钢铁联合企业CO2排放研究综述

摘 要：回顾了近年来国内外研究钢铁联合企业CO₂排放的文献,建立了钢铁生产过程碳素流模型;总结和分析了钢铁联合工业影响CO₂排放因素;介绍了国外利用reMIND和CLPEX建立的过程集成优化分析生产成本和CO₂排放量的模型;总结了钢铁联合企业CO₂排放量的估算方法和注意事项;提出我国钢铁联合企业目前应该加快建立适合本国钢铁联合企业温室气体排放计算标准和方法;展望了钢铁联合企业研究CO₂排放的研究方向。     

钢铁生产过程二氧化碳排放计算方法与实践

 钢铁生产过程二氧化碳排放量的精确计算是钢铁行业节能减排的基础。对钢铁生产流程二氧化碳排放的3种常用温室气体排放计算方法进行介绍,并基于A钢厂2014年的生产数据进行计算和分析对比。《省级温室气体清单编制指南》、《钢铁碳排放指南》两种计算方法都是基于投入产出的统计方法,两者温室气体计算结果数值相近,前者吨钢二氧化碳排放结果为2.116 t,后者吨钢二氧化碳排放结果为2.013 t ,后一种方法在计算时考虑了固碳产品的抵扣,所以结果比前种方法结果偏小。基于ISO标准的钢铁产品生命周期计算方法,计算边界从铁矿石、煤炭等原材料的采掘、洗选、运输,焦化,烧结,高炉,炼钢,轧制等直到钢铁产品的出厂,计算结果吨钢产品二氧化碳排放量为2.309 t,相比前两种方法计算结果数值较大,这是因为在计算时包含了铁矿石、煤炭等在开采、洗选、运输阶段产生的二氧化碳。     

气候变化与钢铁工业脱碳化发展

 中国政府高度重视气候变化问题,积极主动地做出了减排承诺。钢铁行业作为工业的重要领域,是能源消费大户,同时也是CO₂排放大户。对中国钢铁工业CO₂排放现状分析表明,中国钢铁工业吨钢CO₂排放量下降明显,CO₂排放总量在2014年已经达到峰值,随后呈下降趋势,但由于粗钢产量巨大,钢铁工业的CO₂排放量占全国CO₂排放总量仍然较高,必须走脱碳化发展的道路。通过对钢铁工业脱碳化发展策略和技术的分析,表明有策略地推进并提高全废钢电炉流程的比例是当前最为实际的钢铁工业脱碳化发展途径。     

热压铁块降低高炉CO2排放量的探究

热压块铁(HBI),品位在92%～93%,具有高纯净、低有害杂质、品质均匀、强度高、粉化率低等优点，直接装入高炉，可提高铁水产量，同时也可降低高炉单耗，节焦、增产效果明显。以国内某1 580 m³高炉为研究对象，建立了高炉工序的CO₂排放计算模型，计算出高炉工序CO₂排放量为1192.109 kg/t铁，吨铁CO₂排放量为1618.96 kg。对高炉工序CO₂排放量计算结果分析，焦炭的CO₂排放量高达73.52%,要降低CO₂的排放的关键在于减少焦炭的使用。随着加入热压铁块的量增大，吨铁CO₂减排量增大，从而实现了减少CO₂排放。     

CO2在钢铁工业资源利用现状

钢铁生产过程CO₂的资源利用问题将对我国CO₂减排任务的完成起到重要作用.以CO₂在钢铁工业中的资源化利用为出发点,分析了国内外CO₂气体作为反应气体、搅拌气体及保护气体等在钢铁生产过程中的应用现状. CO₂用作反应气体主要应用在BOF转炉炼钢、不锈钢生产及钢渣碳酸化处理;CO₂用作搅拌气体主要应用于转炉底吹、钢包搅拌及LF炉精炼;CO₂用作保护气主要应用在出钢、中间包及连铸等工序.利用CO₂用于钢铁生产具有成本低、热力学条件好、密度大、搅拌能力强及实现CO₂资源利用等优点,CO₂喷吹之后反应体系中CO₂的利用率需进一步研究.      

铝电解生产过程全氟化碳排放现状与分析

全氟化碳(PFCs)是目前被认为增温潜势非常强的温室气体，铝电解生产过程中产生的全氟化碳包括CF₄和C₂F₆。我国电解铝产量连续十多年位居世界首位，降低铝电解生产过程中PFCs排放是铝工业温室气体减排的路径之一。本文分析了铝电解PFCs的产生机理和排放情况，并以某企业300 kA系列电解槽为例，测量计算其PFCs的CO₂当量排放，并与按照指南缺省值核算的PFCs排放数据进行对比。对比结果表明，按缺省值计算的PFCs排放量为0.252 3 t CO₂e/t-Al,远小于测量值0.883 9 t CO₂e/t-Al,无法体现企业的真正PFCs排放情况。根据铝电解析出碳氟化合物的反应机理，降低铝电解生产PFCs排放的直接途径是减少阳极效应次数和缩短效应时间。因此，为了减少PFCs排放，从电解槽优化设计、槽控系统升级、工艺技术优化、大宗原料把控、设备运行维护等建方面提出了建议。     

CO2在炼钢工艺中的资源化利用现状与展望

将CO₂用于炼钢工艺可实现对CO₂资源化利用，是一种绿色化、低成本、高效率和易实现的冶炼技术。本文以采用CO₂炼钢工艺为立足点，介绍了近年来CO₂在转炉、电弧炉等流程的应用研究现状和发展情况。同时，结合基于钢铁企业的实际运用情况，概述了CO₂资源化利用在炼钢过程中的可行性和实际效果。CO₂可作为反应气体、保护气体、搅拌气体应用在炼钢工艺过程中，具有生产成本低、热力学条件好、搅拌能力强等优点，应用前景非常广阔。实际生产表明，采用CO₂炼钢可提高铁水脱磷率5%～7%，吨钢节约生产成本9元以上。CO₂在炼钢工艺中的资源化利用将是实现我国钢铁行业高效率、低成本减排的重点研究方向之一。以我国年产粗钢10亿t估算，采用CO₂炼钢工艺可降低钢铁行业CO₂总排放量约5%左右。     

典型钢铁制造流程碳排放及碳中和实施路径

高炉-转炉钢铁生产流程是典型的钢铁制造流程,也是典型的铁-煤化工过程,能耗高、碳排放量大,是中国钢铁行业实现碳中和目标的重点领域。2020年,由该流程生产的钢产量占全国粗钢产量的90%以上,是钢铁行业重要的CO₂排放源,因此,以典型高炉-转炉钢铁流程为主的企业碳排放计算和碳中和路径研究引起重视。目前国内外有多种针对钢铁企业碳排放的计算方法,但不同CO₂计算边界和方法对企业CO₂排放结果差异较大,影响因素也不同。剖析了钢铁生产流程的碳排放特征,以典型高炉-转炉制造流程为例,从系统边界、碳排放核算方法以及影响因素等角度全方位分析了钢铁制造流程碳排放,核算了不同方法下390万t和550万t钢铁企业的碳排放量,并对比了不同核算方法的差异性。结果表明,A企业和B企业铁前工序的CO₂排放占总碳排放的比例分别为60.99%和54.12%,减少钢铁制造流程CO₂排放应优先考虑焦化、烧结和炼铁工序;影响钢铁制造流程减排的因素主要包括化石燃料的消耗、能源的回收率、自发电的比例和碳排放因子的选取,其...     

钢厂生产流程与大气排放

钢铁是一种重要的材料,其生产过程依赖于矿物资源和各类能源,由此构成了钢铁生产过程对环境的多层次排放。从保护生态环境的角度出发,研究钢铁材料从采矿、钢铁制造、使用到废弃、回收、再生的整个过程对环境的影响,对于重新认识和评估钢铁工艺流程是十分重要的。本文在分析钢厂对环境的影响层次和钢厂环保技术内涵的基础上,分析了两类模型工厂：高炉—转炉—连铸—热轧工艺流程和电炉—薄板坯连铸—热轧工艺流程,分别对其买煤买电和只买煤不买电两种方案的吨钢气体排放量和万元产值排放量进行了计算、比较,从钢厂生产过程对大气排放的角度为钢铁制造流程的整体优化提供参考。     

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。     

Steel’s CO2 balance—a contribution to climate protection

Steel making is energy and material intensive.That is why steel is always demonized and confronted with incriminations and requirements for reduction of its environmental impact.Those pure demands-like for emission trading are short-sighted as they do not base on an integrated approach.Instead they merely consider CO₂ emissions during the production process.A forward-looking,global climate and environmental policy needs a sustainable life cycle approach.Therefore it must for example also take into account the contribution of steel towards cutting emissions in its application-in the energy.automotive and household sectors.Steel will play a key role in climate protection. One-third of the remaining CO₂ reduction target planned in Germany by 2020 can only be achieved with the help of innovative steel products and their applications.This is the conclusion of an independent study by The Boston Consulting Group（BCG） on behalf of Steel Institute VDEh,and German Steel Federation.The study compares CO₂ savings from important innovative steel applications（such as more efficient power stations,wind turbines,or lighter vehicles） with CO₂ emissions caused by steel production. By adopting this comprehensive perspective,the study for the first time provides a CO₂ balance for the material steel by comparing the CO₂ reductions made possible through innovative steel applications with the CO₂ emissions resulting from steel production.The balance was calculated on the basis of eight selected innovative steel applications in Germany for the period 2007 to 2020,whereby the CO₂ emissions caused by steel production were considered throughout the entire life cycle of the particular steel use.For the selected examples,the use of innovative steels resulted in a total savings potential of 74 Mt of CO₂ in 2020.The calculations are based on conservative assumptions;for example without counting of potentials by exported steel or by comparison with competitive materials. The production of steel in Germany,including the extraction of raw materials,transports and further processing, causes annual emissions of approx.67 Mt CO₂ This can be more than compensated by the above mentioned CO₂ savings.The balance is even more positive if one only considers the emissions of about 12 Mt/a CO₂ caused by the selected eight steel applications.Innovative steel use thus saves six times as much CO₂ as is generated by its production. Steel is part of the story and helps to achieve CO₂ reduction targets.On this basis the steel industry should start up with a new global approach to be accepted as a CO₂ killer,too,instead of being the devil.This needs a political discussion on an integrated approach taking into account the whole life cycle,which finally can lead away from stringent emission caps or incompatible emissions trading systems for the different regions.     

晋南钢铁高炉喷吹富氢气体工业化实践

 钢铁工业是中国制造业中碳排放量最高的行业,碳排放占全国碳排放总量的15%左右。高炉是钢铁工业碳消耗量最大的工序,碳消耗占钢铁流程总碳消耗的70%以上,减少高炉冶炼碳消耗是降低钢铁工业碳排放的最有效措施。高炉喷吹富氢气体不但可以提高冶炼效率,减少污染物排放,而且可以减少焦炭或煤粉消耗,从源头上降低高炉冶炼碳消耗,从而减少碳排放。以山西晋南钢铁两座1 860 m3高炉风口喷吹富氢气体工业化生产数据为例,详细研究了高炉喷吹富氢气体对燃料比、风口理论燃烧温度、炉腹煤气量、H₂利用率以及CO₂排放量的影响。结果表明,喷吹富氢气体可以显著降低高炉固体燃料消耗,在吨铁富氢气体喷吹量为65 m3条件下,富氢气体与固体燃料的置换比为0.49 kg/m3;风口喷吹富氢气体降低了风口理论燃烧温度,吨铁每喷吹1 m3富氢气体,风口理论燃烧温度降低约1.5 ℃,高炉鼓风量和炉腹煤气量都少量降低;喷吹富氢气体以后,炉内H₂的利用率平均为37.3%,CO的利用率约为43.2%;吨铁CO₂排放量可以降低80 kg左右,高炉CO₂排放降低了5.6%,取得了较好的经济、环境和减污降碳效果。     

Emission Mitigation of CO2 in Steel Industry: Current Status and Future Scenarios

The sustainable development against global warming is a challenge faced by societies at global level. For steel industry, the pressure of reducing CO₂ emission is likely to last many years. During the past decades, the CO₂ emission per ton steel has been reduced mainly due to the improvement of energy efficiency. Entering the 21st century, the steel manufacturing route must have three functions, namely, production of high performance steel products, conversion of energy, and treatment of waste. In the near future, it is expected that existing BF-BOF and EAF routes will be improved, in order to produce high performance steels, increase the use of scrap, and integrate steel industry with other industries for mitigating CO₂ emission. In the long term, using carbon-free energy, reducing agents, and storing CO₂ securely or converting CO₂ into a harmless substance can be presumed for tremendous reduction in CO₂ emission.     

Carbon dioxide emissions reduction technology and its application prospects in the steel industry

Fossil-fuel burning greenhouse gas induced global warming has been recognized as global environmental problems,reduce and ultimately control the energy production in the use of CO₂ emissions, global energy production will be a major challenge.As a highly intensive materials and energy,iron and steel enterprises,need to be invested to produce one ton of steel about two tons of material and 0.7 t of standard coal energy,and while producing two tons of CO₂.Therefore,reducing CO₂ emissions from iron and steel industry has become the focus of the global steel industry.This paper describes an integrated domestic and international measures to control carbon dioxide emissions research progress and future technology trends, with emphasis on the domestic steel industry emissions of carbon dioxide status of technology development and industrialization of implementation of the proposed on this basis,including dry quenching technology, gas,power generation,coal moisture control technology,blast furnace injection plastics technology,the use of coking process for treating municipal waste plastics technology,sintering heat generation,low pressure saturated steam for power generation,metallurgical slag heat recovery technology,coke oven gas hydrogen technology and the other key technologies energy saving technologies,including the development,promotion and popularization of the steel industry in China will be the CO₂ emission reduction technology direction and focus.At this stage,the Chinese steel industry can be improved the energy efficiency and recycling of waste heat and energy,reduce unit GDP,CO₂ emissions;but in the long run,should increase CO₂ capture and storage on the input of technology can possible effective control of the adverse effects of CO₂ emissions.     

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.      

国内外钢铁行业低碳发展策略分析

在绿色化、低碳化发展的时代背景下，全球钢铁行业纷纷开展低碳研究工作，各类低碳技术层出不穷。首先概述了全球钢铁行业CO₂排放现状，以及主要产钢国家的碳减排目标，并对其低碳策略进行详细的分析，指出国际钢铁行业的低碳发展方向主要聚焦于发展电炉流程、氢冶金、碳捕集利用与封存和清洁能源利用等方面。随后聚焦我国钢铁行业碳排放现状，梳理了中国钢铁行业实现“双碳”目标的应对策略，指出减量化发展、流程结构调整是未来我国钢铁行业低碳发展的主攻方向。最后，为了使前文所提的宏观策略更加具体化，又选取我国某一典型钢铁企业，以其技术特点、地理位置、资源禀赋、发展规划为主要依据，针对性地分析并提出了7条适合该企业的减排路径，为其绿色低碳发展指明方向。      

福建三钢集团节能降碳进展及碳减排路径

系统总结了福建三钢集团“十三五”期间节能降碳工作所取得的卓越成绩,并剖析了三钢集团在原料结构调整、降低高炉燃料比、二次能源回收、煤气高值化利用以及系统节能降碳等方面的措施和取得的效果。通过推进结构节能、技术节能和管理节能,全面提升了企业的能效水平。“十三五”期间,铁钢比下降了0.2,高炉燃料比下降了21.66 kg/t,吨钢综合能耗下降了1.30%,吨钢CO₂排放量下降了4.98%。另外,还对三钢集团碳减排规划进行了介绍,为其他钢铁企业绿色低碳发展提供借鉴。     

氢气气基竖炉-电炉短流程环境影响分析

氢冶金是中国钢铁行业实现低碳绿色化转型升级的有效途径之一,基于煤制氢技术的气基竖炉-电炉短流程是一种典型的氢冶金工艺,具有广阔的发展前景。采用生命周期评价法(LCA)对煤制氢-气基竖炉-电炉短流程环境影响进行了分析,并对比研究了短流程与传统高炉-转炉(BF-BOF)长流程的环境性能。结果表明,煤制氢-气基竖炉-电炉短流程LCA结果为2.56×10-11,其中GWP₁₀₀(全球变暖潜值)和POCP(光化学臭氧合成潜值)分别贡献54.16%和36.76%;煤气脱碳和电炉电能消耗是造成碳排放和能源消耗的主要原因;短流程整体评价结果仅为BF-BOF流程的27.41%,吨钢CO₂排放和能耗可分别减少53.75%和47.45%,环境性能明显优于传统长流程。