IAQM Early Careers Metup, London, June 2018

1. Ras Laffan Industrial City (RLIC)
Air Dispersion Modelling Study
June 2018

2. 2
Topics
• Project Background
• Modelling approach
• Model Inputs
• Results
• Questions and Answers

3. 3
Project Background

4. 4
Qatar and Natural Gas
Qatar has the third-
largest proved reserves of
natural gas in the world
at 900 trillion cubic feet,
approximately 10% of
the world's known
reserves.
The gas produced
from this giant
field is processed
to produce LNG,
GTL, NGL, and
other gas-related
industries

5. 5
What is Ras Laffan Industrial City?
An industrial hub founded in 1996, located 80 km north of
Doha and administrated by Qatar Petroleum.
RLIC hosts some of the major operators in the gas industry:
SHELL and ORYX GTL plants, Qatargas and RasGas LNG plants,
the Dolphin gas processing plant, the Laffan Refinery, power
plants, etc…

6. 6
Setting the Scene
Our Client requires an Environmental Permit from the Ministry of Environment
(MME) for the increase in production
The project is also subject to the approval from the Industrial City Authority
(RLIC)
RLIC requires all air quality studies to be performed with CALPUFF considering
all RLIC industrial sources, while, MME accepts AERMOD modelling project
sources only.
RLIC and MME have their respective air quality standards
RLIC authority requires to model pollutant concentrations in the capital as well,
despite RLIC being 80 km from Doha

7. 7
Project Background
Increase Plant’s production target from current nominal production capacity, based on
8,000 operating hours (or 11 months)/year, as per the Consent to Operate (CTO) for
the plant
Final capacity with 24/7/365 operation at 100% feedstock processing, within years of
no scheduled turnarounds

8. 8
Air Dispersion Modelling - Approach

9. 9
Air Dispersion Modelling Approach
Modelling Approach:
• The selected model is CALPUFF
• Two meteorological years have been modelled: 2011 and 2016
• Air dispersion modelling considered:
 All sources in RLIC (i.e. 354 point sources and 35 flares) and Plant
sources (Thermal oxidiser, Boilers, Furnaces and flares)
 Main Emitted Pollutants: SO2, NOX and PM10
 Chemistry
 Terrain and Land use
 Buildings Downwash

10. 10
CALPUFF Architecture
1. Emissions Inventory
354 point sources + 35 flares for 1
yr. operational scenario
3. CALPUFF
Chemical
Transformation
RIVAD chemical
scheme
Hourly O3
Modelling
grids
10000 Discrete
receptors
2. CALMET 4. CALPOST
Terrain
&
Buildings
3b. CALPUFF can only
process 200 sources in one
run. Sources have been split
into two separate runs and
then CALSUM has been
used to create a single
concentration file.

11. 11
WRF, CALMET and CALPUFF Modelling Domain
Image source: Trinity Consultants

12. 12
Modelled Sources

13. 13
Sensitive Receptors (108) Discrete Receptors (10,0000)

14. 14
Background Data – RLIC Monitoring Stations

15. 15
Air Quality Monitoring Stations

16. 16
Modelling Results

17. 17
Modelling Results –RLIC Normal Operation
- For NO2 and PM10, RLIC Camp is used for background concentrations
- For SO2, AL-Khor is used
Modelled
(All Sources)
(ug/m3
)
Background
Concentrations
Total
(Modelled
+Baseline)
% of the
adopted AQS
Exceedance
(Yes/No)
RLIC MME
Modelled
(All Sources)
(ug/m3
)
Background
Concentrations
Total
(Modelled
+Baseline)
% of the
adopted AQS
Exceedance
(Yes/No)
RLIC MME
2nd
Highest 1-hour
Average
907 142 1049 262% Yes 400(1) 2nd
Highest 1-hour
Average
602 142 744 186% Yes 400(1)
99.9th
Percentile 1-hour
Average
336 83.6 420 105% Yes -- 400
99.9th
Percentile 1-hour
Average
328 83.6 411.6 103% Yes -- 400
2nd Highest 24-hour
Average
91 36 127 84.7% No 150(1)
--
2nd Highest 24-hour
Average
130 36 166 72.2% Yes 150(1)
--
99.7th
Percentile 24-hour
Average
65 35.7 100.7 67.1% No -- 150
99.7th
Percentile 24-hour
Average
72.6 35.7 108.3 21.6% No -- 150
Annual Average 18.6 14.7 33.3 33.3% No 100 100 Annual Average 17.7 14.7 32.4 32.4% No 100 100
2nd
Highest 1-hour
Average
5362 159 5521 425% Yes 1,300(2)
--
2nd
Highest 1-hour
Average
2582 159 2741 211% Yes 1,300(2)
--
2nd
Highest 24-hour
Average
543 30 573 157% Yes 365(1)
365
2nd
Highest 24-hour
Average
316 30 346 94.8% No 365(1)
365
Annual Average 39 7.91 46.91 58.6% No 80 80 Annual Average 38.1 7.91 46.0 57.5% No 80 80
Maximum 24-hour
Average
18.8 770 789 316% Yes 250(3)(4)
--
Maximum 24-hour
Average
23.3 770 793 317% Yes 250(3)(4)
--
99.7th
Percentile 24-hour
Average
9.62 673 683 455% Yes -- 150
99.7th
Percentile 24-hour
Average
12.1 673 685 457% Yes -- 150
Annual Average 1.18 95.9 97.1 97.1% No 100 50 Annual Average 0.93 95.9 96.8 96.8% No 100 50
Air Pollutant Parameter
Normal Scenario 2016
Ambient Air Quality Standard
(AAQS)
(µg/m3
)
Nitrogen Dioxide - Maximum Values acorss the whole modelling domain (ug/m3)
Sulphur Dioxide - Maximum Values acorss the whole modelling domain (ug/m3
)
(4)
Maximum concentration not to be exceeded more than once per year
Notes:
(1)
Maximum concentration not to be exceeded more than once per year
(2)
Maximum concentration not to be exceeded more than once per year
PM10 - Maximum Values acorss the whole modelling domain (ug/m3
)
(4)
Maximum concentration not to be exceeded more than once per year
PM10 - Maximum Values acorss the whole modelling domain (ug/m3
)
Notes:
(1)
Maximum concentration not to be exceeded more than once per year
(2)
Maximum concentration not to be exceeded more than once per year
(3)
Exceeding of24 hours particulate matter only ifman-made (3)
Exceeding of24 hours particulate matter only ifman-made
Nitrogen Dioxide - Maximum Values acorss the whole modelling domain (ug/m3
)
Sulphur Dioxide - Maximum Values acorss the whole modelling domain (ug/m3
)
Air Pollutant Parameter
Normal Scenario 2011
Ambient Air Quality Standard
(AAQS)
(µg/m3
)

18. 18
Analysis of NO2 and SO2 Exceedances
- PM10 Exceedance is due high existing background
concentration
Exceedances are all
located within RLIC
boundaries
Parameter Maximum
(µg/m3)
Year, Julian Day,
Start Hour
X(m) Y(m)
2nd Highest 1-
hour NO2
Average
907 30th
September 2011
Time: 7 AM
547357 2865929
461
27th
March 2016
Time: 7 AM
546557 2868729
2nd Highest 1-
hour SO2
Average
5362
5th
January 2011
Time: 2 AM
552357 2866929
1798
28th
April 2016
Time: 9 AM
552758 2865144
2nd Highest 24-
hour SO2
Average
543 5th January 2011
Time: 0 AM
552557 2866929
209 12th
February 2016
Time: 0 AM 556557 2861129

19. 19
Annual NO2

20. 20
2nd Highest 1-hr NO2

21. 21
2nd Highest 1-hr NO2 Exceedances Count

22. 22
Annual SO2

23. 23
2nd Highest 1-hr SO2

24. 24
2nd Highest 1-hr SO2 exceedance

25. 25
Plume Animation

26. 26
Modelling Results – Study Outcome

27. 27
Study Outcome
• The model is performing well- the modelled concentrations are in agreement
with the monitoring measurements.
• There is an exceedance at some receptors within the RLIC boundary for the 1-
hour NO2 and SO2 concentrations. This exceedances are not captured by the
monitoring stations, suggesting that the monitoring network is should be
extended.
• Exceedance of RLIC and MME limits for PM10 is due to high existing background
concentrations for Operational Scenarios (no mitigation measures proposed).

28. 28
Mitigation Measures
• At the Plant, furnaces account for 80 % of 2nd highest 1-hr NO2 concentrations
and 60 % of the total NO2 emissions at the point of maximum modelled
concentration.
• This suggests that measures aimed to reduce NO2, should target furnaces.
• The Plant is currently in progress to install a new type of low NOx burners at the
furnaces that will reduce the flame impingement and consequently reduce the
resulting NO2 concentrations.
• A lower content of NOx will generate lower NO2 emissions and consequently a
reduction in NO2 concentrations at receptors.

29. Thank You