烧结工艺颗粒物中水溶性离子排放特性分析

采用荷电低压颗粒物撞击器（ELPI）对两段烧结工艺经除尘、脱硫后排放的颗粒物进行采样，分析颗粒物的粒数和质量浓度以及颗粒物中所含水溶性离子的粒径分布特征.结果表明，烧结工艺经除尘、脱硫后颗粒物的粒数浓度在10⁵～10⁷cm^-3，粒径小于0.1μm的颗粒物占总粒数浓度的67%～77%.颗粒物质量浓度呈双峰分布，烧结1分别在0.61μm和1.62μm处出现峰值，烧结2分别在0.37μm和1.62μm处出现峰值；对不同粒径段颗粒物中的水溶性离子进行分析后表明，烧结1排放的PM₁中含量最高的是NH₄⁺和Ca²⁺，分别为15.26%和14.84%；PM_>1中含量最高的是SO₄^2-，为33.52%.烧结2排放的PM₁中含量最高的是Cl^-，为28.12%；PM_>1中含量最高的是SO₄^2-，为29.21%.SO₄^2-在烧结1中主要集中在6.89～10.23μm这一粗粒径段中，占60%左右，而在烧结2中主要集中在粒径小于2.5μm的细粒径段颗粒物中，占81%左右.Cl^-在烧结1不同粒径段颗粒物中含量较低且分布较均匀，而在烧结2中Cl^-在0.13～0.24μm粒径段颗粒物中出现峰值且含量较高达45%左右.

Emission characteristics of water-soluble ions in the particulate matters from sintering process

Electrical low pressure impactor (ELPI) was used to analyze the particulate matters size, mass concentration distribution and ions from two sintering processes after dust removal and desulfurization. Results showed that the grain number concentration of the particulate matters from the sintering process after dust removal and desulfurization was in the range of 10⁵~10⁷cm^-3, and 67%~77% particulate matters' particle sizes were mainly below 0.1μm. The mass concentration distribution showed double peaks. Two peaks respectively existed at 0.61μm and 1.62μm of particle size in No.1sintering process, while two peaks respectively existed at 0.37μm and 1.62μm of particle size in No.2 sintering process. Chemical composition analysis indicated that the highest content of water-soluble ions in PM₁ from No.1 sintering process were NH₄⁺ and Ca²⁺, which was 15.26% and 14.84%, respectively. The highest content of water-soluble ion in PM_>1 from No.1 sintering process was SO₄^2-, which was 33.52%. The highest content of water-soluble ions in PM₁ and PM_>1 from No.2 sintering process were Cl^- and SO₄^2-, which was 28.12% and 29.21%, respectively. 60% of SO₄^2- concentrated in the particulate matters of 6.89~10.23μm particle size in No.1sintering process, and 81% of SO₄^2- concentrated in the particulate matters with the particle size below 2.5μm in No.2 sintering process. The content of Cl^- in the particulate matters of different particle sizes distributes uniformly in No.1sintering process, and 45% of Cl^- concentrated in the particulate matters of 0.13~0.24μm particle size for a peak in No.2 sintering process.