炼焦炉周边土壤、降尘和熄焦渣中水溶性离子的分布特征

为了明确炼焦炉周边土壤、降尘和熄焦渣中水溶性离子的分布特征，采集焦化厂厂区内土壤、降尘、熄焦渣及厂区外土壤样品，利用美国戴安公司ICS-90型离子色谱仪测定样品中SO₄2-、NO₃-、Cl-、F-、NH₄+、Na+、Ca2+、K+、Mg2+ 9种水溶性离子。结果表明:炼焦炉周边土壤、降尘和熄焦渣中总水溶性离子质量浓度分别为1.65，5.27，2.19 g/kg。炼焦炉周边土壤中SO₄2-和NH₄+的变异系数分别为84.22%和51.17%，说明炼焦炉周边土壤受到炼焦过程排放污染物的影响不同，且厂区内土壤更易受到炼焦过程的影响。燃烧室废气排放烟囱旁和熄焦塔南降尘中NO₃-/SO₄2-分别为0.46和0.03，说明炼焦炉周边降尘也受到炼焦过程排放污染物的影响。熄焦塔南降尘中总水溶性离子和SO₄2-的质量分数是燃烧室废气烟囱旁降尘的6.99，18.44倍，熄焦渣和熄焦塔南降尘水溶性离子分布特征基本相同，二者之间存在明显相关性。SO₄2-是炼焦炉周边土壤、降尘和熄焦渣中质量分数最高的水溶性离子，因此建议加强炼焦过程颗粒物和SO₂排放的控制。

DISTRIBUTION CHARACTERISTICS OF WATER-SOLUBLE IONS IN SOILS,DUST AND COKE QUENCHING SLAG AROUND THE COKE OVEN

In order to clarify the distribution characteristics of water-soluble ions in the soils, dust and coke quenching slag around the coke oven, the samples around the coke oven were collected. Ions (SO₄2-, NO₃-, Cl-, F-, NH₄+, Na+, Ca2+, K+, and Mg2+) in the samples were analyzed using ICS-90 ion chromatograph (Dionex, USA).The results showed that the mass fractions of water-soluble ions in the soils, dust and coke quenching slag around the coke oven were 1.65, 5.27, 2.19 g/kg, respectively. The variation coefficients of SO₄2- and NH₄+ in the soils around the coke oven were 84.22% and 51.17%, suggesting that the soils were affected differently by pollutants emitted during coking process. The soil inside the coking plant were more susceptible to pollutants emitted from coking process, than those in the soil outside the coking plant. The NO₃-/SO₄2- ratios in the dust near combustion chamber exhaust chimney and in south of quenching tower were 0.46 and 0.03, respectively, indicating that the dust around the coke oven was also affected by the pollutants emitted from coking process. The mass fractions of total water-soluble ions and SO₄2- in the dust in south of quenching tower were 6.99 times and 18.44 times those of the dust next to combustion chamber exhaust chimney, respectively. The distribution characteristic of water-soluble ions in coke quenching slag was almost the same as that in dust in south of quenching tower, and there was a significant correlation between coke quenching slag and dust in south of quenching tower. SO₄2- was a water-soluble ion with the highest mass fraction in the soils, dust and coke quenching slag around the coke oven. Therefore, it was suggested to strengthen the control of particulate matter and SO₂ emission in the coking process.