基于流程的钢铁生产过程环境负荷分析与优化

Analysis and Optimization of Environmental Impact on Process-Based Steel Production

叙述了生命周期评价方法在钢铁工业中应用现状和发展前景,并对钢铁生产传统工艺流程和钢铁生产新工艺流程和新技术的环境负荷进行分析和评价。基于钢铁生产新工艺流程和新技术的不断应用,对熔融还原炼铁和薄板坯连铸连轧生产工艺和流程的环境负荷进行了评价,与传统高炉流程相比,熔融还原炼铁废气污染物和废水污染物减排效果十分明显;与传统热连轧工艺相比,薄板坯连铸连轧工艺吨材煤气消耗降低2/3,吨材烟粉尘排放降低约27%。此外,针对我国钢铁生产矿物资源和能源消耗过大、环境污染问题十分突出的现状,指出通过改进原料和能源结构,加强环境排放控制和管理,有利于较大幅度地减少污染物的发生量和排放量。最后结合钢铁企业发展循环经济的实例,提出用生命周期评价方法对实施循环经济前后的环境负荷和循环经济发展程度进行分析研究。结果表明,钢铁企业采用新工艺流程和新技术,尤其是建设循环经济型企业,有利于从根本上降低钢铁生产过程环境负荷。

In this paper, the status of the application and development prospects of life cycle assessment method in the steel industry was described. Moreover, the environmental impacts of traditional steel production process and the new processes and technologies, were also analyzed and evaluated. Based on the application of new process and technology to the steel industry, the environmental impacts of smelting reduction iron making process and thin slab continuous rolling process were evaluated in the paper. Compared with the traditional blast furnace process, the reduction effect of waste gas and waste water pollutants emission for smelting reduction iron making process was very obvious. Even compared with con- ventional hot strip rolling process, the fuel consumption of thin slab continuous rolling process was reduced 2/3 and smoke dust emission reduced 27%. Since the steel industry consumes large amounts of mineral resources and energy, to cause en- vironmental pollution problems becomes very prominent, this paper pointed out that, by improving the consumption struc- ture of raw materials and energy, strengthening environmental emission control and management, it could be greatly re- duced for the amount of generation and emission of pollutants. Taking examples of the circular economy development in some steel companies, this paper thoroughly calculated and analyzed the environmental impacts of before and after the im- plementation of circulation economy, and its development level by using life cycle assessment method. The results show that the new technology and new steel production process especially in the construction of circular economy enterprises, will help to reduce the environmental impacts of steel production process fundamentally.