Creating air pollution map and analyzing traffic survey with VNU-HCM students

Osaka Prefecture University

Tomofumi Kiyose

Yusuke Suda

Takako Yamazaki

Air pollution

Economy of Vietnam is significantly developing

Reason of air pollution：◆Rapid economic growth◆Growth of populations◆Major development of industries

Especially problems in urban area

Emission from motor bikes, cars, etc.Air pollutions（CO2, NOx etc.）

Air pollutants increase in Vietnam

2Background

Purpose

Air monitoring by setting equipment in Ho Chi Minh city.→make pollution map

Compare with the result of same experiment last several year.

→discuss about the change of the pollution in Ho Chi Minh city

Sampling with Vietnamese students→attend in international joint study

3

Materials & Methods

to identify the factor of air pollution clearly

4

49 sampling points

to measure NO2 ,NH3 ,O3

1. Passive Sampler

2. Filter pack

4 sampling points

to measure PM2.5, HNO3, HONO, NO2 and NH3

3. Traffic Count

Materials & Methods

2

34

14

6

15

19

9

20

11

12

42

16 1

3

28

1

25

222

327

17

18

45

26

21

43

39

47

48

44

46

49

35

36

34

33

37

31

32

40

41

8

10

524

30

7

VNUHCM

Passive samples

+ Filter Pack

City area

What is passive sampler?

Sampler : low Atmosphere : high

Trapping filter

Diffusion of gaseous particles resulted from difference of the gaseous concentration

Principle of passive sampler

○Advantage*Not use power source*Small and light*Low cost*Easy to set and collect

×Disadvantage*Variation is over 10 %

Passive sampler

Airheight : 19 mmdiameter : 30 mmφ

pore size:1.0 mm

remove particles and water drop

Teflon filter

Filter include chemical

To catchNH3 → H3PO4

O3 → NaNO2

NO2 → N(CH2CH2OH)3

Filter pack

○Advantage

*Small and light

*Can collect samples where is no analyzers

×Disadvantage

Need power source

Analysis

Filter pack

pump

F7: TEA 20 %(NO2)F8: TEA 20 %(NO2)

0.1 L/min

3.9 L/min

Calculation

HONO concn. : F4－F5

NO2 concn. : F5×2+F7+F8

MFC

4.0 L/minAir MFC

F1: Donut filter(particle >2.5 µm)F2: Quartz filter(PM2.5)F3：NaCl(HNO3 all)F4: Na2CO3(HONO all、NO2 about 2 %)F5: Na2CO3(Compensate for NO2 of F4)F6: H3PO4 (NH3 all)

Analytical method

Passive sampler(49 places)

Material Analytical method

NH3 IC

NO2 UV-vis

O3 UV-vis

Filter pack sampler(4 places)

Material Analytical method

PM2.5 Weight measurement

HONO IC

HNO3 IC

NH3 IC

NO2 UV-vis

Program schedule

Passive sampler

Filter pack Activity

21/8 Group meeting Welcome party

22 set set Plastic factory

23 Mekong Delta

24 Change filterDalat travel

25

26 Change filterCity tour & Cultureexchange program

27 Water park

28 Collect sample Collect samples Karaoke & city tour

29 Analyzing Super market

30 Presentation Ben Tanh market

Keep

Pollution Map：NH3 (2018)

Big Highway

2 km

Tan Binh Dist

Dist. 9

Dist. 2

Dist. 4

Dist. 1

Dist. 3

Dist. 10

Dist. 11

Dist. 6

Dist. 8Dist. 7

Dist. 5

Dist. 12

Thu Duc Dist.

Binh ChanhDist.

Hoc Mon Dist.

Binh ThanhDist.

Phu NhuanDist.

Go Vap Dist.

NH3 ppb75 ~

50 to 75

25 to 50

0 to 25

Saigon River

Big Highway

City area

2018

Emission source：Waste water

NH3 Comparison 2017-18

NH3 ppb75 ~

50 to 75

25 to 50

0 to 25

2017 2018

Saigon River

Location trend is almost same

Big Highway Big Highway

Saigon River

NO2 Comparison 2017-18

NO2 ppb75 ~

50 to 75

25 to 50

0 to 25

2017 2018

Compare 2018 with 2017• NO2 concentration is higher than that of 2017.

• It had not rained much in the measurement period.2NO2 + H2O → HONO + HNO3

NO2 ppb30 ~

20 to 30

10 to 20

0 to 10

15

O3 Comparison 2016-18

2018

Different trend

[Counting period] 7 a.m. ～ 6 p.m., for 5min / 1h

[Place]• Front of VNUHCM (NVC street)• Both street (South & North side)

Standard Heavy duty Motorbike

[Type]

Traffic count

VNUHCM

0

2000

4000

6000

8000

10000

12000Bike / Monday to South

0

2000

4000

6000

8000

10000

12000

27/8/2018

28/8/2017

29/8/2016

Bike / Monday to North

Nu

mb

er

of

vie

cle

s/ h

ou

rResult：Traffic count

◆In the morning:North > South

→to go center of city

◆In the evening:South > North

→to go home

Direction to center of city

VNUHCM

Office area

Bed town

Bed town

Bed town

Bed town

Conclusion

NH3: Concentration, location trend is

same to 2017.

NO2: Concentration is higher than 2017.

Location trend is similar.

O3: Concentration is lower than 2016,2017.

Location trend is opposite from last two years.

But this year,

NH3,NO2,O3 are high value in city area.

19