烧结过程细微颗粒物排放特征与控制方法

EMISSION CHARACTERISTICS AND CONTROL METHODS OF FINE PARTICLES IN SINTERING PROCESS

针对钢铁行业对大气环境质量的影响问题,对烧结过程中微细颗粒的排放特征、粉尘成分、PM_(2.5)成因及形貌、化学组成等进行总结分析,并对目前采用较普遍的湿式静电除尘器(WESP)和电袋除尘器(HPC)除尘效果进行了对比。分析研究得出:烧结过程中PM_(2.5)细微颗粒包括一次来源和二次来源,一次来源是由烧结过程直接排放,二次来源是气态污染物经过物理或化学变化而生成二次污染粒子,主要为硫酸盐、硝酸盐等。通过对比WESP和HPC的经济性和适用性,发现HPC适用于烧结厂新建除尘项目和旧除尘器的改造项目,不受烟气湿度的影响,与WESP相比具有较大优势。

For the problem of atmospheric environmental pollution in iron and steel industry, the emission characteristics of fine particles, dust components, forming mechanism, morphology and chemical components of PM2 5 were analyzed during the sintering process. The dust removal efficiency was compared between widely used wet electrostatic precipitator（WESP） and hybrid particulate collector（HPC）. The results showed that the PM25 fine particles came from two sources, primary and secondary. Primary source was derived from the direct discharge in production process. Secondary source was a secondary particle pollutant that derived from gas pollutant altered physically and chemically, which mainly contained sulphate and nitrate. By means of comparison with economy and applicability between two types of precipitator, it showed that HPC was suitable for new project of dust removal in sintering plant and reconstruction project for old dust collector, and did not influenced by flue gas humidity, which had more advantages compared with WESP.