The fourth Scientific Conference SEMREGG 2018 158 THE USE OF AERMOD MODEL FOR SIMULATING AIR POLLUTANTS DISPERSION IN AMATA INDUSTRIAL PARK OF DONG NAI PROVINCE Le Hoang Phong 1 , Nguyen Thanh Ngan 1[.]
Trang 1THE USE OF AERMOD MODEL FOR SIMULATING AIR
POLLUTANTS DISPERSION IN AMATA INDUSTRIAL PARK OF
DONG NAI PROVINCE
Le Hoang Phong 1 , Nguyen Thanh Ngan 1
1
Faculty of Environment, Ho Chi Minh City University of Natural Resources and Environment,
236B Le Van Sy Street, Ward 1, Tan Binh district, Ho Chi Minh City
Email: ntngan_hcmunre@yahoo.com
ABSTRACT
AMATA Industrial Park is one of important industrial parks of Dong Nai Province This industrial park is located at Long Binh ward, suburban of Bien Hoa city In recent years, AMATA industrial park has become a “hot spot” for air pollution in Dong Nai province This research is conducted to simulate air pollutants dispersion from AMATA Industrial Park to neighboring areas
in Bien Hoa city The atmospheric dispersion model used in this research is AERMOD model of U.S EPA and the simulation periods are in 2015 and 2016 Three pollutants chosen to simulate are Carbon Monoxide (CO), Sulfur Dioxide (SO2) and Total Suspended Particles (TSP) This research has pointed out the spatial distribution of three main air pollutants in AMATA Industrial Park, provide the basis for setting out the reasonable solutions to reduce air pollution in this area
Keywords: AERMOD model; atmospheric dispersion model; air pollution; AMATA Industrial
Park; Dong Nai province
1 INTRODUCTION
AMATA Industrial Park is a large-scale high-tech industrial park of the Southern Key Economic Zone (SKEZ) of Vietnam It is located on the Hanoi Highway in Bien Hoa city, which is the economic and social centre of Dong Nai province According to information provided by Dong Nai Department of Environmental Protection, the total area of this industrial park is 513.01 ha with over 100 operating companies (139 operating companies in 2016) work in 15 different main sectors [1] In recent years, due to production activities, AMATA Industrial Park has caused high-level air pollution to Bien Hoa city This industrial park is considered one of the “hot spots” for air pollution
in Dong Nai province Because of that reason, this research is conducted to simulate air pollutants dispersion from AMATA Industrial Park to neighboring areas in Bien Hoa city, provide the scientific basis for managers to set out the reasonable solutions to reduce air pollution in this area
In this research, three pollutants chosen to simulate air pollution dispersion are Carbon Monoxide (CO), Sulfur Dioxide (SO2) and Total Suspended Particles (TSP) The simulation periods are carried out in two years 2015 and 2016 The atmospheric dispersion model chosen to simulate air pollutants dispersion for AMATA Industrial Park is AERMOD model The AERMOD model is
an atmospheric dispersion model that was developed by U.S EPA [2] This model is used popular
in many places of the world for assessing air pollution from industrial sources [3-10] In stable conditions, the concentration expression of AERMOD model has the form of Gaussian distribution,
is represented as follows [11]:
Trang 2* +
√ ̃ ∑ [ (
( )
( ( )
Where Q is the emission rate of the pollutant, ũ is wind speed at stack height, σzs is the total vertical dispersion in the stable boundary layer, hes is the plume height (stack height plus the plume rise) and zieff is the effective mechanical mixed layer height [11]
2 METHODS AND DATA 2.1 Methods
The research process is divided into the six following phases: (1) collecting related data, (2) processing to model input data, (3) simulating air pollutants dispersion, (4) creating air pollutants distribution maps, (5) comparing with ambient air quality standard, (6) evaluating results and drawing conclusions The main tasks of the research are done in Phase (3) This is a very important phase that decide the accuracy of the results obtained The Figure 1 depicts the detailed research process diagram
Figure 1 Detailed research process diagram
Trang 32.2 Data
To carry out this research, the authors use five types of data: (1) administrative boundary data, (2) terrain elevation data, (3) meteorological data, (4) industrial sources data, (5) discrete receptors data The administrative boundary data of AMATA Industrial Park include five layers: boundary line, companies, roads, vegetation areas and water bodies Besides, the authors also use Google Map data to support to create the base map The terrain elevation data are DEM from the SRTM mission
at 90 m spatial resolution (3 arc second) The SRTM DEM of the study area are reprocessed to become the terrain input data for the AERMOD model with AERMAP module The administrative boundary map and terrain elevation map of AMATA Industrial Park are shown in Figure 2
(a) Administrative boundary map (b) Terrain elevation map
Figure 2 The administrative boundary and terrain elevation map of AMATA Industrial Park
The meteorological data are collected from the NOAA's National Climatic Data Center (NCDC) website These data are reprocessed to become the input data for the AERMOD model with AERMET module The Figure 3 represents the wind rose plots of the study area in two years
2015 and 2016 These wind rose plots are built by the WRPLOT View software of the Lakes Environmental Company
(a) First quarter 2015 (b) Second quarter 2015(c) Third quarter 2015(d) Fourth quarter 2015
(e) First quarter 2016 (f) Second quarter 2016(g) Third quarter 2016(h) Fourth quarter 2016
Figure 3 Wind rose plots of the study area in two years 2015 and 2016
Trang 4The industrial sources data are the measurements of 31 point sources from 26 companies surveyed in 2015 These measurements are the basis for calculating the emission rates of selected pollutants (CO, SO2 and TSP), an important factor affecting the accuracy of the results obtained The discrete receptors data are the coordinates and altitudes of 19 sensitive locations in the vicinity
of the AMATA Industrial Park This information is collected by Garmin GPSMAP 64st Receiver The location map of 31 point sources at AMATA Industrial Park is demonstrated in Figure 4
Figure 4 The location map of 31 point sources at AMATA Industrial Park
3 RESULTS AND DISCUSSION 3.1 Calculating the emission rates of selected pollutants
The first step of the simulating air pollutants dispersion process is calculating the emission rates of three selected pollutants: CO, SO2 and TSP The emission rates of 31 point sources in AMATA Industrial Park are estimated based on three types of information: the type of fuel used (Coal, DO, FO, Gas), the amount of fuel used (ton/h), and the performance of the machinery system (%) This information is collected by interview method with environmental staff of 26 companies Each type of the fuels used has a specific emission factor as defined in the technical documentation
of WHO in 1993 “Assessment of sources of air, water, and land pollution: a guide to rapid source inventory techniques and their use in formulating environmental control strategies” [12] The emission rates of selected pollutants are estimated by Microsoft Excel software The characteristics and emission rates of 31 point sources in AMATA Industrial Park are shown in Table 1
Table 1 The characteristics and emission rates of 31 point sources in AMATA Industrial Park
ID
Point
Source
Name
Fuel
Temperature (oK)
(ton/h)
Height (m)
Diameter
Trang 5ID
Point
Source
Name
Fuel
Temperature (oK)
(ton/h)
Height (m)
Diameter
3.2 Simulating air pollutants dispersion and creating air pollutants distribution maps
After calculating the emission rates of selected pollutants, the authors conduct to simulate air pollutants dispersion from AMATA Industrial Park to neighboring areas in Bien Hoa city with AERMOD View software The modeling domain extends from 696,722 m to 716,722 m East and 1,200,180 m to 1,220,180 m North (projection UTM Zone 48N WGS84) The length and width of the modeling domain are both 20 km (the area is 400 km2) The modeling domain has 400 grid cells with 31 point sources and 19 discrete receptors inside The Figure 5 depicts the modeling domain and the location of 19 discrete receptors in the study area
Trang 6(a) Modeling domain (b) Location of 19 discrete receptors
Figure 5 The modeling domain and the location of 19 discrete receptors
The simulation periods of the AERMOD model are in two years 2015 and 2016 These periods are chosen because these are times when the companies in AMATA Industrial Park operated at very high efficiency and emitted a large amount of pollutants into the air The results of simulating selected pollutants dispersion in 2015 and 2016 are shown in Figure 6 and Figure 7 respectively
Figure 6 The results of simulating CO, SO2 and TSP dispersion in 2015
The concentration plots in Figure 6 and Figure 7 indicated the maximum values of three selected pollutants in the study area as follows:
- CO: 239.0 µg/m3 in 2015 (at the distance of 5,400 m), 225.0 µg/m3 in 2016 (at the distance
of 3,400 m)
- SO2: 255.0 µg/m3 in 2015 (at the distance of 4,800 m), 251.0 µg/m3 in 2016 (at the distance
of 4,400 m)
- TSP: 95.1 µg/m3 in 2015 (at the distance of 2,900 m), 89.7 µg/m3 in 2016 (at the distance of 4,800 m)
Trang 7(a) CO (b) SO2 (c) TSP
Figure 7 The results of simulating CO, SO2 and TSP dispersion in 2016
The distribution maps in Figure 6 and Figure 7 shown the spatial distribution of the highest 1-hour concentrations of three selected pollutants in the study area The CO and TSP from point sources tend to spread in the northeast and southwest directions, while SO2 from point sources tends to spread in the north and south directions The two regions that usually had high concentration of selected pollutants in the study area are the Quarter 7 of Long Binh Ward and the Quarter 8A of Tan Bien Ward
3.3 The concentration values of selected pollutants at 19 discrete receptors
The results of simulating air pollutants dispersion process are also used to extract the concentration values of selected pollutants at 19 discrete receptors in the modeling domain These discrete receptors represent for 19 sensitive locations that have significant importance in environment and health aspects at the study area The concentration values of selected pollutants at
19 discrete receptors in 2015 and 2016 are shown in Table 2
Table 2 The concentration values of selected pollutants at 19 discrete receptors in 2015 and 2016
ID Receptor Name Highest concentration in 2015 (µg/m
3 ) Highest concentration in 2016 (µg/m3)