Clean production of Fe-based amorphous soft magnetic alloys via smelting reduction of high-phosphorus iron ore and apatite

Separated preparation of prealloys and amorphous alloys results in severe solidification-remelting and beneficial element removal-readdition contradictions,which markedly increase energy consumption and emissions.This study offered a novel strategy for the direct production of FePC amorphous soft magnetic alloys via smelting reduction of high-phosphorus iron ore(HPIO)and apatite.First,the thermodynamic conditions and equilibrium states of the carbothermal reduction reactions in HPIO were calculated,and the element content in reduced alloys was theoretically determined.The phase and structural evolutions,as well as element migration and enrichment behaviors during the smelting reduction of HPIO and Ca_(3)(PO_(4))_(2),were then experimentally verified.The addition of Ca_(3)(PO_(4))_(2)in HPIO contributes to the enrichment of the P element in reduced alloys and the subsequent development of Fe_(3)P and Fe_(2)P phases.The content of P and C elements in the range of 1.52 wt% -14.63 wt% and 0.62 wt% -2.47 wt%,respectively,can be well tailored by adding 0-50 g Ca_(3)(PO_(4))_(2)and controlling the C/O mole ratio of 0.8-1.1,which is highly consistent with the calculated results.These FePC alloys were then successfully formed into amorphous ribbons and rods.The energy consumption of the proposed strategy was estimated to be 2.00×10^(8) kJ/t,which is reduced by 30% when compared with the conventional production process.These results are critical for the comprehensive utilization of mineral resources and pave the way for the clean production of Fe-based amorphous soft magnetic alloys.

Clean Production and Ecological Industry:A Key to Eco-city Development

Eco-city development is a healthy process towards sustainable development, within the carrying capacity of local ecosystem through changing production mode, consumption behavior and decision instrument based on ecological economics and system engineering. The key to its planning is an ecological integration to make trade-off between economic wealth and environmental health, between material and spiritual civilization, between natural and human eco-cybernetics. Integration, demonstration, citizens’ participation and scientists’ and technician’s catalyzing are the key instruments for the implementation of the ecocity plan. "Clean production" and "ecological industry" are key elements in comprehensive development towards an eco-city. Beyond the technical and management questions, how to interlink production, consumption and reduction at the local and regional level, the spatial and urban dimension should be considered in order to perform an integrative urban eco-space.

CLEAN PRODUCTION AND SMELTING REDUCTION TECHNOLOGY

Clean Production is the best method for iron-steel making industry to eliminate pollution thoroughly. In order to achieve this object, smelting reduction technology should play the key role. Furthermore, process integration method can be used to solve the problem of residual gas utilization by integrating smelting reduction process with direct reduced iron unit, gasoline, methanol or dimethyl ether synthesis unit, etc. A new smelting reduction process has been proposed which can be constructed on the present plant site. Since this process can directly treat the lump coal and iron ore fines, it reduces st6ps necessary in traditional blast furnace process and Corex smelting reduction process.

Clean Production for Chrome Free Leather by Using a Novel Triazine Compound

Based on a novel triazine compound,the properties of tanned leather and commercial feasibility in pilot scale have been investigated.Then this novel approach tanning was compared with conventional chrome tanning:in the condition of less-salt pickling and chrome free,the physicochemical properties including thermal stability and mechanical strength were analyzed.Meanwhile,the surface roughness and fiber dispersion were evaluated as well.The results show that the thermal stability and mechanical strength of the triazine compound tanned leather are similar to conventional chrome tanned leather,the fiber bundle is well-dispersed and much evener than that of chrome treating.The optimized tanning approach has obvious reduction in environmental impact and leads an excellent biodegradability of tanning liquor.In industrial application,the cost of materials and water treatment are reduced effectively.The production of chrome free leather can encourage the sustainable development of leather industry and protects ecological environment in some extent.

The practice of clean production in the Ironmaking Plant of Tangshan Iron & Steel Co.,Ltd.

The Ironmaking Plant of Tangshan Iron & Steel Co.Ltd.takes clean production as its orientation. It decreases silicon to smelt through increasing the entering furnace sinter ratio,stabilizing coke quality by tackling key problems,increasing coal injection ratio,as well as keeping the blast furnace smooth running and so on.The energy consumption of sinter working procedure has been greatly reduced through optimizing the ore blender structure,enhancing the quality of fuel and flux,increasing the quicklime amount,reclaiming the remaining heat of the annulus cooling system and deepening the material layer to sinter.We have achieved the repetition economy and the secondly resource has been used synthetically with advanced producing technics.The environment around the plant has been greatly improved by preventing,monitoring and fathering the moving pollution root,at the same time,the economy and environment development in phase has been greatly accelerated.

Photothermal-photocatalytic thin-layer flow system for synergistic treatment of wastewater

The integration of the photocatalytic effect into solar steam is highly desirable for addressing freshwater shortages and water pollution.Here,a ternary film structure for the adsorption and photothermal and photocatalytic treatment of wastewater was designed by combining the technique of self-assembled carbon nano paper with a nitrogen composite titanium dioxide(N-TiO_(2))deposited on the surface of carbon nanotubes(CNT)using polyvinylidene fluoride(PVDF)as a substrate.The photogeneration of reactive oxygen species can be promoted by rapid oxygen diffusion at the three-phase interface,whereas the interfacial photothermal effect promotes subsequent free radical reactions for the degradation of rhodamine B(93%).The freshwater evaporation rate is 1.35 kg·m^(-2)·h^(-1)and the solar-to-water evaporation efficiency is 94%.Importantly,the N-TiO_(2)/CNT/PVDF(N-TCP)film not only effectively resists mechanical damage from the environment and maintains structural integrity,but can also be made into a large film for outdoor experiments in a large solar energy conversion device to collect fresh water from polluted water and degrade organic dyes in source water simultaneously,opening the way for applications in energy conversion and storage.

A New Cleaner Power Generation System Based on Self-Sustaining Supercritical Water Gasification of Coal

A new cleaner power generation system(IPGS) is proposed and investigated in this paper. Integrating combined cycle with supercritical water gasification of coal, the thermodynamic energy of the produced syngas is cascade utilized according to its temperature and pressure, both sensible and latent heat of the syngas can be recycled into the system, and thereby the net power efficiency can be about 6.4 percentage points higher than that of the traditional GE gasification based power plant(GEPP). The exergy analysis results show that the exergy efficiency of the proposed system reaches 52.45%, which is 13.94% higher than that of the GEPP, and the improvement in exergy efficiency of the proposed system mainly comes from the exergy destruction decline in the syngas energy recovery process, the condensation process and the syngas purification process. The syngas combustion process is the highest exergy destruction process with a value of 157.84 MW in the proposed system. Further performance improvement of the proposed system lies in the utilization process of syngas. Furthermore, system operation parameters have been examined on the coal mass fraction in the supercritical water gasifier(GF), the gasification temperature, and the gasification pressure. The parametric analysis shows that changes in coal concentration in the GF exert more influence on the exergy efficiency of the system compared with the other two parameters.

Environmental risks of shale gas exploitation and solutions for clean shale gas production in China

Shale gas is a relatively clean-burning fossil fuel,produced by hydraulic fracturing.This technology may be harmful to the environment;therefore,environmentally friendly methods to extract shale gas have attracted considerable attention from researchers.Unlike previous studies,this study is a comprehensive investigation that uses systematic analyses and detailed field data.The environmental challenges associated with shale gas extraction,as well as measures to mitigate environmental impacts from the source to end point are detailed,using data and experience from China’s shale gas production sites.Environmental concerns are among the biggest challenges in practice,mainly including seasonal water shortages,requisition of primary farmland,leakage of drilling fluid and infiltration of flowback fluid,oil-based drill cuttings getting buried underground,and induced seismicity.China’s shale gas companies have attempted to improve methods,as well as invent new materials and devices to implement cleaner processes for the sake of protecting the environment.Through more than 10-year summary,China’s clean production model for shale gas focuses on source pollution prevention,process control,and end treatment,which yield significant results in terms of resource as well as environmental protection,and can have practical implications for shale gas production in other countries,that can be duplicated elsewhere.

Mold flux entrainment mechanisms

This paper presents a comprehensive and critical review of mold flux entrainment mechanisms in continuous casting of steel.Entrainment introduces inclusions into the final product,and thus greatly hinders clean steel production.By understanding the mechanisms that cause entrainment,the operating conditions of casters can be tuned to reduce the number of defects.Nine different mechanisms have been proposed over the last three decades,including vortex formation around the submerged entry nozzle(SEN),argon bubble interactions with the slag layer,shear-layer instability at the slag-steel interface,excessive upward flow impingement upon the meniscus, top surface level fluctuations,meniscus freezing and hook formation,top surface 'balding',top surface standing wave instability,and slag crawling down the SEN.The previous work done for each of these mechanisms is presented,including both quantitative and qualitative descriptions of their behavior.

Green transformation of manufacturing industry for ecological protection in Jiangsu Province

Under the new normal economy, the manufacturing industry is developing rapidly as the focus of economic development in Jiangsu. Its rapid development has brought great opportunities to our society, but at the same time, great challenges has been brought to the natural environment. The resource consumption and environmental pollution problems have become increasingly prominent. In the face of this situation, we must try every means to reduce pollution and save energy. Therefore, the transition trend of manufacturing industry in the future is bound to take the green economy as the background. Thus, this paper analyzes the drawbacks of the manufacturing industry in Jiangsu province. And the status of traditional manufacturing enterprises and advantages of green manufacturing are analyzed. Then, the paper proposed to explore the practice of green manufacturing mode for the ecological protection, so as to achieve the industrial transformation and upgrading of manufacturing industry in Jiangsu province.

窄能隙吸光型共轭聚苯并二噻唑:大规模界面合成及其强太阳能光热蒸发和温差发电性能

为了实现低能耗太阳能蒸发和纯净水富集,开发先进的吸光型共轭聚合物是非常重要的.本研究通过界面化学大规模合成了共轭聚苯并二噻唑微球,其带隙窄至0.274 eV,太阳光吸收率高达94.0%.由聚苯并二噻唑微球与聚乙烯醇水凝胶可组装成Janus型蒸发器.当聚苯并二噻唑微球涂布量为5 mg cm^(-2)时,自支撑Janus型太阳能蒸发器的蒸发速率和能量效率分别达到2.96 kg m^(-2) h^(-1)和98.8%.Janus型蒸发器对模拟海水、污水和酸/碱性溶液具有强效脱盐和净化性能.装配了Janus型蒸发器的便携式太阳能净水装置可将真实海水淡化至远高于饮用水标准,并将真实污水的化学需氧量净化至极低水平.Janus型蒸发器还可与温差发电模块相结合,以实现水电联产.在1个标准太阳光照下,真实海水的蒸发率和发电输出功率分别达到2.23 kg m^(-2) h^(-1)和1.04 W m^(-2),展现了优越的太阳能利用能力.