铁路运输过程中煤粉尘遗洒对环境影响的初步评估与控制对策

煤炭的铁路运输是我国能源供给和调控的主要方式,但针对运输过程中煤粉尘遗洒对环境影响的相关研究较少。以大秦铁路为研究对象,对其在北京境内煤粉尘遗洒对大气、水、土的影响开展研究。结果表明:当有列车经过时,环境空气中可吸入颗粒物(PM₁₀)的浓度明显上升,并呈周期性波动,其中城区点位PM₁₀最高值为212μg/m3,隧道口点位PM₁₀最高值为3290μg/m3,运输过程中煤粉尘对周边空气质量的影响随着距离铁路的增加而急速衰减;煤粉尘的传输沉降导致监测附近点河水中的SS明显增加;此外,受煤粉尘污染,监测点附近表层土土壤样品呈弱酸性,且Cr、Cd、Pb等重金属含量均高于背景值。根据初步估算,大秦铁路在运输过程中煤粉尘排放总量为3441.46 t/a,在北京境内煤粉尘排放量为579.73 t/a。结合各种工艺的优缺点和适用性,建议采取分段龙门吊式喷淋技术,并针对喷淋抑尘剂法提出改进建议,加强铁路运输段煤粉尘治理,减少污染排放。

PRIMARY STUDY ON ENVIRONMENTAL IMPACT AND CONTROL MEASURES OF FUGITIVE COAL DUST DURING RAILWAY TRANSPORTATION

The railway transportation of coal is the main way of energy supply and regulation in China, but the related researches on the impact of fugitive coal dust during railway transportation on environment are rare. This paper studied the impact of coal dust spillage on the atmosphere, water and soil in Beijing areas during railway transportation. The results showed that the concentration of PM₁₀ in the ambient air increased obviously and fluctuated periodically. The highest values of PM₁₀ at urban site and tunnel site were 212, 3290 μg/m3, respectively. And the influence on ambient air decreased rapidly as a function of distance. The transport and settlement of coal dust led to the increase of suspended matters in river near the monitoring site. In addition, the surface soil samples appeared weakly acidic, and the contents of Cr, CD, Pb and other heavy metals were much higher than those of the background sites. According to the primary estimation, the emission amounts of fugitive coal dust was about 3441.46 tons per year, and annual emission in Beijing areas was about 579.73 tons. It was suggested that the gantry crane spraying technology should be adopted, and dust suppressants should be improved, with the aim to strengthen the fugitive coal dust control in the railway transportation.