نوع مقاله : یادداشت فنی
نویسندگان
1 انستیتو آب و انرژی - دانشگاه صنعتی شریف
2 دانشکده مهندسی عمران- دانشگاه صنعتی شریف
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
Wind-induced particulate emissions from iron ore storage piles of a steel complex cause ambient air pollution, as well as conventional point sources. The dispersed particles enhance the ambient particulate pollution of the complex and adjacent urban areas; in addition, having economic detriment due to losing raw materials is a secondary concern. While most previously done research has been concentrated on point sources of particulate emissions, this study was begun to estimate the emission factor of wind-induced particles from the storage piles.Experiments were conducted to assess the impact of wind speed and humidity on particulate emission rates from iron ore storage piles. A wind generating system and specific iron ore, experimental piles (L:W:H of 30:11.5:5 cm) were constructed to evaluate emission rates at 4 different wind velocities (4.3, 5, 7 and 11 m s-1). Optical and electron microscopes were used for determining the size distribution of particles at various distances from the emission source. Moreover, the decrease in emission rate was evaluated by changing the percentage of pile surface water content at maximum speed. Finally, experimental results were compared with classic erosion equations and common parameters such as shearing velocity.Results indicated emission factors of 478, 1527, 2315 and 4409 g m$^{-2}$, for 4.3, 5, 7, 11 m s$^{-1}$ wind speeds, respectively. The pile surface water content variations indicated a decrease of 47\% to 77\% in wind-induced particulate emissions for pile surface water contents of 2 and 10\%, respectively. However, tthe presence of continuous differential pressure in natural winds for long distances, compared to the experimental conditions of thegenerated wind in this study, were attributed to the relatively shorter transported distance of the particles.
کلیدواژهها [English]
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