PARTICULATE DISPERSION MODELING OF SALT HARVESTING ACTIVITIES FROM LAKE URMIA
Introduction: Drying of parts of Lake Urmia has exposed to salt domes in various areas of the lake. As such, the economic incentive for salt harvesting has been improved due to the easier access. Nonetheless, these operations have the potential of generating particulate air pollutants that can adversely impact immediate and distant agricultural and residential areas. Dispersion modeling is needed to evaluate the effect of various operational parameters on the generation and transport of these particulates.
Materials and methods: A mine with the capacity of 1250 tons /day in the area of Qobadlu and two other salt sites around lake Urmia were considered for modeling. Major activities that contribute to pollutant production include transport vehicles and wind erosion from storage salt piles. Wind erosion from the piles was evaluated under different scenarios using CFD approach. Using emission factors for other activities, topographic and climate data, Gaussian dispersion of particles was conducted using ADMS modelling system.
Results: The results showed that transportation of particles occurs towards the lake with negligible concentrations for distances within the 150 m radius; observed trend was a reduction from concentrations of around 100 μg / m3 at the site to 5 μg / m3 at the afore - mentioned distance. Layout optimization of storage piles and erection of barriers respectively resulted in up to 17 % and 44 % reduction in particulate generation from pile surfaces.
Conclusions: The results of this research have been used in the preparation of the environmental guidelines for salt harvesting in compliance with the lake Urmia restoration directives.
Shamsipour A, Najibzadeh F, Zarei Chaghabalki Z. The
numerical modeling and simulating of winds over Urmia
Lake basin. Natural geography research. Journal
of physical geography research quarterly. 2013; 45(1):
Nickfal A, Sehhat Kashani S, Karami S, Hossein Hamza
N. Evaluation of EURAD and WRF / chem numerical
models in forecasting of dust (case study February
. The 5th national conference on air pollution and
sound management. Iran clean air science association.
Pourasghar F, Hasan Alizadeh A, Akbarzadeh Y, Soltani
M. Investigating the distribution of salt particles into
the surrounding environment in the Urmia Lake. National
conference of air flow and pollution. 2012
Haji SA, Hosseini SM. Comparison of software models
for simulating particle distribution. First conference of
environmental engineering. University of Tehran, 2008
Cong XC, Yang SL, Cao SQ, Chen ZL, Dai MX, Peng
ST. Effect of aggregate stockpile configuration and layout
on dust emissions in an open yard. Applied mathematical
modeling. 2012; 36(11): 5482-5491.
US Environmental Protection Agency. AP - 42 section
2.2. Emission factor for unpaved roads. Washington
D.C: EPA; 2006
Department of environmental quality, state of Utah. Emission factors for paved and unpaved Haul roads.
Arizona department of environmental quality. Revised
PM10 state implementation plan for the salt river area.
Fariborzai Araghi F, Salari A. Principles and criteria of
load dimensions and weights. Tehran: ARG engineering
US Environmental Protection Agency. AP-42 Section
2.4. Emission factor for aggregate handling and storage
piles. Washington D.C: EPA; 2006
The salt institute of the United States. Salt storage
handbook, safe and sustainable salt storage. United
States: The salt institute; 2015.