【作者】 胡睿；

【导师】 张群；

【作者基本信息】 北京科技大学 ， 管理科学与工程， 2016， 博士

【摘要】 作为世界上最大的发展中国家,中国近年来的发展有目共睹。伴随着国家实力的日益增强,发展带来的环境影响也日益严重。我国以钢铁企业为代表的重工业在国家建设中起到了至关重要的作用,同时也带来了不容忽视的能源消耗和碳排放问题。2014年,我国钢铁行业粗钢产量为8.23亿吨,已经连续18年位居世界第一。同年,我国吨钢综合能耗降至584.7千克标煤/吨钢。虽然同比有所下降,但绝对值仍处于世界较高水平。针对我国钢铁行业高能耗、高排放的现状,本研究利用碳素流分析的方法对冶金过程中碳元素足迹进行了追踪,利用系统动力学模型对长流程钢铁生产的主要工序进行了仿真,并通过情景分析试图寻找到适合中国钢铁工业发展的低碳道路。具体来讲,本研究主要从以下五个方面展开：首先,从背景及意义的角度入手,介绍了本研究开展的必要性和可行性,并对钢铁行业可持续发展、钢铁行业碳足迹研究和主要方法系统动力学等领域已有的研究成果进行了总结概述；第二,进行了基于能量流分析的钢铁行业低碳生产关键影响因素的选取,找到了铁钢比、技术推广和煤气回收三个主要因素。用到的方法是AHP(Analytic Hierarchy Process,层次分析法)方法,AHP评价体系评分来自三个方面：其一,收集来自钢铁研究院冶金经济研究所的专家的意见,对指标体系进行打分并记录分析；其二,钢铁企业能源管理中心和一线生产人员的访谈记录；其三,利用问卷和文献数据对指标的历史评价结果进行收集整理,辅助打分。最终综合两者意见得出三个关键指标；第三,构建钢铁企业“高炉／转炉”长流程炼钢的系统动力学模型。模型被命名为“生产-能耗-排放”模型,主要分为技术影响模块、废气回收模块、铁钢比模块和生产流程核心模块。模型中关系的建立和反馈回路的确定主要来源于国内千万吨级产能钢企的能源平衡表数据,2005至2014年《钢铁工业年鉴》以及部分网络资料整理；第四,针对上述三个影响因素制定三条可行策略：降低铁钢比、提高技术普及率和废气完全回收利用,并在构建的系统动力学模型对三种策略进行分情景的模拟仿真,分别从对能耗的影响和对碳排放的影响两方面进行研究。该部分是研究的一个核心,通过量化的参数对不同策略下钢铁行业的能耗和排放问题进行模拟,找出带有时间节点的低碳规划；第五,根据第四部分生成的结果,设计出具有中国特色的,符合行业特征的钢铁行业低碳生产路径图,并根据数据分析的结果给出相应的建议。该部分是研究的总结和升华,也是本研究的现实意义的体现。总体结论为：降低铁钢比是一项长远而有效的策略,应当保持高度关注并不断为其实现做准备,随着条件的成熟逐步推进；以高炉炼铁新技术为代表的减排降耗技术的不断研发和推广是一项可行且有效的策略,当前就应抓紧实施,且加大推进力度,争取达到全国钢铁行业100%应用节能技术生产,从而实现行业低碳生产的目标；煤气回收是一项已有成效但仍需加大投入的策略,尤其是高炉煤气和转炉煤气,两者由于热值不如焦炉煤气,所以回收率不如后者高,可以采用先回收存储后重复利用的方式,它可以作为一项中长期策略。在上述研究的过程中,本文总结提炼出的创新之处共有如下几点：第一,本研究给出了带有时间节点的我国钢铁企业低碳生产路线图,且路线图中的指标均为量化指标。之前,水泥等其他高能耗行业均已有成型的系统路线图,而钢铁行业在这方面的定性研究较多,定量研究几乎没有,因此本研究具有首创性和较强的可操作性。线路图分为三个阶段：首先进行新技术的推广,并加大力度进行废钢回收,称为“技术阶段”；接下来有足够的废钢积累后逐步提升电炉钢的比例,加大短流程炼钢的推广力度,称为“EAF(Electric Arc Furnace,电弧炉)阶段”；第三步即综合运用多种方法,实现低能耗,零排放,称为“零排放阶段”。第二,本研究对铁钢比、技术推广和废气回收三种手段在节能和减排两方面的作用进行了量化的对比研究。这三者对钢铁企业的能耗和排放的影响是大家都认可的,但是具体影响程度和之间的数量化关系则鲜有关注。本研究从系统的视角切入,利用系统动力学的方法将三者规划到一个整体中,结果证明这一尝试是可行并且有效的。研究发现,降低铁钢比在节能和减排两方面都是最为行之有效的,但是考虑到国内钢铁产品的回收周期还很长,废钢存量严重不足,所以进一步加强技术推广是当下最为可行的策略；第三,本研究在方法上综合了碳素流分析和系统动力学两种系统方法,取得了较好的结果。碳素流分析和系统动力学都是从整体的角度看问题,适合于复杂的、动态的、非线性的系统。而钢铁生产过程正是这样的一套体系。这种综合方法能够有效地抓住核心问题,规避干扰因素,得到有针对性地解决方案；第四,本研究提取了基于能量流分析的钢铁企业低碳生产关键因素。首先,该打分体系是建立在能量流分析的基础上的,是更有针对性和实际意义的一套指标体系；其次,由于钢铁行业是工业体系中的支柱,因此关于它的研究也较为成熟。因此,在本研究的关键因素寻找过程中,结合了已有文献的分析结果,利用已经得到认可的结果来补充和完善专家打分体系,使得后续的研究更加可信。总之,本研究利用能量流分析和系统动力学模型构建了钢铁企业生产模型,并对铁钢比、技术推广和废气回收三个关键因素对能源消耗和碳排放的影响进行了综合分析,给出了低碳生产路线图,并提供了相关的政策建议。更多还原

【Abstract】 As the largest developing country in the world, China’s development in recent years is obvious to all. With the growing strength of the country, the impact of the environment is also growing. The heavy industry, which is the representative by iron and steel enterprises in China, plays a vital role in the national construction, and it also brings up the problem of energy consumption and carbon emissions.The crude steel production in China’s was 8.23 tons in 2014, and it has been ranked first in the world for 18 consecutive years. At the same year, the comprehensive energy consumption per ton of steel in China fell to 584.7 kgce/ ton-steel. Although this number declines year-on-year, the absolute value is still at a relatively high level among the world’s main producers.Under this circumstance, this paper is trying to solve the problem of high energy consumption and emission in China’s iron and steel industry. This research applied the following methods:1) using carbon flow analysis to track the carbon footprint of the metallurgical process; 2) using system dynamics modelling to simulate the main process of the long process production. To be specific, this study mainly contains the following five aspects:Firstly, this study presented the background and the significance of energy consumption and emission control problem internationally. The necessity and feasibility of the research were also introduced. Besides, the literature review about the sustainable development in iron and steel industry, carbon footprint and system dynamics were also summarized in this part.Secondly, based on the energy flow analysis, three key factors of low carbon production were defined:the iron-steel ratio, the technology promotion and the secondary energy recovery. The judging matrix was given based on the data as follows:first, collecting the opinions from the experts from the Iron and Steel Research Institute; second, questionaires to front-line workers and official released data; third, using literature data assist the scoring. Finally, integrating scores from the three sources and define the key indicators.Thirdly, the system dynamics model of long process steel production was given. It described the "blast furnace/converter" mode in the steel industry. The model is mainly divided into three parts:the technology influence module, the waste gas recovery module and the core production module. The relationship between the parameters and the feedback loop were determined mainly by the energy balance data from a ten million capacity steel enterprises in China.Fourthly, simulation based on the system dynamics model was conducted and scenario analysis was completed. This part was the core of the research. Through the quantitative parameters, the energy consumption and emissions of steel industry under different strategies are simulated.Finally, according to the results of the fourth part, the low carbon roadmap with controlling node was presented. Moreover, the corresponding suggestions were brought up. This part was the summary and sublimation of the study, which also showed the realistic significance of this study.In the process of the above research, this paper summarizes the innovation points as follows:Firstly, this study gives a low carbon production road map of steel enterprises in China with controlling node, and the indicators in the road map are quantitative. In the past, there were roadmaps for other high energy consuming industries such as cement. While in the iron and steel industry, there were plenty of qualitative researches, but the quantitative research was almost none. So this study has the initiative and strong operability. The road map was divided into three stages:first of all, the promotion of new technologies, and increase efforts of scrap recycling. This stage was called the "technical stage". Then when there were enough steel scrap accumulation and enough electric furnaces were constructed, it will be the proper time to intensify efforts to promote short flow steelmaking, called "the EAF stage". The third step was to apply a variety of methods to realize low energy consumption, aiming at zero emission, said "zero emission stage".Secondly, the study makes the comparison research of three factors:the iron to steel ratio, technology promotion and waste gas recycling in the two aspects of energy saving and emission reduction. The impact of these three methods on the energy consumption and emissions of iron and steel enterprises is studied individually, but the specific extent of the impact and the quantitive relationship were not concerned. This study built itself on the perspective of system, which means using system dynamics approach to place the three to a whole. The results proved that this attempt was feasible and effective. Study found that reducing iron to steel ratio is most effective in energy saving and emission reduction, but taking the domestic storage of scrap into account, further strengthen technology promotion is the most feasible strategy at present.Thirdly, the method of this research was combination of two:carbon flow analysis and system dynamics, which has achieved good results. The carbon flow analysis and system dynamics were both operated from an overall point of view, which are suitable for complex, dynamic and nonlinear systems such as steel making system. This synthesis method can effectively grasp the core problem, avoid the interference factor, and get the aimed solution.Fourthly, the key factors of low carbon production in iron and steel enterprises were extracted based on energy flow analysis. First, the scoring system was based on the analysis of energy flow, which makes it more targeted and practical; second, because the steel industry is the backbone of the industrial system, so the researches about it were more mature. Therefore, in the process of locating the key factors, the results of the existing literature were brought in to improve the expert scoring system, making the follow-up study more credible.In a word, this research constructed the model of iron and steel production process with energy flow analysis and system dynamics modeling, and comprehensively analyzed the effects of three key factors:iron to steel ratio, technology promotion and the secondary energy recovery on energy consumption and carbon emissions. Then a road map of low carbon production was proposed and related policy recommendations were given.更多还原