| 钢铁生产行业二英污染特征变化及其排放因子 |
| 摘要点击 5016 全文点击 570 投稿时间：2021-10-26 修订日期：2022-12-24 |
| 查看HTML全文
查看全文 查看/发表评论 下载PDF阅读器 |
| 中文关键词 钢铁生产行业 二英 污染水平 排放特征 排放因子 |
| 英文关键词 iron and steel industry PCDD/Fs pollution levels pollution characteristics emission factors |
|
| 中文摘要 |
| 对我国某省多家钢铁生产企业烧结工序和电炉工序排放烟气中二英（PCDD/Fs）污染水平、排放特征及其排放因子进行了初步研究.结果表明，烧结工序PCDD/Fs毒性当量浓度（以I-TEQ计，下同）为0.003~0.557 ng·m-3，均值为0.165 ng·m-3；电炉工序PCDD/Fs毒性当量浓度为0.006~0.057 ng·m-3，均值为0.025 ng·m-3.PCDD/Fs毒性当量浓度水平总体较低，较2005~2019年研究报道结果下降1~2个数量级.2005~2020年，钢铁生产行业排放PCDD/Fs毒性当量浓度水平先升高后降低，尤其是新的标准限值实施以及对烟尘等常规污染物进行超低排放控制后，呈现大幅下降.指纹谱图特征显示，所有烟气样品17种PCDD/Fs中最大浓度贡献单体为2，3，7，8-TCDF，与已有研究中以高氯代PCDFs和PCDDs为主不同，且低氯代PCDFs占比有所增加，表明PCDD/Fs生成主要来源有所变化.烧结工序和电炉工序PCDD/Fs同类物指纹分布特征相似，呈现典型的高温热过程特征，两个工序生产过程中PCDD/Fs的生成机制可能均为"从头合成".钢铁生产企业烧结工序PCDD/Fs废气排放因子（以I-TEQ计，下同）为0.003~0.5 μg·t-1，排放因子平均值为（0.18±0.22）μg·t-1；电炉工序PCDD/Fs废气排放因子为0.04~0.5 μg·t-1，排放因子平均值为（0.27±0.23）μg·t-1；低于UNEP于2013发布的"二英和呋喃排放识别和量化标准工具包"以及2004年我国二英排放清单中的排放因子，建议对我国钢铁生产行业PCDD/Fs排放状况开展调查，更新排放因子. |
| 英文摘要 |
| The pollution level, emission characteristics, and emission factors of PCDD/Fs from a number of steel plants were investigated in a particular province of China. The results showed that the concentration of PCDD/Fs was at a low level and decreased by 1-2 orders of magnitude compared with that in 2005-2019. In detail, the concentrations of PCDD/Fs ranged from 0.003-0.557 ng·m-3(I-TEQ), and the mean value was 0.165 ng·m-3 for the sintering process. Moreover, the concentrations of PCDD/Fs ranged from 0.006 to 0.057 ng·m-3, and the mean value was 0.025 ng·m-3 for the electric furnace process. In addition, the concentration of PCDD/Fs in the iron and steel industry from 2005 to 2020 increased first and then decreased, especially after the implementation of the new emission standard and the ultra-low emission control of conventional pollutants such as smoke, showing a significant decline. The results of fingerprint analysis showed that 2,3,7,8-TCDF was the largest congener contributing to the mass concentration, and lower chlorinated PCDFs were increased. This result differed from those of previous studies in which highly chlorinated PCDFs and PCDDs dominated, indicating that the generation source of PCDD/Fs had changed. The congener and isomer profiles of PCDD/Fs in flue gas from the sintering process were similar to those in the flue gas from the electric furnace process. Additionally, showing the characteristics of the typical high-temperature thermal process, the de novo synthesis may be the dominant mechanism of formation of PCDD/Fs in the sintering process and electric furnace process. The emission factor was 0.003-0.5 μg·t-1 (I-TEQ), and the average emission factor was (0.18±0.22) μg·t-1 for the sintering process. The emission factor was 0.04-0.5 μg·t-1, and the average emission factor was (0.27±0.23) μg·t-1 for the electric furnace process. These values were far lower than those of the standard toolkit for identification and quantification of dioxin and furan emissions released by UNEP in 2013 and the emission factors in the dioxin emission inventory of China in 2004. It is suggested that the emission factors of PCDD/Fs in the iron and steel industry of China should be studied and updated. |
|
|
|
