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61.
根据目前市场形势以及宝钢股份炼钢厂的生产特点,总结了2016年以来炼钢厂通过推进成本管理模式创新、能源管理模式转变、少渣冶炼工艺推进、直接出钢工艺、连浇炉数提升、加强成本对标等措施,提高了精细化成本管理水平,各方面消耗均有长足进步,实现了低成本规模化生产,同时为同行业如何在市场严峻的形势下取得好的效果提供参考与借鉴。 相似文献
62.
《工程(英文)》2018,4(3):421-429
Goethite is a metals-rich residue that occurs during zinc production. The feasibility of metal recovery from goethite has been demonstrated, but is not economically viable on an industrial scale. Therefore, goethite is landfilled with considerable economic costs and environmental risks. The goal of this study is to evaluate the environmental performance of a new valorization strategy for goethite residues from zinc production, with the aims of: ① recovering the valuable zinc contained in the goethite and ② avoiding the landfilling of goethite by producing a clean byproduct. The presented goethite valorization strategy consists of a sequence of two processes: ① plasma fuming and ② inorganic polymerization of the fumed slag. Plasma fuming recovers the valuable metals by fuming the goethite. The metals-free fumed slag undergoes a process of inorganic polymerization to form inorganic polymers, that can be used as a novel building material, as an alternative to ordinary Portland cement (OPC)-based concrete. Life-cycle assessment (LCA) is used to compare the environmental performance of the inorganic polymer with the environmental performances of equivalent OPC-based concrete. The LCA results show the tradeoff between the environmental burdens of the fuming process and inorganic polymerization versus the environmental benefits of metal recovery, OPC concrete substitution, and the avoidance of goethite landfilling. The goethite-based inorganic polymers production shows better performances in several environmental impact categories, thanks to the avoided landfilling of goethite. However, in other environmental impact categories, such as global warming, the goethite valorization is strongly affected by the high-energy requirements of the plasma-fuming process, which represent the environmental hotspots of the proposed goethite recycling scheme. The key elements toward the sustainability of goethite valorization have been identified, and include the use of a clean electric mix, more effective control of the fumed gas emissions, and a reduced use of fumed slag through increased efficiency of the inorganic polymerization process. 相似文献
63.
In this study, we aimed to provide important information about the potential economic benefits and risks of nuclear electricity generation associated with existing and prevailing nuclear technologies and to examine the economic effects of nuclear fuel cycle strategies in Korea. An economic analysis model that evaluates the overall life‐cycle costs of nuclear energy systems coupled with multiple fuel cycle options was specially developed by using the levelized cost of electricity (LCOE) as the fundamental methodology. This model is capable of identifying a range of techno‐economic uncertainties underlying each individual nuclear energy system taking into account the state of the art in fuel cycle technologies. It can also quantify and incorporate the resulting impacts into a system‐wide LCOE distribution for each fuel cycle option based on Monte Carlo probabilistic simulation. We analyzed and discussed examples of the economic performance of 13 promising candidates for nuclear energy systems integrated with extensive fuel cycle technologies (including one direct disposal and 12 specific reprocessing and recycling fuel cycle options). We also conducted a sensitivity analysis to investigate the major sensitivity factors of the system component cost in each fuel cycle option and their impacts on individual economic performances. Furthermore, a closer look at the techno‐economic uncertainties of advanced fuel cycle technologies in a break‐even analysis offers evidence of the potential economic feasibility and cost‐reduction opportunities in the reprocessing and recycling options relative to the direct disposal of spent nuclear fuel. 相似文献
64.
Akhil Garg Liu Yun Su Shaosen Ankit Goyal Xiaodong Niu Liang Gao Yogesh Bhalerao Biranchi Panda 《国际能源研究杂志》2019,43(9):4390-4402
The present research proposes a combined framework that evaluates remaining capacity, material behavior, ions concentration of remaining metals, and current rate of chemical reactions of spent Li‐ion batteries accurately. Voltage, temperature, internal resistance, and capacity were studied during charging and discharging cycles. Genetic programming was applied on the obtained data to develop a model to predict remaining capacity. The results of experimental work and those estimated from model were found to be correlated, confirming the validation of model. Materials structure and electrochemical behavior of electrodes during cycles were studied by cyclic voltammetry, scanning electron microscopy, and energy dispersion spectrum. 相似文献
65.
Serap Ulusam Seçkiner Al Mothana Al Shareef 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2019,41(17):2157-2170
In chemical industries such as lube oil recycling units, stakeholders seek to continuously increase the productivity and profitability of the chemical processes to survive in the market. While scholars have investigated technological production options, recycling, and lube oil recycling flows, there is not enough study that evaluates the interplay between the production volume allocation and the recycled oil quality and quantity contingent upon the process temperature and pressure. The results based on a case study in the Kayalar Dorse production in Turkey show that by optimizing the chemical process mix, the volume of the lubricant oil can be increased by 20% at almost zero variable cost increase. 相似文献
66.
67.
A High‐Performance Recycling Solution for Polystyrene Achieved by the Synthesis of Renewable Poly(thioether) Networks Derived from d‐Limonene 下载免费PDF全文
68.
介绍了纺织工业印染污水分别经前处理污水处理工艺和染色、后整理污水处理工艺处理,实现了水资源的再利用. 相似文献
69.
Experiments were carried out in a system with BOF slags from industrial operations in order to optimize the conditions of recycling BOF slags produced in the steelmaking process. Reduction reactions of FeO and P2O5 proceeded steadily and the FeO reduction rate was almost identical to that of P2O5. The reduction reaction of FeO and P2O5 in BOF slag at the slag/gas interface is the rate‐controlling step. The reaction rates of FeO and P2O5 by dissolved carbon in molten iron are of first order with respect to their respective concentrations. The reduction reactions of FeO and P2O5 by dissolved carbon in iron are much closer to the equilibrium state compared with the reduction by solid carbon. It is necessary to control the portion of phosphorus vaporization during reduction treatment in order to obtain efficient operational conditions for BOF slag reduction. 相似文献
70.
含铁尘泥回收及利用技术现状及发展方向 总被引:1,自引:0,他引:1
在对含铁尘泥的来源、性质和分类进行界定的基础上,系统地介绍了国内外含铁尘泥处置、回收及利用技术现状,指出了含铁尘泥回收与利用的发展方向,可为钢铁工业含铁尘泥的综合利用提供参考。 相似文献