Change in Carbon Dioxide （CO2） Emissions From Energy Use in China＇s Iron and Steel Industry

 As the largest energy consuming manufacturing sector and one of the most important sources of carbon dioxide (CO2) emissions, the China′s iron and steel industry has paid attention to the study of changing trend and influencing factors of CO2 emissions from energy use. The logarithmic mean Divisia index (LMDI) technique is used to decompose total change in CO2 emissions into four factors: emission factor effect, energy structure effect, energy consumption effect, and steel production effect. The results show that the steel production effect is the major factor which is responsible for the rise in CO2 emissions; whereas the energy consumption effect contributes most to the reduction in CO2 emissions. And the emission factor effect makes a weak negative contribution to the increase of CO2 emissions. To find out the detailed relationship between change in energy consumption or steel production and change in CO2 emissions, the correlation equations are also proposed.     

基于LMDI?STIRPAT模型的中国钢铁行业碳达峰路径研究

基于排放因子法核算中国钢铁行业2000—2019年碳排放,运用两阶段对数平均迪式分解法（LMDI）和STIRPAT模型分析碳排放增长的影响因素和2030年碳排放。结果表明,碳排放持续增长,2014年达到阶段峰值18.48亿吨。规模因素是碳排放增加的主要原因,能源强度是最大的抑制因素。情景分析表明,基准情景下将在2025年达峰,碳排放量为19.04亿吨;低碳情景下碳达峰时间为2021年,碳排放量为18.67亿吨;强低碳情景已于2020年达到碳排放峰值,碳排放量为18.52亿吨;快速发展情景则无法在2030年前实现碳达峰。      

联合钢厂采用无碳排放的ENERGIRON直接还原方案减少温室气体的排放

在基于高炉冶炼的联合企业中,始终有一些过剩的焦炉煤气、转炉煤气和高炉炉顶煤气,通常这些煤气用于电厂发电。另一种替代方法是使用这些现有的能源气体生产直接还原铁(DRI),将其作为金属化炉料加入高炉,提高粗钢产量,以减少化石燃料单耗。优化利用主要的化石燃料可以显著降低吨钢CO2排放量。采用传统的BF-BOF流程,即使在优化工艺流程的基础上,吨钢CO2排放量也有1.7～1.8t左右。而用产自天然气、焦炉煤气和高炉炉顶煤气的DRI作为金属化炉料加入高炉或电炉,却可显著降低CO2排放量。     

钢铁企业系统节能减排过程集成研究进展

论述了过程集成方法在过程工业领域的应用及研究进展。指出钢铁工业是典型的过程工业系统,根据其能源消耗、污染物排放的特点,以生产工序、生产流程和联合企业为研究对象,依据能量流、物质流和污染流输入输出关系构建了钢铁生产过程集成模型,并分析了影响钢铁工业节能减排的因素。结果表明通过过程集成可以实现钢铁工业系统节能减排,同时优化钢铁生产流程的物质流和能量流结构,进一步分析提高能源效率,降低CO2等污染物排放的潜力、途径和技术措施。     

中国钢铁工业流程结构、能耗和排放长期情景预测

为了准确预报我国钢铁工业未来生产结构、能耗和排放情况,构建了钢铁生产、加工、消费、折旧的全生命周期模型和基于人均钢铁存储量的产量预测模型,结合工序能耗和排放特征,针对基准、折旧寿命延长、废钢回收率提升、能源效率提高及综合等五种情景进行了情景预测.中国钢铁产量、能耗和排放会历经一个峰值后下降,电炉短流程会逐渐替代高炉长流程成为主流.流程结构转变是未来中国钢铁行业节能减排的关键"红利",而节能技术的作用在后期越发凸显.中国钢铁行业要达到2050年减排一半的目标,需结合综合情景实施生产结构调整、废钢回收、节能减排技术推广等相应措施.      

首钢京唐钢铁公司绿色低碳钢铁生产流程解析

 中国钢铁行业面临着资源能源短缺、市场盈利下降和生态环境制约三个方面的压力与挑战,在低碳循环经济成为当前社会发展主趋势的情况下,钢铁企业需要向低碳、绿色生产的方向转型升级。以京唐钢铁公司2015年上半年的生产调研为基础,计算京唐钢铁公司生产过程的能耗、CO2排放情况,并对钢铁生产过程能量流运行、废弃物处理与能源转换情况进行分析,为其他钢铁企业减少CO2排放、节约能源、保护环境提供一个参照。研究表明,京唐钢铁公司吨钢综合能耗为604.5 kg,吨钢CO2排放为2.165 t,与产品结构相类似的宝钢和武钢相比,能耗水平位于行业先进水平;基于钢铁生产的能量流分析表明,京唐钢铁公司通过采用干熄焦发电、煤气干法除尘、TRT余压发电等先进技术,实现吨钢余热余能回收136.26 kg,余热余能回收率为48.31%,高出全国平均水平10.89%;京唐钢铁公司基于循环理念,建立高效的煤气-电能转换中心和余热蒸汽回收利用中心,基本实现了煤气资源、固体废弃物资源、水资源的循环利用与废水零排放,生产过程中SO2、NO2、粉尘的全面达标排放。     

钢铁流程资源-能源-碳排放耦合关系及分析

 钢铁工业作为国民经济建设的基础性行业,在繁荣发展的同时带来了资源和能源消耗量大、CO₂排放高等问题,引起国内外重点关注。基于中国北方某钢铁企业,以3种典型的耦合关系为例对钢铁生产过程的水资源-能源-碳排放耦合关系以及相关的影响因素进行了分析。节能供给曲线分析和生命周期水足迹分析结果表明,案例企业的能源消耗-水资源消耗-碳排放存在协同效应。例如在节能技术视角下,19项具有成本效益的节能技术在减少能耗6.01 GJ/t的同时,还可协同减少工业新水消耗1.35 m3/t、水足迹4.81 m3/t以及CO₂排放640.36 kg/t。进一步分析了耦合关系的主要影响因素,即电力消费结构、废钢投入率和节能技术参数变化的影响。该研究为中国钢铁工业可持续发展提供理论依据和重要参考。     

Embodied Energy and Gas Emissions of Retaining Wall Structures

The embodied energy (EE) and gas emissions of four design alternatives for an embankment retaining wall system are analyzed for a hypothetical highway construction project. The airborne emissions considered are carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), sulphur oxides (SOX), and nitrogen oxides (NOX). The process stages considered in this study are the initial materials production, transportation of construction machineries and materials, machinery operation during installation, and machinery depreciations. The objectives are (1)?to determine whether there are statistically significant differences among the structural alternatives; (2)?to understand the relative proportions of impacts for the process stages within each design; (3)?to contextualize the impacts to other aspects in life by comparing the computed EE values to household energy consumption and car emission values; and (4)?to examine the validity of the adopted EE as an environmental impact indicator through comparison with the amount of gas emissions. For the project considered in this study, the calculated results indicate that propped steel sheet pile wall and minipile wall systems have less embodied energy and gas emissions than cantilever steel tubular wall and secant concrete pile wall systems. The difference in CO2 emission for the retaining wall of 100?m length between the most and least environmentally preferable wall design is equivalent to an average 2.0?L family car being driven for 6.2?million miles (or 62 cars with a mileage of 10,000??miles/year for 10?years). The impacts in construction are generally notable and careful consideration and optimization of designs will reduce such impacts. The use of recycled steel or steel pile as reinforcement bar is effective in reducing the environmental impact. The embodied energy value of a given design is correlated to the amount of gas emissions.     

石灰石替代石灰作炼钢造渣原料节能减排估算

对比分析了石灰石造渣炼钢工艺相较于现行石灰造渣炼钢工艺的节能减排环节,采用IPCC提供的排放因子法计算了每个环节的节能减排量,结果表明,石灰石造渣炼钢工艺较现行工艺节省能耗18.32kg(标煤)/t(钢),相当于减排45.80kgCO2/t(钢);减排粉尘量约5.34g/t(钢),SO2约14.15g/t(钢)、NOx约70.77g/t(钢),减排可致灰霾颗粒物127.39g/t(钢)。     

Material Metabolism and Environmental Emissions of BF-BOF and EAF Steel Production Routes

As an energy-intensive industry, iron and steel production are suffering from the resource and environmental issues. Blast furnace—basic oxygen furnace (BF-BOF) process and electric arc furnace (EAF) process are the two most common routes of steel production. Therefore, it is very important to quantify the industrial metabolism for the two routes. In this work, material flow analysis is used to comparatively investigate the energy efficiency, material efficiency, and emissions intensity at the enterprise level. The results show that the total energy consumption and material consumption per ton of steel of the BF-BOF route are 2.8 and 11 times larger than those of the EAF route, respectively. In addition, the emission intensities of dust, CO₂, SO₂, NO₂ and CO of the BF-BOF route are 7.7, 2.6, 92.6, 33.5, and 12.0 times greater than those of the EAF route, respectively. To achieve a more sustainable steel industry, some policy recommendations are put forward finally.     

炼铁系统物质流与能量流分析

炼铁系统的能源消耗占钢铁联合企业总能耗的60%以上,提高炼铁系统的能源效率已成为解决钢铁工业这些问题最有效的方法之一。本文主要从炼铁系统物质流和能量流的角度出发,分析了炼铁系统（包括烧结和高炉）的资源和能源消耗情况,并以唐钢南区炼铁系统为例,计算了其炼铁系统由含碳能源引起的CO₂排放量。     

中国钢铁工业节能减排潜力及能效提升途径

 钢铁工业是典型的资源能源密集型行业，是节能减排重点行业之一。总结了中国钢铁工业“十二五”以来所取得的节能减排进展及存在的问题，采用动态物质流分析方法，构建了钢需求量和废钢回收量预测模型，基于35项重点节能减排技术评估，结合能源消耗与CO2排放模型，分析了中国钢铁工业到2050年的节能减排潜力并分析了各因素的影响。在此基础上提出了提升中国钢铁工业能效的若干途径，为钢铁工业的绿色低碳转型、可持续发展提供理论指导。     

A Brief Overview of Low CO2 Emission Technologies for Iron & Steel Making

 The global steel production has been growing for the last 50 years, from 200 million metric tons in 1950s to 1,240 million metric tons in 2006. Iron and steelmaking industry is one of the most energy-intensive industries, with an annual energy consumption of about 24 EJ, 5% of the world's total energy consumption. The steel industry accounts for 3-4% of total world greenhouse gas emissions. While enhancing energy efficiency could be a short-term approach for the steel industry to reduce greenhouse gas emission, the long-term approaches to achieve a significant reduction in CO2 emissions from the steel industry would be through (1) developing and applying CO2 breakthrough technologies for iron and steelmaking, and (2) increasing use of renewable energy (in particular, bio-energy) for iron and steelmaking. This paper presents an overview of new CO2 breakthrough technologies for iron and steelmaking, and the current research and development for the use of biomass and bio-fuels as substitutes for coke, coal and natural gas in various iron and steelmaking processes including iron-ore sintering, blast furnace operations, and new iron and steelmaking processes. The key challenges for utilization of bio-energy on a large scale for iron and steelmaking are also discussed in this paper.     

肯布拉港钢厂能源消耗和CO2排放模型

钢铁工业正朝着大幅降低能源消耗和CO2排放的方向努力。了解不同操作方案对节能减排的影响十分重要。综合数学模型可以作为评估不同方案的有效工具。博思格钢铁公司在肯布拉港钢厂(PKSW)采用了一种"钢铁联合企业能量和排放模型"(ISEEM),该模型以PKSW钢厂的物料和能量平衡为基础,范围是"从原料进厂到产品输出",即包括原料准备、高炉、炼钢、轧钢及其公辅设施。ISEEM以Aspen Custom Modeller(ACM)为平台,使用一种目标定位过程建模语言,能列出系列方程,描述各个单元操作。描述了ISEEM模型的关键要素及其对PKSW钢厂不同方案和基准操作的应用评估。同时还简述了博思格钢铁公司参与的两个CO2减排项目。     

Influence of production parameters on greenhouse-gas emissions in ferrous metallurgy

The influence of the production parameters on greenhouse-gas emissions in ferrous metallurgy is demonstrated. Relevant factors include change in plant output, product range, the technology for steel smelting and casting, and the composition in ingot casting. The replacement of open-hearth technology by converters will reduce carbon-dioxide emissions and the energy consumption in steel production only if continuous casting is introduced and the hot-metal consumption in converter smelting is reduced.     

Implementation of a greenhouse gas reduction roadmap for steel producing companies

This paper shall show an economic feasible approach to implement greenhouse gas（GHG） reduction measures into steel companies. The goal to improve energy consumption is directly linked to the reduction of GHG emissions and therefore directly in correlation with the economic viability. A baseline scenario of the considered reference system and of the respective reference year has to be defined, mapped and analysed. In a second step an analysis of the same operation using available and prospected best available technology （BAT） processes is carried out to generate a basis for a benchmark system. The identified reduction potentials are reported and the GHG emission reductions are put into relation to the investment cost of the new process technologies/process adaption to be implemented.This economic feasibility calculation is necessary to realise a cost efficient GHG reduction roadmap implementation into the company’s business operations. The GHG reduction roadmap is developed using the abatement curve concept to get an indication of " low hanging fruits" and for establishing a sequence for implementing carbon emission reductions measures. The scope of that approach can be extended by including further important environmental parameters like NOx, SO₂,CO,dust,heavy metal emissions in air as well as production residues.That gives in the end a broader picture and more starting points to improve the overall environmental performance of steel producing companies beyond the GHG emissions and energy consumption.     

中国钢铁工业节能减排现状及对策

为促进我国钢铁工业节能减排工作的进行,通过和先进国家比较分析的方法对我国钢铁工业节能减排现状进行了研究,研究发现我国钢铁行业耗能总量约占总能耗的18%,吨钢综合能耗为629.93 kg标煤,重点企业能耗水平已接近先进国家水平,CO2排放总量为世界钢铁工业的51%.我国节能技术的开发应用有很大空间,建议提高电炉炼钢比例,...     

电弧炉电能需求的生产实践与评价

电耗是电弧炉的重要技术指标之一,在当前发电行业背景下,降低电弧炉电耗具有显著的经济和环境效益。根据典型电弧炉企业生产数据,系统分析各项工艺参数与电耗之间的关系,并进一步评价了各种方法降低电耗的环境效益。结果表明,优化供电制度和强化供氧是具有良好环境效益的节电手段。对于连续加料电弧炉,天然气喷吹对降低电耗的作用被极大减弱,天然气消耗与电耗的相关系数为-1.13 kW·h/m³,其应用不利于CO₂减排。尽管兑加铁水可以显著降低电耗,但是兑加40%(质量分数)铁水的连续加料电弧炉能耗和碳排放量分别是全废钢连续加料电弧炉的2.25和2.50倍,不利于推动钢铁工业节能减排工作。因此,降低电弧炉电耗需要通过增加电弧炉中化学能和物理热的供应及减少能量损失的手段来实现。     

钢铁行业能源精准化管控集成系统的开发

在信息技术综合服务平台的基础上,以钢铁行业节能环保为目标,通过钢铁行业节能试验工程建设、钢铁企业能源精准化设计、钢铁企业能源综合管控、钢铁行业能源信息咨询服务四大平台的建设,开发出钢铁行业能源精准化管控集成系统。此项目的实施可降低钢铁企业吨钢综合能耗3%~5%,吨钢节省18.1kg标准煤,吨钢减少CO2排放超过45kg。     

The Contribution of Niobium Bearing Steels and Enhanced Sustainability

With the growing concern for the environmental impact of greenhouse gases and the rapid depletion of important resources,the use of Nb-bearing steels for advanced high strength steel applications can reduce raw material usage and the carbon footprint.The conservation and more efficient use of ironmaking and steelmaking raw materials is an urgent issue for steel producers globally.Recently-developed Nb-microalloyed steel applications provide a more effective product design and reduce CO 2 emissions and energy consumption per tonne of steel.A sustainability structural steelstudy presents the positive cost and reduced environmental impact of Nb-microalloyed steels.This analysis compares the CO 2 emission reduction and energy savings in the steelmaking process melted in both the Basic Oxygen Furnace (BOF) and the Electric Arc Furnace (EAF).Nb-microalloyed structural steels offer the opportunity to reduce the total weight of a given structure compared to a non-microalloyed steel construction.Generally,one considers the savings associated with less material and lower construction costs.In addition,there is an environmental benefit in the reduction in emissions (kilograms of CO 2) and less energy consumption (GJ) due to the fact that less steel is melted.Plus,there are lighter sections and less material weight in the final end user design which reduces transportation and fabrication costs.A forecasted trend is presented which introduces an increased usage of microalloyed steel grades to replace traditional commodity-type non-alloyed higher carbon-manganese grades for environmental benefits and significant cost reduction.