heating into consideration. The available external heat supply is 813.15 to 853.55 MJ/t-MS and the enterprise's heating load can reach 229.23–251.47 MW, which allow to supply heat for an area of 5.46–5.93 million m2. Finally, the problem of waste heat instability in the heating process is briefly discussed and some solution strategies are proposed to overcome this defect. [ABSTRACT FROM AUTHOR]
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- 2023
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8. Multi-objective optimization and analysis of material and energy flows in a typical steel plant.
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Yuan, Yuxing, Na, Hongming, Du, Tao, Qiu, Ziyang, Sun, Jingchao, Yan, Tianyi, and Che, Zichang
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MATERIALS analysis , *STEEL mills , *ENERGY consumption , *MANUFACTURING processes , *IRON , *CHEMICAL plants , *POWER plants - Abstract
The integrated optimization and analysis of material and energy flows are effective ways to reduce energy consumption and costs in the iron and steel sector. There is still a lack of research on the multi-objective optimization of the integrated steel production process and the auxiliary energy process. To fill this gap, this paper presented a single- and multi-objective optimization model for material and energy scheduling and utilization of the steelworks. This model considered physical and chemical conversion mechanisms in the production process, as well as operating characteristics and production-consumption relations of equipment in the gas-steam-electricity network. The objective function was constructed using comprehensive energy consumption (CEC) and economic cost (EC), and fuzzy sets were used to find a compromise solution and the trade-off operation strategies between the two goals. The CEC and EC effectively dropped by 5.09% and 7.29%, respectively, in comparison to the actual enterprise value, through the optimization of the material ratio, product structure, energy utilization, and other parameters of the steelworks. Additionally, a quantitative analysis of the effects of variables such as the ratio of pellets, the ratio of scrap, the hot charging temperature of the slab, and the utilization of surplus gases was conducted. • A single- and multi-objective optimization model for material and energy scheduling and utilization is proposed. • The compromise solution of energy consumption and economic multi-objective optimization is found. • Influence of material and energy flows on variation in multi-objective is discussed. • Highly efficient and cost-effective modes of using surplus gases are explored. [ABSTRACT FROM AUTHOR]
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- 2023
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9. Optimization of energy efficiency, energy consumption and CO2 emission in typical iron and steel manufacturing process.
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Na, Hongming, Sun, Jingchao, Qiu, Ziyang, Yuan, Yuxing, and Du, Tao
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STEEL manufacture , *CARBON emissions , *IRON , *ENERGY consumption , *BLAST furnaces , *MANUFACTURING processes , *STEEL mills - Abstract
Improving energy efficiency of the iron and steel manufacturing process (ISMP) plays a vital role in saving energy and reducing CO 2 emissions. However, there is currently a lack of research on assessment method and improvement rules of energy efficiency of the ISMP. In addition, the impact of energy efficiency on CO 2 emissions and energy consumption is rarely mentioned in previous studies. To fill this gap, this study establishes an assessment and optimization model of energy efficiency, energy consumption and CO 2 emissions in the ISMP. Taking material parameters, process parameters and reaction conditions as constraints, this study optimizes a practical ISMP with maximizing energy efficiency as the optimization goal, and further analyze energy consumption and CO 2 emissions of typical ISMP. After optimizing, energy efficiency of the ISMP is increased from 64.00% to 68.20%, energy consumption of the ISMP is reduced from 15.76 GJ/t-steel to 12.31 GJ/t-s, and the CO 2 emission of the ISMP is reduced from 1215.2 kg/t-steel to 815.3 kg/t-s. It is found that injected coal ratio of blast furnace, charge structure of blast furnace, iron-steel interface and casting-rolling interface have a greater impact on energy efficiency, energy consumption and CO 2 emission of the ISMP. • The optimization model of energy efficiency of the iron and steel making process is established. • The optimal energy efficiency of a typical steel plant is given. • Energy efficiency, energy consumption and CO 2 emissions are jointly analyzed. • The influencing factors of energy efficiency, energy consumption and CO 2 emission are discussed. • The iron-steel interface and casting-rolling interface are considered. [ABSTRACT FROM AUTHOR]
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- 2022
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10. Cost-benefit assessment of manufacturing system using comprehensive value flow analysis.
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Sun, Jingchao, Na, Hongming, Yan, Tianyi, Che, Zichang, Qiu, Ziyang, Yuan, Yuxing, Li, Yingnan, Du, Tao, Song, Yanli, and Fang, Xin
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MANUFACTURING processes , *CAPITALISM , *LEAN management , *ECONOMIC indicators , *IRON , *GLOBAL production networks , *DEEP drawing (Metalwork) - Abstract
• A novel assessment method is proposed to increase benefits of manufacturing systems. • Networks of material, energy, environment and economic are thoroughly considered. • The comprehensive value flow is presented considering the exergy of energy. • Feasible suggestions are therefore proposed to improve the performance in energy and economic. • It is confirmed efficient in following case study with dramatic improved comprehensive benefits. The comprehensive assessment of the performance of production system is a crucial activity for the implementation of sustainable production practices for the manufacturing industry. The existing relevant assessment methods are not comprehensive enough, especially in terms of material, energy, environment and economics. They lack specific economic performance indicators based on industrial systematic analysis, and couldn't give a clear explanation for the comprehensive value flow in the production process. This paper proposes a novel assessment method, called Comprehensive Value Flow Analysis, which aims to describe and classify activities in the network of material, energy, environment and economics according to systematic energy saving and lean production theory. The drawing method of comprehensive value flow and a new cost-benefit indicator named advanced cost-profit ratio are proposed for identifying quantitatively the criticalities related to activities, processes, systems, technologies, etc. And significant suggestions for the improvement strategies implementation are given. A case study of a typical iron and steel enterprise has been evaluated using this method. Moreover, it successfully identifies the issues about energy structure, production structure and technologies application with a global perspective by explicating the comprehensive value flow and analyzing the relevant indicators, and then offering some valuable suggestions for sustainable development. The analysis highlighted that every enterprise has its own marginal benefits according to the production status and market economy. In summary, it is favorable to make real and effective decisions on improvement for the comprehensive benefits of enterprises. [ABSTRACT FROM AUTHOR]
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- 2022
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11. A comprehensive assessment on material, exergy and emission networks for the integrated iron and steel industry.
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Sun, Jingchao, Na, Hongming, Yan, Tianyi, Qiu, Ziyang, Yuan, Yuxing, He, Jianfei, Li, Yingnan, Wang, Yisong, and Du, Tao
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IRON industry , *STEEL industry , *EXERGY , *ENERGY management , *CARBON emissions - Abstract
Intensive energy consumption and high pollutant emission have always been the obstacles for achieving the sustainable development of the iron and steel (I&S) industry. The complex material flows, energy flows and emission flow of I&S industry require better assessment to implement comprehensive governance and impact analysis. The 48-month data of a typical I&S enterprise is used for evaluating intensities and analyzing influencing factors from the perspective of material, exergy and emission networks. The results show that the exergy intensity and carbon emission intensity of the whole site including main processes and auxiliary processes are 23.804 GJ/t-CS and 1642.7 kg/t-CS, respectively. In particular, auxiliary process plays a critical role, whose exergy loss accounts for about 28.85% of the total. The terms of energy structure, technology capacity, product structure and environmental conditions are considered to analyze on the influencing factors of the case, and then providing relevant suggestions. On the whole, integration assessment of material-exergy-emission networks of I&S industry is necessary and helpful to find their changes and migration, and to further implement energy management and emission reduction. • Material-exergy-emission network is analyzed for the whole iron & steel enterprise. • The data of main and auxiliary processes with time granularity are analyzed. • The intensities of energy, exergy and emission of various products are presented. • The influencing factors for the material-exergy-emission network are discussed. [ABSTRACT FROM AUTHOR]
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- 2021
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12. A novel evaluation method for energy efficiency of process industry — A case study of typical iron and steel manufacturing process.
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Na, Hongming, Sun, Jingchao, Qiu, Ziyang, He, Jianfei, Yuan, Yuxing, Yan, Tianyi, and Du, Tao
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STEEL manufacture , *ENERGY consumption , *MANUFACTURING processes , *BASIC oxygen furnaces , *ENERGY conservation , *ROLLING (Metalwork) , *HEAT recovery - Abstract
Energy efficiency is an extremely important indicator for exploring energy conservation and consumption reduction. The traditional energy efficiency assessment methods for process industry lack an in-depth thinking on energy utilization of the whole system. Based on the proposed required energy, this paper established an energy efficiency assessment method for process industry. By establishing material and energy flow networks, energy efficiency of typical iron and steel manufacturing process (ISMP) is analyzed and its influencing factors are discussed. The results found that the required energy of coking, sintering, pelletizing, blast furnace iron-making, basic oxygen furnace steel-making and steel rolling are 2626.2 MJ/t-coke, 1122.9 MJ/t-sinter, 992.3 MJ/t-pellet, 9781.5 MJ/t-hot metal, 393.95 MJ/t-molten steel and 445.3 MJ/t-steel products, respectively. The energy efficiency of typical ISMP is 66.9%. The energy efficiency of the ISMP can be effectively improved by adjusting the steel ratio, recovering waste heat and residual energy, and developing interface technologies. • Energy efficiency assessment method of process industry is proposed and established. • The material and energy flow networks of iron and steel manufacturing process are established. • The required energy of iron and steel manufacturing process is analyzed and given. • Energy efficiency of typical iron and steel manufacturing process is evaluated and given. • The influencing factor of energy efficiency is discussed. [ABSTRACT FROM AUTHOR]
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- 2021
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13. A novel method for intelligent heating: On-demand optimized regulation of hydraulic balance for secondary networks.
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Che, Zichang, Sun, Jingchao, Na, Hongming, Yuan, Yuxing, Qiu, Ziyang, and Du, Tao
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CARBON offsetting , *ENERGY conservation , *HYDRAULIC models , *HEAT losses , *ENERGY consumption , *VALVES , *HEATING - Abstract
In the context of carbon neutrality, energy conservation and carbon reduction in the heating industry have become the focus of attention. However, severe heat loss is currently occurring in the secondary heating system due to hydraulic imbalance, which is unable to supply heat according to users' needs. In view of this, a thermodynamic-hydraulic model of users' demand for heat and flow rate for the heating system is established. Then, a novel method to regulate hydraulic imbalance is proposed, with the dynamic heat demand satisfied by regulating the valve opening based on NSGA-II. The optimization results show that the comprehensive hydraulic imbalance coefficient has been reduced from 23.08 to less than 0.019, which means that almost 100% of users can get heat supplies corresponding to their needs, while the energy consumption is reduced by about 30%. Additionally, when there are 1000 population and iteration steps, good convergence and high speed are presented using this method. In summary, an on-demand optimized model of hydraulic balance for the secondary heating network is put forward, which provides powerful engineering support and guidance for intelligent heating construction. • This paper presents a method to regulate the hydraulic balance of network using NSGA-II according to the heat demand. • This paper combines the demand flow regulation of users with the resistance analysis of the heating network. • The hydraulic balance can be implemented greatly by using the hydraulic imbalance coefficient as the optimization goal. • The number of iteration steps in the algorithm has an effect on the optimization results. [ABSTRACT FROM AUTHOR]
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- 2023
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14. Impact of hydrogen metallurgy on the current iron and steel industry: A comprehensive material-exergy-emission flow analysis.
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Qiu, Ziyang, Sun, Jingchao, Du, Tao, Na, Hongming, Zhang, Lei, Yuan, Yuxing, and Wang, Yisong
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IRON metallurgy , *STEEL industry , *IRON industry , *ARC furnaces , *BASIC oxygen furnaces , *CARBON emissions - Abstract
The development of hydrogen metallurgy holds enormous significance in facilitating the low-carbon and environmentally sustainable transition of iron and steel industries. However, there is a lack of research on the impact of implementing hydrogen metallurgy on the downstream process and even the whole process. To fill this research gap, a model that considers specific internal reactions of steelmaking process was developed utilizing the bottom-up approach. Subsequently, by integrating the hydrogen metallurgy process with the traditional long process and short process, the energy intensity, exergy intensity and carbon emission intensity were quantitatively analyzed from multiple viewpoints. The results of the basic oxygen furnace (BOF) and electric arc furnace (EAF) exhibit a degree of similarity, with an increase in directly reduced iron (DRI) addition, resulting in an insufficient heat and an increase in process energy consumption, exergy loss, and carbon emissions. But there are also some subtle differences, such as oxygen consumption. Following the integration of hydrogen metallurgy, the energy intensity and exergy intensity of the BF-BOF process increase 11.984 kgce/t-CS and 3.083 × 102 MJ/t-CS, respectively. However, the carbon emission intensity decreased by 46.514 kg/t-CS. The integrated Chinese-style short process has the lowest carbon emission intensity of 879.664 kg/t-CS at 40% DRI and 60% scrap. Nevertheless, the energy intensity and exergy intensity have increased by 27.383 kgce/t-CS and 42.012 × 102 MJ/t-CS respectively compared to their initial values. It is noteworthy that the process of hydrogen production plays a significant role in mitigating the exergy intensity and carbon emission intensity. [Display omitted] • The white box model based on material-energy-exergy flow of furnace are created. • The material–energy–emission nexus model of integration processes is proposed. • Energy intensity, exergy intensity and carbon emission intensity are introduced as indicators. • Impacts of direct reduced iron addition on variation in indicators are discussed. • Hydrogen production process has an important impact on the indicators. [ABSTRACT FROM AUTHOR]
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- 2024
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15. An evaluation of greenhouse gas emission efficiency in China's industry based on SFA.
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Sun, Jingchao, Du, Tao, Sun, Wenqiang, Na, Hongming, He, Jianfei, Qiu, Ziyang, Yuan, Yuxing, and Li, Yingnan
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As one of the largest countries with sound industrial systems in the world, China is a major emitter of greenhouse gases. In order to achieve sustainable development, the analysis of greenhouse gas emissions from industry is of great significance. This research evaluates the greenhouse gas emission efficiency (GHG efficiency) at industry level in 26 sectors of China and analyzes the impacts of its determinants using stochastic frontier approach. Furthermore, the correlations for GHG efficiency with its determinants and other proxies are estimated by Kendall's rank analysis. Industry level data from Chinese processing and manufacturing industries spanning over the period 2000–2016 are used for this analysis. Results show that there has little potential to improve GHG efficiency, then technology progress is necessary. The GHG efficiency performance responds both to changes in the proportion of net electricity use and the ratio of electricity price to coal price; meanwhile the technology capacity also has a positive impact. Besides, three main proxies of GHG intensity, energy efficiency and energy intensity have their own significance respectively, but could not represent GHG efficiency. Unlabelled Image • China's GHG efficiency at industry level is assessed by stochastic frontier analysis. • At night, net electricity is better than small-scale on-site coal-fired power plant. • Technology advance is better to improve efficiency and mitigate GHG emissions. • Energy efficiency and GHG efficiency are dependent but loosely related indexes. [ABSTRACT FROM AUTHOR]
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- 2019
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16. Decarbonization potential collaborated with source industries for China's iron and steel industry towards carbon neutrality.
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Sun, Jingchao, Qiu, Ziyang, Yuan, Yuxing, Che, Zichang, Zhang, Lei, Du, Tao, Na, Hongming, and Li, Yingnan
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IRON industry , *CARBON dioxide mitigation , *CARBON emissions , *STEEL industry , *CARBON pricing , *CARBON offsetting , *GREENHOUSE gas mitigation - Abstract
Towards the target of carbon neutrality, the need for deep decarbonization in iron and steel industry is increasingly recognized. Existing studies rarely mention the effects of collaboration with its source industries for carbon emission reduction in ISI. Furthermore, the fundamental laws of CO 2 emission reduction capacity with cost change of source substitutions for various steel production routes under market economics are unclear. To avoid the blind substitution of clean sources for meeting the urgent requirements for decarbonization in China's steel industry, which may result in increased carbon emissions and uneconomical carbon reduction from a lifecycle perspective. This paper integrates the production and utilization processes of source resources into the steel production process, establishes coupling models of carbon and value flows for four main types of steel production routes, and aims to quantitatively analyze the specific CO 2 emission reduction potential and costs. Three economic market development scenarios from 2021 to 2060 are set, and the marginal carbon prices of various source substitutions are determined. Subsequently, decarbonization pathways with the goal of minimizing production costs are developed. Finally. The future resource demand and the carbon emission reduction contributions of source industries collaborated are predicted. The results show that (1) about 81.7–89.9 % of CO 2 emissions could be reduced in the scenarios; (2) the demands of electric power and hydrogen energy will reach 54.48–511.90 BkWh and 7.47–10.31 Gt in 2060, respectively; and (3) collaboration with source industries could make 18.3–18.3% of CO 2 emission reduction contributions. All in all, this study could provide scientific support for the low-carbon transformation of China's steel industry. • Carbon and value flows of BF-BOF, Scrap-EAF, DRI-EAF, MOE-EAF routes are analyzed. • CO 2 emission reduction potential with marginal carbon price is determined. • Decarbonization paths during 2021–2060 for China's steel industry are developed. • Quantify the contribution of collaborative carbon reduction with source industries. [ABSTRACT FROM AUTHOR]
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- 2023
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17. A multi-parameters evaluation on exergy for hydrogen metallurgy.
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Qiu, Ziyang, Du, Tao, Yue, Qiang, Na, Hongming, Sun, Jingchao, Yuan, Yuxing, Che, Zichang, Wang, Yisong, and Li, Yingnan
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EXERGY , *METALLURGY , *SECOND law of thermodynamics , *GAS furnaces , *WASTE recycling , *BACTERIAL leaching - Abstract
The traditional iron and steel industry (ISI) began to implement technological innovations aimed at lowering carbon footprint and emissions, resulting in hydrogen metallurgy gradually becoming a new trend of green development in ISI. However, there is a lack of comprehensive and in-depth analysis of energy-exergy based on the second law of thermodynamics in the current research of hydrogen metallurgy. To address these issues, a numerical calculation model of hydrogen metallurgy based on material-energy-exergy is established. Two novel evaluation indexes are introduced to better evaluate the impact of various parameters on hydrogen metallurgy. It was found that the exergy intensity is mainly affected by the amount of reducing gas, and increasing the preheating temperature of the ore cannot always reduce the exergy intensity due to the influence of element conservation. And when the ore preheating temperature is higher than 623 K, the exergy utilization efficiency decreases. After calculation, the lowest exergy intensity is 1.23 × 107 kJ/t-DRI when the H 2 content is 41.37% and the ore temperature is 773 K. Furthermore, a simple process is designed to recover a substantial volume of unreacted gas from the furnace top gas. Overall, this study can serve as a reference for actual hydrogen metallurgy production. [Display omitted] • A material-energy-exergy model based on the second law of thermodynamics is created. • In addition to the traditional evaluation indexes, two novel ones are also introduced. • Preheating ore temperature above 623 K reduces the exergy utilization efficiency. • Rising ore preheating temperature does not decrease exergy intensity continuously. • A simple waste energy recovery process is proposed. [ABSTRACT FROM AUTHOR]
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- 2023
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18. Comprehensive evaluation on energy-water saving effects in iron and steel industry.
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Gao, Chengkang, Gao, Wen'gang, Song, Kaihui, Na, Hongming, Tian, Fan, and Zhang, Shuaibing
- Abstract
Abstract The production of iron and steel is energy-intensive that motivated the emergence of various energy-saving technologies to reduce energy consumption. However, the effects of water-saving brought by these energy-saving technologies are rarely examined which can lead to misevaluation of their economic feasibility. In this regard, material flow analysis (MFA) was used in this study to establish the water-energy nexus and examine the potential of water-saving and energy-saving effects in the condition of applying various mixes of the 16 technologies (Ministry of Industry and Information Technology, 2015–2016) in iron and steel industry. Meanwhile, this study classified the selected 16 energy-saving technologies into three groups: direct water-saving technology, indirect water-saving technology, and water consumption technology. The low-temperature steel rolling technology is the only water-consuming energy-saving technology in this study; its indirect specific water computation reaches 0.06 m3/t. The remaining 15 energy-saving technologies have the potential of saving water indirectly, with averaged indirect specific water-saving amounting to 0.28 m3/t. This study also built an evaluation scheme of cost-benefit analysis for energy-saving technologies. With consideration of benefits brought by water saving, eleven technologies have the potential to achieve economic feasibility compared to nine in which mere energy-saving effects being considered. The results show that if the studied 16 technologies are implemented simultaneously, the comprehensive specific energy consumption will be reduced by 4.28 MJ, and the specific fresh water consumption will be reduced by 0.68 m3. Meanwhile, this research found that the cost of most energy-saving technologies will be decreased by an average of 5.52 CNY/GJ, despite the cost of low-temperature steel rolling technology increased by 0.68 CNY/GJ. This study evaluated the cost-effectiveness of energy-saving technologies taking the benefits of water conservation into consideration. It could provide references for decision-makers to develop commercialization strategies on energy saving technologies in the steel industry. [ABSTRACT FROM AUTHOR]
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- 2019
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19. Conjoint analysis of nitrogen, phosphorus and sulfur metabolism: A case study of Liaoning Province, China.
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Gao, Chengkang, Zhang, Shuaibing, Song, Kaihui, Na, Hongming, Tian, Fan, Zhang, Menghui, and Gao, Wengang
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CONJOINT analysis , *NITROGEN , *PHOSPHORUS , *SULFUR metabolism , *SOILS - Abstract
Highlights • A material metabolism model on the provincial scale was established based on Substance Flow Analysis. • A comprehensive analysis of elemental metabolism was presented to explain environmental problems. • Critical nodes in metabolism was identified by establishing metabolic topologies. Abstract The three types of elements nitrogen (N), phosphorus (P) and Sulfur (S) are inextricably linked from the source to the destination throughout the system. To analyze the environmental load caused by the three elements, this study established a material metabolism model to quantify the relationships among metabolic processes on the provincial scale and examined their environmental implications based on Substance Flow Analysis (SFA). The results show that the metabolic fluxes of nitrogen, phosphorus and sulfur in the socioeconomic system of Liaoning Province in 2016 were 5.339 million tons, 0.582 million tons and 3.084 million tons, respectively. The agricultural sector caused the greatest environmental pressures on water bodies, in which nitrogen and phosphorus accounted for 61.8% and 80.2% of the total water body load. For atmospheric load, the nitrogen and sulfur elements in the industrial sector caused the largest atmospheric load, accounting for 37.8% and 91.4% of the total atmospheric load, respectively. The main source of phosphorus soil load in Liaoning Province is the agricultural production, accounting for 85.3% of the total soil load caused by phosphorus. [ABSTRACT FROM AUTHOR]
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- 2018
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20. Comprehensive comparison of multiple renewable power generation methods: A combination analysis of life cycle assessment and ecological footprint.
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Gao, Chengkang, Zhu, Sulong, An, Nan, Na, Hongming, You, Huan, and Gao, Chengbo
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ECOLOGICAL impact , *RENEWABLE energy sources , *ECOLOGICAL assessment , *MULTIPLE comparisons (Statistics) , *ENERGY development , *PHOTOVOLTAIC power generation - Abstract
As the goal of carbon neutrality has been proposed consecutively, renewable energy sources such as wind, solar, and bioenergy are gaining close attention in national strategic and sustainable development plans. Along with the development of renewable energy generation technologies, it is necessary to assess the environmental burden of renewable energy generation. This study analyzed the economic and environmental benefits of wind power, solar power, and biomass power generation methods over their life cycle. This paper comprehensively assessed and compared their environmental impacts based on a life cycle assessment (LCA) framework combined with ecological footprint analysis for the three renewable energy generation in China, and compared the results with those of thermal power generation to make strategic suggestions for the renewable energy power generation industry. The results show that: (1) wind power consumed the least energy, only 6.80 kJ/kW·h, and had the lowest emissions of CO 2 , SO 2 , NOx and CO and environmental impact potential. (2) Based on the ecological footprint analysis on the provincial level, only Anhui, Shandong and Jiangsu provinces showed ecological deficits, while the other provinces were in ecological surplus, mostly above 50% of their ecological areas. (3) Compared to thermal power generation, which consumed 1170.911 kJ/kW·h, wind power was the only one of the three renewable energy achieved a reduction in energy consumption. Wind power is currently the most efficient way of generating renewable energy. [Display omitted] • The environmental and economic benefits of wind power, solar photovoltaic power, and biomass power generation were assessed. • Life cycle assessment and ecological footprint were used as analytical methods. • Wind power generation is preferred to solar photovoltaic and biomass power generation. • Recommendations for the future development of the renewable energy generation industry are presented. [ABSTRACT FROM AUTHOR]
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- 2021
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