materials and methods. number of monitoring sites and area types overall egypt totalsinai upper...
Post on 22-Dec-2015
216 Views
Preview:
TRANSCRIPT
Materials and MethodsMaterials and Methods
Number of monitoring sites and Number of monitoring sites and area types overall Egyptarea types overall Egypt
Area typeCairoAlex.Delta and
CanalUpper Egypt
SinaiTotal
Industrial333211
Urban11349
Residential422210
Street/road33
Regional/backr.
1113
Mixed areas21216
Total148109142
Instruments and measurements techniques used in the air quality monitoring network
PollutantsSO2NO/NO2PM10COO3
Concentration Units
(µg/m3)(µg/m3)(µg/m3)(mg/m3)(µg/m3)
Measurement technique
Pulsed UV-Flourescens
Chemiluminescence
Tapered Filter element
oscillating mocrobalance
Gas Filter correlation (Infrared
Absorption)
UV- Photometric Absorption
Instrument typeThermo
Environmental (TEI) M 43 C
Thermo Environmental (TEI)
M 42 C
Beta gauge Ambient
particulate monitor
TEI M 48 CTEI M49 C
Air Quality Monitoring NetworkA full description of the selected monitoring sites
(8 sites) used in the study • Shoubra El Kheima
• Area description Highly industrial, very
polluted, several small smelters and
various industries.
• Local Sources Lead smelters to the west,
north and east of the school, within a few
hundred meters.
• Representativity Very polluted industrial
area.
• Data show the impact of industries on the
building.
• Paramters measuredSO2, NO2, TSP, PM10
Abbassyia site
• Description Regional residential area
normally up-wind from Cairo city
center, but down-wind from the
Shoubra industrial area and Shoubra
urban area.
• Local Sources: No immediate local
sources, but regionally exposed.
• Representativity: Regional urban
area.
• Paramters measuredSO2, NO2, O3 and
Meteorology Measurement
Qulaly site
• Area description: Urban center with
dense traffic on the street coming from
shoubra and crossing streets into Al
Qulaly and to Ramses Station.
• Local Sources: The area is expected to
be highly polluted from traffic in the
main railway station area of Cairo. There
are small industries north of the site and
the whole Shoubra area is located
upwind in prevailing wind direction.
• Representativity: urban central part of
Cairo.
• Paramters measuredSO2, NO2, PM10,
TSP, and VOC.Measurement
El Gomhoria site description • Description: Street canyon in
urban area with heavy traffic.• Local Sources: Mainly traffic in
the general area and around Ramses square (about 300m from the site). Heavy traffic on Gomhoryia street just under the sampler intake.
• Representativity: Representative for street canyons in central Cairo.
• Paramters measured SO2, NO2, CO, PM10
Fum El Khalig site description• Description: Urban center
roadside monitoring station with dense traffic on the streets on both sides of the site.
• Local Sources: The area is expected to be highly polluted from traffic
• Representativity: Representative for the urban central part of Cairo and specifically near two main roads.
• Paramters measured SO2, NO2, CO
Maadi Site description• Description: Residential • Local Sources: Mainly Traffic and general
activities of people.• Representativity: Typical for western Maadi area,
near street surrounded by tall trees (slightly more traffic impacted than inside residential Maadi).
• Paramters measured SO2, NO2
Tabbin Site description• Area description: Industrial,
polluted from several cement factories and others north of the site, and smelters and chemical industries to the south.
• Local Sources Smelters, steel and iron factories, coke factory within 1 Km to the south, cement factories in the sector north-west to north-east.
• Representativity: Very polluted industrial area.
• Data is showing the impact of industries on the building.
• Paramters measuredSO2, NO2, TSP, PM10 dustfall and meteorology Measurement.
10th of Ramadan site description• Area description: Some smaller industries 1-km to
the north (upwind). Some industries to the west, but the major industries park is located to the south and south east; 2-3 km away.
• Not expected to be a polluted area. • Representativity: Residential area.• Paramters measured: SO2, NO2 and PM10 and
dustfall.
10 Ramadan station
Dispersion Model Description POLAIR
• The POLAIR modeling has the fuctionality to simulate
the atmospheric dispersion of gaseous polluting
agents and fine particles from diverse sources. With
the help of mathematical equations,
• POLAIR can help study the impact of emissions in
zones subject to atmospheric pollution.
• The results are easily interpreted with graphical views
depicitng color graded graphs.
Input, output and validation of dispersion model
Plume’s superelevation models
Three models are availble to estimate the concentration
by dispersion modeling
• The U.S. Environmental protection Agency (EPA)’s
superelevation model;
• Holland’s superelevation model;
• Communauté Urbaine de Montréal’s (CUM) regulatory
superelevation model.
• For the majority of study case scenarios, it is highly
recommended to use the regulatory EPA model. It takes
into account each of the varaibles for the plume’s
superelevation and better represents reality.
Plume’s atmospheric dispersion model
Gaussian model and associated parametersThe Gaussian model is the most used in the world to study
dispersion phenomena. This model estimates the pollutants’s
concentration in spatial points while taking into account the
following factors: the emission’s characteristics, the receiving
environment and the meteorolgical conditions.
Interface and menus
Compound under studyPOLAIR model offers a database on physical, chemical and
toxicological properties. The avaiable information is as follows:
• Name of chemical compound;
• Chemical formula;
• Molecular weight;
• Terminal velocity (can be used at 0m/s as the majority of gases
have a density similar to air. This is not the case for particles and
heavy metals);
• Thershold of smell preception;
• Inferior limits for explosion and flammability;
• Toxcity threshold;
• Concentrations profile.
Types of simulation
• Simulation results can be shown in results in several types of data presentations. The types of simulation can be seen in the results are as follows:
• With maxima – First hourly maximum;– Second hourly maximum;– Mean concentration on 2h, 4h, 8h and 24
hours.
• Perecentages of threstholds;• Hourly arithmetic mean concentration.
Simulation with threshold overshoot
• The simulation with threshold overshoot indicate
in percentage, the proportions of calculated
values that have exceeded the set threshold of
concentration. In accordance to the receiving
point. The threshold was set according to the
maximum permissible values in indicated in the
Egyptain Environmental law no. 4/1994.
Passive and hand held samplers
• Passive samplers have been used
for Model verfication along different
distances (200m – 2000 m) for some
of the monitoring sites (Tabbin-
Maadi –Qualaly and Abassyia).
• Passive samplers is used for
surveillance of time integrated SO2
and NO2 concentration distributions.
• They have been analyzed in the
laboratory after exposure in the field
for typically one week.
Results and DiscussionResults and Discussion
POLAIR dispersion model performance results for SO2 concentrations prediction using national monitoring
stations network in Greater Cairo during 2004
Monitoring sites
No. of OBS.
Mean Calculated
(µg/m3)
Mean Observed (µg/m3)
Ratio of means
Calc/Obs
Mean error
(µg/m3)
Normalized mean error
%
Fractional error %
Correlation coefficient, r2
Shoubra875945.268.00.661.5050.450.730.96
Abassyia865522.226.60.830.1216.550.150.86
Qualaly875686.365.91.30.5830.926.800.87
Gomohria869841.534.11.20.2021.757.140.56
Maadi876441.733.31.250.7025.250.400.71
10th of Ramadan
87804.75.11.080.0317.859.100.73
Distribution of annual mean SO2 concentrations in µg/m3
calculated with POLAIR dispersion model using (2004) SO2
concentrations from the national monitoring network at Abassyia site
Distribution of SO2 concentrations over shooting (150 µg/m3
per 24 hours) calculated with POLAIR dispersion model using (2004) SO2 concentrations from the national
monitoring network at Abassyia site
Distribution of SO2 concentrations over shooting (150 µg/m3
per 24 hours) calculated with POLAIR dispersion model using (2004) SO2 concentrations from the national
monitoring network at Qualaly site
Annual mean SO2: observations versus predictions at some monitoring sites in Greater
Cairo during 2004
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
80.0
90.0
100.0
Maadi Gomohria Qulaly Abassyia Shoubra Elkemia 10th Ramadan
Monitoring sites
SO
2 co
nce
ntr
atio
n(µ
g/m
3)
Observed concentration(µg/m3)
Predicted concentration(µg/m3)
top related