中国钢铁行业重点工序烟气超低排放技术进展

Progress of ultra-low emission technology for key processes of iron and steel industry in China

钢铁行业已成为中国大气污染防治重点行业,目前中国已提出钢铁行业烧结、球团等工序超低排放限值。总结了烧结(球团)、焦炉、高炉、转炉等多个工序高效净化技术路线,集成了源头减排、过程控制和末端治理的多污染物超低排放技术体系,包括'烟气循环技术'、'半干法脱硫耦合中低温SCR脱硝技术'、'活性炭法一体化技术'、'臭氧氧化硫硝协同吸收技术'、'高炉炉料结构优化的硫硝源头减排技术'、'转炉二次烟气预荷电袋滤器除尘技术'等关键技术,上述技术在中国部分钢铁企业均有应用实践。最后提出了生产技术绿色化、污染计量合理化、加强非常规污染物管控、重视钢铁行业碳排放的发展建议。

The iron and steel industry has been the key field of the air pollution control in China,and the ultra-low emission standard for the sintering and pelletizing of iron and steel industry has been proposed.The purification technologies for multiple processes such as sintering(pellet),coking,blast furnace,and converter were summarized.The multi-pollutants ultra-low emission technologies are based on the source reduction,process control,and end-of-pipe treatment,including the flue gas circulating,semi-dry desulfuration with medium and low temperature SCR denitration,activated carbon method,ozone oxidation with SO2 and NOx synergistic absorption,optimization of raw material structure of blast furnace for source reduction of SO2 and NOx,pre-charging bag-type dust collecting technology for the second flue gas of the converter.The above technologies have been applied in the iron and steel plants in China.Eventually,the advices such as greenization of production technology,rationalization of the pollutant measurement,strengthening the unconventional pollutants control,attaching greater importance to carbon emissions from the iron and steel industry are proposed.