中国典型钢铁联合企业的碳足迹分析

 明确了碳足迹概念，综合森林面积对碳排放的缓解作用，并基于物流分析和投入产出的耦合法建立MFA-IO模型分析钢铁企业的碳足迹。以中国5个典型钢铁企业为实例，研究钢铁企业的吨钢产品的碳足迹及其影响因素。结果表明：从钢铁生产工序分析，炼铁工序的碳足迹最大，且消耗的能源中含有大量的焦炭、煤。其次是焦化、烧结工序。从气体种类分析，钢铁生产中碳足迹的主要贡献者是CO2，在5个案例分析中，CO2的贡献值均占到了70%以上。5个典型企业吨钢产品的碳足迹平均为0.325 hm2/t。其中，企业D的吨钢产品碳足迹最高，高达0.353 hm2/t，而企业E的最小，为0.303 hm2/t。这主要是由地域差异、企业周围能源分布差异、生产设备与技术差异等综合因素导致的。总体分析，5个典型企业总碳足迹合计为1 989.58万hm2，超过5省森林面积的总和。表明其总CO2排放量就已超出森林吸收净化的能力，总温室气体排放量更是超出森林净化能力，即碳足迹的承载呈严重赤字。因此，研究如何减少中国钢铁工业吨钢碳足迹是十分必要和紧迫的。

Carbon footprint analysis of typical chinese iron and steel enterprises

By definition of ecological footprint，carbon footprint is expressed in forest area. And the MFA-IO model was established to analyze carbon footprint in the whole process of iron and steel enterprise. Carbon footprint of per ton steel，was calculated in five typical iron and steel enterprises. Results show that carbon footprint of iron-making is largest accounting for 70% in iron and steel enterprises. And coke and coal are large consumption in iron-making，coking and sintering process are less than iron-making. Analyzing the type of gas，carbon dioxide is a major contributor of carbon footprint in the whole production process. In the five cases，the contribution of CO2 values was accounted for about 70%. And the average carbon footprint of per ton steel products was 0.325 hm2/t. Among them，the Nanjing Steel carbon footprint of per ton steel products was up to 0.353 hm2/t，while Baosteel Branch’s smallest was only 0.303 hm2/t. The differences are mainly due to geographical differences，the distribution of energy around the enterprise and production equipment and technology. For overall analysis，the total carbon footprint was 19 895 800 hm2，the sum of the five provinces of forest area. This research shows that for only these five cases of iron and steel enterprises，the total GHG exceeded the purification capacity of the forest in the five provinces. Therefore，the study of China’s steel industry to reduce the carbon footprint is very necessary and urgent.