This presentation was given in Athens during the Air Pollution Conference in 2012. It deals with research made during the Sulfur change in the diesel fuel used in the Aburra Valley in Colombia

1. THE EFECT OF THE DIESEL FUEL
SULPHUR CONTENT ON THE PM2.5
POLLUTION PROBLEM IN THE ABURRÁ
VALLEY REGION AROUND MEDELLÍN,
COLOMBIA
Enrique Posada (1) , Myriam Gómez (2)
(1) INDISA S.A ,Carrera 75 # 48 A 27, Medellín, Colombia
(2) Politécnico Colombiano, Medellín, Colombia
enrique.posada@indisa.com
mgomez@elpoli.edu.co
8th International Conference on Air Quality - Science and Application in
Athens, 19-23 March 2012.

2. THE ABURRÁ VALLEY REGION WITH THE CITY OF MEDELLÍN , COLOMBIA

3. Colombia is in South America
It has a 46 million population
The Aburrá Valley 3.5 million people
Medellín 2.7 million people
diesel gasolina
Number of vehicles 90.000 590.000

4. Under the pressure of the
environmental
authorities, the national
provider of diesel fuel
decided to supply the
region with low sulfur
diesel, to contribute to the
lowering of the PM2.5
concentrations in the air.
S contents went down
from 2,100 ppm to 500
ppm and then to 50 ppm
between the end of 2009
and the first six months of
2010

5. The region counts with a metropolitan metro train very well cared
by everybody under the “CULTURA METRO”

6. There are several
innovative urban cable
mass transportation
systems and a new
natural gas metro bus

7. But there are still
large amounts of
diesel operated
buses and trucks, of
which many are
somewhat old and
operated under
inefficient conditions
which produce
frequently black
smoke visible fumes.

8. Estimated yearly PM2.5 vehicle emissions in the Aburrá Valley region
Type of vehicle Units Diesel Gasoline Total
Number of vehicles 86,972 571,109 658,081
Distance travelled per vehicle-
year Km 20,000 6,000 7,850
Emission factor for PM2.5 , low
estimate mg/km 7.57 0.35 2.78
Emission factor for PM2.5 , high
estimate mg/km 468.0 41.6 185.2
Emission factor for PM2.5 ,
laboratory study mg/km 221.9
Estimated yearly emissions tons/year 600 105 705
Diesel engines generate much larger PM emissions than gasoline engines.

9. Table 2. PM2.5 concentrations in stations in the studied region, micrograms/Nm3 and PM2.5
chemical composition (average % +/- 1.5 standard deviations) before changes in S content in
diesel
Stations Unal Poli S. Antonio Bello Itagüí All stations
Samples 7 7 38 30 30 112
PM 2.5 conc. 27.6+/-6.7 32.7+/-17.4 37.2+/-9.6 43.1+/27.7 25.9+/-10.7 33.7+/-17.6
OC 20.7+/-4.3 25.14+/-4.5 20.48+/-5.1 25.68+/-6.4 26.02+/-5.5 23.78+/-4.3
EC 40.11+/-5.0 23.31+/-5.7 37.18+/-7.0 30.4+/-10.5 26.56+/-7.0 31.53+/-7.6
Sulfates 12.66+/-2.6 16.26+/-3.4 15.35+/-7.6 13.9+/-2.41 15.1+/-4.62 14.69+/-3.3
Nitrates 0.35+/-0.11 0.62+/-0.21 1.35+/-1.46 0.75+/-0.42 1.33+/-1.16 0.98+/-0.73
Sodium 1.21+/-0.35 1.92+/-0.67 1.26+/-0.68 1.23+/-0.32 2.87+/-1.74 1.71+/-0.93
Ammonium 4.01+/-1.38 4.68+/-1.71 5.28+/-2.52 4.23+/-0.98 3.87+/-1.42 4.44+/-1.23
SO3 1.09+/-0.29 1.45+/-1.22 0.46+/-0.74 1.21+/-0.67 0.65+/-0.47 0.90+/-0.58
SiO2 1.36+/-0.67 1.86+/-0.95 1.04+/-0.83 1.07+/-1.56 1.64+/-1.01 1.33+/-0.79
Fe2O3 0.64+/-0.45 0.99+/-0.79 0.65+/-0.46 0.82+/-0.36 0.76+/-0.21 0.76+/-0.30

10. Laboratory emission sampling in a diesel motor bench.
Motor (ISUZU 4JA1 Type I turbocharged, rotating pump direct injection, 2499 cm3,
four cylinders in line, compression ratio 18.4, nominal power 59 KW at 4100 rpm)
Fuel with three sulfur contents: 2,100, 500 and 50 ppm
Two different load conditions (4.75 and 24.0 kW), associated with two different motor
rotating speeds.(1,770 and 2,420 rpm).
Samples were taken with an isokinetic sampling unit capable of separating PM samples
in three fractions (<2.5, 2.5-10, >10 microns).

11. Environmental sampling in a tunnel serving the Aburrá Valley region
Concentrations and samples of PM2.5 in the FERNANDO GOMEZ MARTINEZ
tunnel were taken during complete 24 hour periods, at several times in 2010,
in which there was certainty about the sulfur content of the diesel fuel used
by the vehicles in the Aburrá Valley region. In this way the said three types of
diesel fuel, with S content 2,100, 500 and 50 ppm could be correlated with
the samples.

12. Environmental sampling in two sites in the Aburrá Valley region
Two (2) PQ-200, BGI Instrument, (equipped with Teflon and Quartz filters)
were placed two (2) zones of the Aburrá Valley [Instituto Politecnico Jaime
Isaza Cadavid (Poli) and Universidad Nacional- Facultad de Minas (Unal)] in six
(6) alternate measurement campaigns, with two simultaneous ones for both
sites. Samples were taken during complete 24 hour periods, in such a way
that they could be correlated with the ongoing changes in the diesel fuel S
content (2,100, 500 and 50 ppm respectively). A total of 50 samples were
collected in each area.

13. Analysis
In the three studies, samples were taken with Tefón and Quartz filters and subjected to
chemical analysis in Laboratory Alpha in Colombia for metallic oxides and in the DRI
(Reno, Nevada) for ions and carbonaceous species (EC and OC). Analytical techniques
used were Spectrofluorometry, 3D Polarized Energy Dispersive X-Ray Fluorescence
(Epsilon Model 5), for the determination of mineral oxides; ion chromatography
(Dionex Model 3000) for the quantification of anions and cations; and the IMPROVE-A
Thermal Method Protocol for the determination of organic carbon and elemental
carbon.

14. PM 2.5 specific emissions in diesel laboratory bench motor study
Sulfur in diesel fuel, ppm 50 500 2,100 50 500 2,100
Motor rotational speed,
rpm 1,770 1,770 1,770 2,420 2,420 2,420
Motor mechanical power,
kW 4.69 4.76 4.75 24.1 23.9 23.9
PM 2.5 emissions, kg/ton
fuel 3.76 5.50 8.76 0.81 0.78 2.55
OC, kg/ton fuel 2.234 3.303 5.239 0.275 0.218 0.526
EC, kg/ton fuel 0.060 0.068 0.175 0.293 0.328 0.949
Sulfates, kg/ton fuel 0.0396 0.1166 0.1638 0.0130 0.0203 0.6244
Nitrates, kg/ton fuel 0.0468 0.0554 0.0383 0.0046 0.0036 0.0032
Sodium, kg/ton fuel 0.0479 0.0549 0.0501 0.0043 0.0068 0.0292
OC, % of PM 2.5 59.42 60.01 59.83 34.09 28.16 20.63
EC, % of PM 2.5 1.60 1.24 1.99 36.35 42.31 37.22
Sulfates, % of PM 2.5 1.05 2.12 1.87 1.62 2.61 24.49

15. 10
PM 2.5, kg/ton fuel. 2
8 R = 0.98
6
PM 2.5 and sulfate in PM 2.5
4 2
R = 0.95 emissions diminish with
2
lower S in diesel fuel.
0
0 800 1,600 2,400 The effect depends on
S in diesel, ppm motor load.
PM 2.5 kg/ton fuel at 4.75 kW, average = 6.01
PM 2.5 kg/ton fuel at 24 kW, average = 1.38
0.8
Sulfates in PM 2.5
2
0.6 R = 0.96
kg/ton fuel.
0.4 2
R = 0.81
0.2
0.0
0 1,000 2,000 3,000
S in diesel, ppm
S ulfates kg/ton fuel at 4.75 kW, average = 0.11
S ulfates kg/ton fuel at 24 kW, average = 0.22

16. 5.00
4.00
% of PM 2.5 .
3.00
In the tunnel there was a
2.00
clear diminution of sulfate
1.00
salts in the PM 2.5 with the
0.00
lowering of the sulfur in the
0 800 1,600 2,400
diesel fuel.
S in diesel, ppm
S ulfates Amonium Ions, total
Major results in study in tunnel
S in diesel fuel, ppm 2,100 500 50
PM 2.5 micrograms/m3 225 420 249
Vehicles per hour 268 389 361
OC in PM 2.5 , % 23.8 22.7 25.8
EC in PM 2.5 , % 56.3 59.5 55.5
Sulfates in PM2.5 , % 2.10 1.23 0.50

17. PM2.5 concentrations in stations in the studied region, micrograms/Nm3 and PM2.5 chemical
composition (average % +/- 1.5 standard deviations) during changes in diesel S content
Station Poli Unal Poli Unal Poli Unal
S in fuel, ppm 2,100 2,100 500 500 50 50
PM 2.5, micrg/m3 32.7+/-17.4 27.6+/-6.9 26.6+/-22.3 31.4+/-13.6 27.9+/-11.4 32.8+/-12.8
OC, % 25.14+/-4.4 20.7+/-4.3 27.6+/-6.3 22.6+/-5.8 27.5+/-4.8 23.4+/-5.0
EC, % 23.3+/-5.7 40.1+/-5.0 27.6+/-10.4 44.2+/-9.3 25.9+/-6.3 44.7+/-6.2
Sulfates, % 16.26+/-3.4 12.66+/-2.6 11.69+/-7.2 7.44+/-3.7 11.25+/-3.3 7.14+/-1.8
Nitrates, % 0.62+/-0.21 0.35+/-0.11 0.56+/-0.51 0.45+/-0.48 0.55+/-0.32 0.57+/-0.75
Sodium, % 1.92+/-0.67 1.21+/-0.35 1.94+/-1.31 1.03+/-0.77 1.77+/-0.78 0.79+/-0.55
Ammonium, % 4.68+/-1.71 4.01+/-1.38 2.11+/-2.4 2.07+/-1.77 2.86+/-1.3 2.15+/-1.57
SO3, % 1.45+/-1.22 1.09+/-0.29 1.01+/-0.77 1.09+/-1.63 1.49+/-1.16 0.80+/-0.38
SiO2, % 1.86+/-0.95 1.36+/-0.67 2.0+/-1.58 1.64+/-1.33 2.45+/-2.38 1.19+/-1.09
Fe2O3, % 0.99+/-0.79 0.64+/-0.45 1.54+/-0.99 1.16+/-0.85 1.9+/-0.89 1.01+/-0.49

18. PM2.5 conc. 160 2100 160 2100
PM2.5 conc.
120 120
1400
S ppm
1400
S ppm
80 80
700 700
40 40
0 0 0 0
0 120 240 360 0 120 240 360
S ampling day, starting 2009/11/17 S ampling day, starting 2009/11/17
PM 2.5, micrograms/m3, av= 31.5 +/- 14.0 PM 2.5, micrograms/m3, av= 31.5 +/- 14.0
S in diesel, ppm S in diesel, ppm
PM 2.5 and sulfate in PM 2.5 concentrations diminish with lower S in diesel fuel for
the samples taken in the urban areas.
30
Sulfates in PM2.5 % .
30
Sulfate in PM 2.5,% .
25
20
20
10 15
10
0 5
0 120 240 360 0
Day of sampling (starting 2009/11/17) 0 800 1600 2400
S in diesel ppm
Itagüi Bello S an Antonio Poli Unal Itagüi Bello S an Antonio Poli Unal

19. CONCLUSION
A clear link was established between diesel sulfur content
and PM 2.5 compositions and concentrations, which
indicates the large influence of diesel fuel vehicles impact
on the pollution situation in the region and the importance
of this sulfur diminution.
The impact is quite clear on the chemical PM 2.5
compositions which show a significant diminution of
sulfates and ammonium salts.
The impact on concentrations is detectable but is affected
by the operational conditions of diesel equipment, vehicle
age and operational practices.
The impact was detectable in PM2.5 urban concentrations
and sulfate salts in PM2.5

20. Thank you very much for your
kind attention
COLOMBIA IS PASSION