The assessment of pollutants in a gas flaring region is presented and the study area is Ogba/Egbema/Ndonni local Government area in Rivers State. The method adopted involves establishing points close to flaring locations and carrying out a daily observation of pollutant concentrations and meteorological parameters. Five locations were established and these were located in Obite, Idu,Ebocha and Mgbede villages. A weather station was mounted in Obite village and the pollutants measured were NO2, SO2, CO, O3, PM2.5 and PM10. The meteorological parameters recorded were solar radiation, wind speed and direction, temperature and humidity.

1. http://www.iaeme.com/IJCIET/index.asp 7 editor@iaeme.com
International Journal of Civil Engineering and Technology (IJCIET)
Volume 7, Issue 3, May–June 2016, pp. 07–17, Article ID: IJCIET_07_03_002
Available online at
http://www.iaeme.com/IJCIET/issues.asp?JType=IJCIET&VType=7&IType=3
Journal Impact Factor (2016): 9.7820 (Calculated by GISI) www.jifactor.com
ISSN Print: 0976-6308 and ISSN Online: 0976-6316
© IAEME Publication
ASSESSMENT OF STANDARD
POLLUTANTS IN A GAS FLARING
REGION: A CASE OF
OGBA/EGBEMA/NDONI LOCAL
GOVERNMENT AREA IN RIVERS STATE
OF NIGERIA
Ify L. Nwaogazie
Department of Civil and Environmental Engineering,
University of Port Harcourt, Rivers State, Nigeria
Abali Happy Wilson
Centre for Occupational Health,
Safety & Environment, Institute of Petroleum Studies,
University of Port Harcourt, Nigeria
Terry Henshaw
Africa Centre of Excellence,
University of Port Harcourt, Rivers State, Nigeria
ABSTRACT
The assessment of pollutants in a gas flaring region is presented and the
study area is Ogba/Egbema/Ndonni local Government area in Rivers State.
The method adopted involves establishing points close to flaring locations and
carrying out a daily observation of pollutant concentrations and
meteorological parameters. Five locations were established and these were
located in Obite, Idu,Ebocha and Mgbede villages. A weather station was
mounted in Obite village and the pollutants measured were NO2, SO2, CO, O3,
PM2.5 and PM10. The meteorological parameters recorded were solar
radiation, wind speed and direction, temperature and humidity. Results show
very high pollutant concentrations ofNO2, O3,PM2.5 and PM10 that surpasses
the regulatory limits as stipulated by World Health Organization (WHO) and
Federal ministry of Environment in Nigeria (FMEnv).NO2 showed maximum
mean concentration of 31.60mg/m3
at Obite village as against WHO limit of
2mg/m3
and FMEnv limit of 5mg/m3
.O3 showed maximum mean concentration
of 0.34mg/m3
at Obite village asagainst WHO limit of 1mg/m3
. PM2.5 showed a
maximum mean concentration of 26.7µg/m3
at Mgbede village as against

2. Ify L. Nwaogazie, Abali Happy Wilson and Terry Henshaw
http://www.iaeme.com/IJCIET/index.asp 8 editor@iaeme.com
WHO limit of 25µg/m3
and FMEnv limit of 15µg/m3
. PM10 showed maximum
mean concentration of 78.82µg/m3
at Idu (observation point 1) as against
WHO and FMEnv limit of 50µg/m3
. Meteorological observations showed
strong trends between pollutant reduction with temperature increment. Wind
speed and solar radiation were noted to be very significant meteorological
parameter as far as pollutant dispersion is involved. From this work we
recommend that the Government initiates and monitors a zero flaring policy
as these flaring activities impose negatively on the environment.
Cite this Article: Ify L. Nwaogazie, Abali Happy Wilson and Terry Henshaw.
Assessment of Standard Pollutants In A Gas Flaring Region: A Case of
Ogba/Egbema/Ndoni Local Government Area In Rivers State of Nigeria,
International Journal of Civil Engineering and Technology, 7(3), 2016, pp.
07–17.
http://www.iaeme.com/IJCIET/issues.asp?JType=IJCIET&VType=7&IType=3
INTRODUCTION
The essence of measuring air pollutants has been to check the impact of different
human activities on the environment. The atmosphere is very sensitive and composes
of 78% Nitrogen, 21% Oxygen and 0.9% Argon. Other gases such as carbon oxide,
nitrous oxide, methane, and ozone are trace gases that account for a tenth of one
percent of the atmosphere (Climate, 2016). Any composition in exceedence of the
above stated, then the atmosphere is regarded as polluted and its major impact is on
plants and animals. The main driver of air pollutants is the atmosphere and so
understanding its composition and other complexities enables us to understand
pollutant movement (Nwanya, 2011). The failure to understand air pollutant
movement in the atmosphere due to lack of metrological tools was made known by
Allen et at.(1975).
There are over 13 flares from Total Exploration Producing Company (Total E &
P), Nigeria Agip Oil Company (NAOC) and Shell Petroleum Development Company
(SPDC) in the local government area which has an approximate population of
335,000 people. The flares are used by these companies to burn natural gas produced
from oil processing plants/facilities. At Obagi community, there is a crude oil
processing centre for Total E & P. At Ebocha there is another oil processing centre for
NAOC. There is a flow station at Egbema and another at Idu owned by NAOC. There
are two gas processing facilities at Obite owned by Total E & P and Obrikom/Obiafu
owned by NAOC.
Given the level of industrialization by oil activities alone, air pollution from
flaring is of great concern. This has been continuously for nearly 50 years. The
accumulated effect on humans, plants, properties and other animalscan only be
imagined (Dung et al., 2008; Obia et al., 2011; Lawanson et al., 2008; Nkwocha and
Pat-Mbano, 2010; Ologunorisa, 2001). It has long been expected of government to
initiate policies that will reduce the impact of this activities that exert much visible
negativity to the environment (Onyekonwu, 2008).
Some of the works regarding air pollutant monitoring in Rivers state can be seen in
Zagha and Nwaogazie (2015); Henshaw et al.(2016); Nwanya (2011); and Christen
(2004).

3. Assessment of Standard Pollutants In A Gas Flaring Region: A Case of Ogba/Egbema/Ndoni
Local Government Area In Rivers State of Nigeria
http://www.iaeme.com/IJCIET/index.asp 9 editor@iaeme.com
MATERIALS AND METHODS
Study Area
Ogba/Egbema/Ndoni Local Government Area is one of the 23 local government areas
of Rivers State of Nigeria. It lies on Latitude 5.34167N and Longitude 6.65556 E. The
area is one of the highest flaring region, having a very high concentration of flaring
activities in the Niger Delta region of Nigeria (Anejionu et al.,2013).
The Ogba–Egbema–Ndoni Local Government Area is inhabited by the three tribes
namely: Ogba, Egbema and Ndoni people all sub-groups of the Igbo people. The
Ndonis are a pure stock of Ndokwa people of Delta State. They are great farmers and
fishermen with a rich cultural history. Figure 1 shows the map of Niger delta with the
study area represented as a white triangle. Figure 2 shows the observation sites and
the flaring locations in the study area. Tables 1 and 2 show coordinates of observation
sites and flaring points.
Figure 1 Map of Niger Delta of Nigeria showing Ogba/Egbema/NdoniLocal government area
Figure 2 Positions of observation points and flaring points in Ogba/Ndoni/Egbema LGA
Study
Area

4. Ify L. Nwaogazie, Abali Happy Wilson and Terry Henshaw
http://www.iaeme.com/IJCIET/index.asp 10 editor@iaeme.com
Table 1 Coordinates of observation points
S/N
POINT OF
READING
CO-ORDINATES
NORTHING EASTING
1 Obite 5°14'23.67"N 6°39'25.08"E
2 Idu location 1 5°15'28.82"N 6°35'42.14"E
3 Idu location 2 5°14'53.22"N 6°35'39.30"E
4 Ebocha 5°28'40.52"N 6°44'24.52"E
5 Mgbede 5°29'55.15"N 6°43'22.53"E
Table 2 Coordinates of flaring points
S/N FACILITY
CO-ORDINATES
NORTHING EASTING
1 Obirikom gas plant (OB-OB) 5°23'24.42"N 6°40'3.78"E
2 Obite gas plant 5°14'27.66"N 6°39'25.08"E
3 Obagi gas flow station 5°14'4.38"N 6°37'40.68"E
4 Idu flow station 5°14'33.00"N 6°36'5.22"E
5 Ebocha oil Centre 5°27'38.04"N 6°41'56.64"E
Equipment used
The equipment used for this work are as listed:
 Davis Due weather station to measure some weather parameters (mounted 10m high);
 Garmin model 64s GPRS to identify location of study;
 TES solar radiation monitor - hourly solar radiation levels;
 An Aeroset 531s Particulate matter monitor - hourly measurement of particulates;
 An Aeroqual 731 gas monitor – hourly pollutant levels monitoring; and
 Gas sensors (NO2, SO2, Ozone and CO) .
Procedure
Five observation sites were established, one in Obite, two in Idu, one in Mgbede and
one in Ebocha village. The observation point in Obite was behind the Obite gas plant,
that of Idu location-1 and location-2 were close to Obagi flow stations and the
Mgbede and Ebocha locations were close to Ebocha oil center and Obrikom gas plant.
The weather station was mounted at Obite location and the gas/ particulate monitors
were mounted on different sites at observation periods. Readings were taken from
6am to 7pm for all locations. Obite observations were carried out on October 10,
2015. Mgbede and Ebocha locations were observed on October 11, and Idu locations
1 and 2 observations were carried out on October 12, 2015.
RESULTS AND DISCUSSION
Results
From the three day observations in Ogba/Ndoni/Egbema LGA, a sample of the results
is presented for Obite village as Table 5 and others are presented as charts indicating
mean, minimum and maximum concentrations obtained from observations (See
Figures 3 – 7).

5. Assessment of Standard Pollutants In A Gas Flaring Region: A Case of Ogba/Egbema/Ndoni
Local Government Area In Rivers State of Nigeria
http://www.iaeme.com/IJCIET/index.asp 11 editor@iaeme.com
Figure 3Minimum/Maximum and Mean concentration of Pollutants at O
Figure 4 Minimum/maximum and mean pollutants concentrations in Ebocha
Figure 5 Minimum/maximum and mean pollutants concentrations in Mgbede
0 5 10 15 20 25 30 35 40
SO2
NO2
CO
O3
PM2.5
PM10
CONCENTRATION LEVELS
POLLUTANTS
MINIMUM/MAXIMUM AND MEAN POLLUTANTS CONCENTRAION
FOR OBITE
MEAN
MAXIMUM
MINIMUM

6. Ify L. Nwaogazie, Abali Happy Wilson and Terry Henshaw
http://www.iaeme.com/IJCIET/index.asp 12 editor@iaeme.com
Figure 6 Minimum/maximum and mean pollutants concentrations in Idu-location 1
Figure 7 pollutant minimum, maximum and mean levels
Table 5 Pollutants concentration for OBITE observation location
Time
AIR POLLUTANT
CONCENTRATION (Mg/M3
)
PARTICLATE POLLUTANT
CONCENTRATION
(Μg/M3
)
TEMPERATU
RE/HUMIDIT
Y
AT GROUND
LEVEL
TEMPERATURE/
HUMIDITY
AT 10 METER
HEIGHT
SOLAR
RADIATI
ON
CLOU
D
COVE
R
TIME SO2 NO2 CO O3 PM1 PM2.5 PM4 PM7 PM10 TSP 0
C % 0
C % ( W/m2
)
(OKTA
)
6:00 0.31 34.0 0 0.1 12.6 14.2 18 25.2 25.3 28.3 25 80 24.3 85 0 8
9:00 0.11 33.74 0 0.16 10.2 11.4 14.45 20.23 20.3 22.7 28 77 25.4 91 1049 4
12:00 0.0 33.22 0 0.16 8.2 9.16 11.62 16.26 16.32 18.25 32 64 29.8 76 1033 2
14:00 0.0 33.44 11.3 0.22 7.4 8.27 10.48 14.67 14.73 16.47 34 53 31.3 65 740 6
15:00 0.0 32.46 28.6 0.52 6.2 6.93 8.78 12.29 12.34 13.80 37 51.4 31.8 65 560 1
16:00 0.45 33.44 32.7 0.64 7.8 8.72 11.05 15.46 15.52 15.52 36 48 31.2 71 420 4
17:00 0.0 31.58 13.9 0.54 9.6 12 16.2 20.5 22.7 27.7 29 76 29.1 81 220 4
18:00 0.0 32.55 7.8 0.4 8.0 10.2 13.5 17.6 19.6 21.8 26 81 27.2 83 10.7 8
19:00 0.0 20.00 2.6 0.32 9.6 12.8 17.2 21.9 22.7 27.4 25 86 26 88 0 8

7. Assessment of Standard Pollutants In A Gas Flaring Region: A Case of Ogba/Egbema/Ndoni
Local Government Area In Rivers State of Nigeria
http://www.iaeme.com/IJCIET/index.asp 13 editor@iaeme.com
Source: Abali (2015)
From the results presented, the mean concentrations of all pollutants in the various
observation points were extracted and fitting against regulatory limits as presented in
Tables 3 and 4 (See Table 6 for mean values).
Table 6 Summary of mean values of all pollutant concentrations from all locations compared
to WHO and FMEnv limits
S/N LOCATION NO2 SO2 CO O3 PM2.5 PM10
1 OBITE 31.60 0.097 10.77 0.34 10.41 18.83
2 EBOCHA 20.95 0 0.84 0.29 23.18 68
3 MGBEDE 21.47 0 0.94 0.27 26.7 68.81
4 IDU-1 19.87 0.257 14.52 0.29 16.89 57.01
5 IDU-2 19.71 0.079 5.42 0.349 18.57 78.82
6 WHO+
2 0.2 10 1 25 50
7 FMEnv*
5 0.83 5 ± 15 50
±No limit; +
Source-Campbell et al., (2004); *
Source: FMEnv (1991)
Principal Component Analysis
The principal component analysis (PCA) of the Microsoft Excel software was used to
demonstrate the relationship between the observed pollutants and the regulatory limits
of Federal ministry of environment and WHO. The PCA equally showed the
relationship between observation locations in terms of the level of the observed
concentrations (See Figure 9 for PCA plot).
Figure 9 Plot of Principal component analysis tool showing the relationship of pollutant
concentration
OBITE
EBOCHAMGBEDE
IDU-1
IDU-2
WHO
FMEnv
NO2
SO2
CO
O3
PM2.5
PM10
-3
-2
-1
0
1
2
3
-4 -3 -2 -1 0 1 2 3 4
F2(27.02%)
F1 (38.98 %)
Biplot (axes F1 and F2: 66.00 %)

8. Ify L. Nwaogazie, Abali Happy Wilson and Terry Henshaw
http://www.iaeme.com/IJCIET/index.asp 14 editor@iaeme.com
Effect of Temperature on Pollutants
The effect of temperature on the pollutant increment and reduction using the data
obtained from Obite location as an example was demonstrated. The effect of
temperature on the pollutants is presented as Figure 10 for pollutant gases and Figure
11 for particulate matter.
Figure 10 Pollutant gases concentration against ground and 10 metre height temperature
Figure 11 Particulate concentration against ground and 10 metre height temperature
0
5
10
15
20
25
30
35
40
0
5
10
15
20
25
30
35
40
TEMPERATURE
NO2CONCENTRATION
TIME OF DAY
POLLUTANT GASES CONCENTRATION WITH
TEMPERATURE
NO2 CONCT.
GROUND LEVEL
TEMP
10 METRE TEMP
0
5
10
15
20
25
30
35
40
0
2
4
6
8
10
12
14
16
TEMPERATURE
PM2.5CONCENTRATION
TIME OF DAY
PARTICULATE CONCENTRATION WITH
TEMPERATURE
PM2.5 CONCENTRATION
GROUND LEVEL
TEMPERATURE
10 METER TEMPERATURE

9. Assessment of Standard Pollutants In A Gas Flaring Region: A Case of Ogba/Egbema/Ndoni
Local Government Area In Rivers State of Nigeria
http://www.iaeme.com/IJCIET/index.asp 15 editor@iaeme.com
DISCUSSION
Observation of standard pollutants in Ogba/Egbema/Ndoni Local Government area
has shown that most of the pollutants are above regulatory limits of WHO and
FMEnv. Obite location showed very high levels of NO2, O3 and CO which were
above the WHO limits and the FMEnv limits.Ebocha and Mgbede showed very high
levels of NO2, PM2.5, O3 and PM10 which were above WHO and FMEnv limits. Idu
locations 1 and 2 showed very high levels of NO2, CO, PM2.5, O3 and PM10 which
were above WHO and FMEnv limits. All these high pollutant concentrations
measured are very visible in their effect to the environment. The high level of NO2
causes acid rain and the roofs in the study area get rusted frequently. The high level of
particulate is seen in the high amount of particulate settlement in privately owned
ponds especially fish ponds. In all SO2 pollutant is significantly small or almost zero
in the study area because the crude oil of the Niger delta contains little or no sulphur
and for this reason it is popularly known as “sweet crude”.
From the PCA plot we see the distinctive differences can be seen in the
concentration of pollutants and their closeness to areas they were observed highest in
concentration. For example the highest NO2 was recorded in Obite; from the plot it is
the closest to Obite followed by Idu location 1. It was also noticed from the PCA plot
that the FMEnv and WHO limits are significantly different but it is observed that the
WHO limits are much more sensitive than the FMEnv limits and this is why most of
the pollutant concentrations could attain the FMEnv limits and not the WHO limits. A
strong relationship between pollutant reduction, increment and ground level
temperature was recorded. Works of Henshaw et al., (2015 & 2016) have noted that
the amount of solar radiation in the Niger delta region can play a major role in
pollutant uplifting. From Figures 10 and 11 it is obvious when noting the reduction of
pollutant concentration as the ground temperature increases. All the pollutants except
Ozone are highest at night and early hours of the day. To summarised all of this, it is
obvious to state that pollutant levels for NO2, O3, PM2.5 and PM10 are in very high
concentrations. Animals, properties and plants would continue to suffer the effects
until a decision against flaring is taken up by the Government.
CONCLUSION
From this work the following conclusions can be reached:
1. NO2, O3 ,PM2.5 and PM10 are the major pollutants to expect in a petroleum
extraction region especially when the crude is sweet as the case of the Niger delta
region;
2. The WHO limits are significantly different from the FMEnv limits;
3. Temperature in the Niger delta region has significant effect in reducing pollutants
concentrations; and
4. The effect of NO2, PM2.5 and PM10 are visible in the study area through rusted roofs
and heavy particle settlements in ponds.
RECOMMENDATIONS
From the outcome of this study, the following actions are being recommended:
1. That Federal Government of Nigeria should key into the World Bank Global Gas
Flaring Reduction Initiative (GGFRI) which is aimed at reducing gas flaring as it
wastes a valuable energy resource that could be used to support economic growth
and progress in oil-producing countries;

10. Ify L. Nwaogazie, Abali Happy Wilson and Terry Henshaw
http://www.iaeme.com/IJCIET/index.asp 16 editor@iaeme.com
2. Natural gas instead of being flared should be re-injected into the formations for
future use;
3. Construction of a network of gas pipelines connecting all flow stations for
harnessing to tanks in a gas farm where homes and industry can get their supply;
and
4. Adopt smokeless flaring technology for less pollutant production especially
particulates (as immediate action while other recommendation are being
considered).
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