高温熔融钢渣热闷热平衡分析及余热回收利用

对钢渣热闷过程中的热量平衡进行了分析和计算,提出了余热回收方案,并对经济效益进行了分析,为钢渣余热回收的进一步研究和实践打下了基础。     

高温熔融钢渣热闷热平衡分析及余热回收利用

对钢渣热闷过程中的热量平衡进行了分析和计算,提出了余热回收方案,并对经济效益进行了分析,为钢渣余热回收的进一步研究和实践打下了基础。     

钢渣处理与余热回收技术的分析

对国外和中国钢渣处理的余热回收技术和余热回收装置应用案例进行了大量列举、系统比较和分析。通过比较和分析表明：熔融钢渣中的余热可以通过各种不同的钢渣处理工艺,结合科学、经济、合理的热能回收技术将余热加以回收和利用,成果十分显著。同时,指出了由于受钢渣固有特性和物化条件的制约,目前钢渣余热资源的回收存在着许多问题,有待于钢铁行业和热能开发领域的研究者继续探讨和解决。最后,对钢渣余热回收的前景进行了展望,建议政府和相关领域予以足够的重视和支持。     

汽碎浅闷作热回收法处理转炉熔融钢渣

文章对钢渣的资源价值分析入手,探讨了钢渣利用的优先次序和发展方向.在综合分析目前主要钢渣利用技术优缺点的基础上,提出采用汽碎浅闷余热回收法来处理钢渣,并对汽碎浅闷余热回收法的原理、工艺流程、经济性等作了比较和阐述,总结了汽碎浅闷余热回收法的主要优点.     

化学法回收高炉熔渣显热的研究进展

高炉渣是高炉炼铁的主要副产品,含有大量显热,是一种很好的二次资源。然而,传统水淬粒化工艺对熔渣显热没有任何回收利用。针对高炉熔渣热量的回收问题,国内外在实验室进行了大量研究,这些研究大致可分为物理换热法和化学回收法。与物理法相比,化学法回收高炉熔渣显热更具有前景。本文详尽地对化学法回收高炉熔渣显热进行了评述,包括了利用甲烷循环反应、甲烷重整制氢、煤气化反应和高炉渣直接制备高附加值材料等。分析了各种方法的优劣,在此基础上,阐述了高炉熔渣显热回收需要解决的关键问题和发展趋势。     

从炼钢渣中回收铁的新方法

本文的主要目的是探索一种可持续的方法,回收钢渣中有价值的成分再利用.根据对钢渣回收利用的创新原理,使用热解重量分析法在1623～1823 K的温度范围内,在不同的气氛中对液态渣中的氧化亚铁氧化进行了实验研究.本实验中采用合成剂(二元和三元渣系)和工业炼钢渣,使用X射线衍射法进行反应产物的分析,并确认了通过氧化可将炼钢渣...     

钢渣处理方法的比较分析及综合利用

介绍和比较了当前钢渣处理的主要工艺方法。结果表明:我国钢渣的综合利用和余热回收仍处于研究开发阶段,没有广泛应用于工业生产中,开发一种合理利用资源的新型钢渣处理工艺迫在眉睫。     

从废旧锂离子电池中回收有价值金属的研究

以废旧的镍钴锰酸锂电池为原料,经过活性物质的分离、浸出、逐步化学沉淀等工序,有效回收了废旧锂离子电池中的有价值金属。采用H_2SO_4和还原剂(NH_4)_2SO_3对镍钴锰酸锂进行浸出试验,在最佳浸出条件下:H_2SO_4 1.0mol/L、(NH_4)_2SO_3 0.34mol/L、固液比25g/L、反应温度60℃、反应时间40min,Co、Ni、Mn、Li的浸出效率分别为97.61%、98.40%、97.91%和98.43%。然后采用共沉淀法回收浸出液中的镍、钴、锰,最后,通过添加饱和的Na_2CO_3回收母液中的Li+。     

国内外冶金渣显热回收

钢渣具有很高的温度(1450～1650℃),钢渣热焓约为1670MJ/t,属于高品质的余热资源,具有很高的回收价值。但目前,国内外冶金渣多以水淬法为主,热量无法回收利用。由于冶金渣用途很广,因此,熔渣能量的回收原则就是不仅要回收其余热资源,而且要便于炉渣的再利用,并且不产生环境污染。     

烧结过程余热资源高效回收与利用的热力学分析

烧结过程余热资源的高效回收与利用是目前降低烧结工序能耗的主要方向与途径之一。就本质而言,余 热回收与利用过程是一个能量转换与利用的过程,热力学分析是其重要研究手段。采用热力学第一定律和第二定 律,针对目前烧结余热利用方式,系统分析了烧结余热资源的产生、转换与利用等环节中各种形式的余热在数量上 的守恒和品质上的匹配关系,重点分析了各环节的热效率、火用 效率以及火用损失,藉此分析影响余热回收与利用的主 要因素及其制约环节,提出提高余热回收与利用的方法与途径。     

熔融钢铁渣干式粒化和显热回收技术的进展

 分析了钢铁熔渣显热回收的技术难点,因为硅酸盐类炉渣导热系数低而处理温度高,所以换热效果难以保证。介绍了连铸连轧法、滚筒法、搅拌法、风淬法、Merotec法等各种熔渣干式粒化 物理法显热回收工艺和气体重整、煤气化、直接生产产品等化学法显热回收的技术方案。指出效率不高是各种物理法热回收工艺不能工业化的原因。熔渣显热回收技术对中国钢铁工业的节能降耗很有意义。经过分析,离心粒化和化学法回收热能很有发展前途。     

焦化生产工艺废渣的综合利用

介绍焦化废渣的来源、性质及处理工艺的发展过程,重点介绍焦化废渣制造型煤炼焦的工艺,分析焦化废渣配型煤炼焦对焦炭质量的影响和经济效益。     

Thermodynamics and kinetics of coal gasification in a liquid iron bath

The thermodynamics and kinetics of the Molten-Iron-Pure-Gas (MIP) process used for coal gasification have been analyzed. In the MIP process, oxygen, fine-grained coal, and fluxes are injected into a liquid iron bath to produce a high temperature gas consisting of CO and H₂ plus a liquid basic slag. The sulfur is transferred from the coal to this slag. Computer calculations bearing in mind test conditions were used to determine equilibrium conditions as well as mass and energy balances; these indicated that the MIP process is technically feasible. The kinetics of the gasification process have been investigated by analyzing and assessing the basic reactions for a bottom-blowing MIP reactor. A comparison of all relevant reactions reveals that the dissolution of carbon in iron is the rate-determining step of the process. The bath turbulence induced by the injected gas and by the product gas results in intense mixing and dispersion of the reactants and their intermediate products. These phenomena create extremely large mass-transfer surfaces and extend the retention time of the reactants in the liquid iron bath. This results in high conversion rates relative to the volume of the MIP reactor.     

首钢京唐炼铁余热余能回收及潜力

京唐炼铁余热余能占炼铁工序能耗的60%左右,分布于热风炉、高炉煤气除尘、炉前除尘、渣处理和高炉本体冷却水等系统。重点分析现有工艺技术流程,通过高炉煤气回收、干式TRT和热风炉烟气预热空煤气及制粉三项利用技术,已实现炼铁主要余热余能回收80.8%,指出热风炉烟气和高炉煤气物理显热利用率仅为30%～40%,还有待进一步提高。同时,以末端温度为基础分析了各项低品位余热潜力尚有65.9kgce/t,并提出有效利用放散高炉煤气、热风炉烟气和冲渣水余热等措施和建议,为余热梯级回收和合理高效利用提供依据。     

粗煤气铁矿颗粒床高温除尘联产直接还原铁工艺及估算

在煤灰熔点高于直接还原铁还原温度200℃的条件下,以直接还原竖炉作为移动颗粒床除尘器为核心技术的3段连续除尘,以铁矿煤球团为直接还原铁原料和移动颗粒床除尘颗粒,粗煤气显热可以直接用于生产直接还原铁。粗煤气显热约占煤炭气化热值的13%,估算联产直接还原铁显热利用效率可达70%以上,与现有的粗煤气废锅发电比,综合热效率提高约2倍,直接还原铁能耗303kg（C）/t.Fe,可以实现温室气体近零排放,减排CO₂约1.7t/t.Fe。可以在不减少粗煤气化学热能（H₂+CO）,联产直接还原铁的同时解决粗煤气的高温除尘与净化问题。     

Processing Ash and Slag Wastes from Thermal Power Stations. Part 2

For existing coal-fired power plants, current methods of utilizing ash and slag waste may be considered in addressing new environmental and economic risks. However, for new power sources, environmental considerations are much more important in selecting the coal-combustion technology. Technology based on a circulating fluidized bed is sometimes cited as the most promising approach to environmentally sound coal combustion. It permits significant decrease in emissions of sulfur and nitrogen oxides beyond the boiler, but is of no help in processing ash and slag waste. For waste disposal, a different approach is recommended for new plants or the upgrading of coal-fired plants: instead of coal combustion in a gas flux or a fluidized bed, combustion in bubbling slag melt. Such methods are described. The basic characteristics of pulverized-coal combustion and combustion in slag melt are compared. Two basic approaches to the development of coal-based power generation are proposed: coal combustion with supercritical steam parameters; and gas generation with a hybrid (steam + gas) power-generating cycle based on gasification of solid fuels. The electrical efficiency of steam-based plants may be increased from 30–36 to 44–45% with supercritical steam parameters; and to 50–55% when using a hybrid steam–gas cycle. The proposed industrial system for coal gasification in slag melt increases the overall electrical efficiency. The environmental and economic efficiency of carbon gasification is demonstrated. It is simple to produce components from slag by casting. The cast slag–coal components are of considerably higher quality than analogous cement–sand components with added fly ash. The ease of switching from one type of casting to another permits rapid response to market demand.     

Research on characteristics and modelling estimation of molten BF slag viscosity in the process of slag waste heat recovery

The object of this study was to explore the effects of basicity (CaO/SiO₂ ratio), MgO and Al₂O₃ on viscosity and melting temperature of molten slag in the process of coal gasification with blast furnace (BF) slag as heat carrier to recover the waste heat. The results showed that the viscosity and melting temperature of BF slag decreased first and then increased with CaO/SiO₂ ratio increasing, and the suitable CaO/SiO₂ ratio was 1.10–1.20. Both viscosity and melting temperature increased with the increasing of MgO and Al₂O₃ in the slag, which should be lower than 8.22 and 11.00%, respectively. What is more, the viscosity estimation model for molten BF slag was established according to the Urbain model and experimental data of slag viscosity. In the model, the activation energy was calculated using slag compositions based on the redefine of material types in the slag, and the temperature was described by the Weymann–Frenkel equation. The viscosity of BF slag system estimated by proposed viscosity estimation model (modified Urbain model) fitted well with the experimental data and the mean deviation was about 17.98%.