NCKH BLACK CARBON EMISSION FROM RICE STRAW OPEN BURNING IN SOME PROVINCES OF THE RED RIVER DELTA

VIETNAM NATIONAL UNIVERSITY, HANOIVNU UNIVERSITY OF SCIENCE FACULTY OF ENVIRONMENTAL SCIENCE BLACK CARBON EMISSION FROM RICE STRAW OPEN BURNING IN SOME PROVINCES OF THE RED RIVER DELTA

VIETNAM NATIONAL UNIVERSITY, HANOI

VNU UNIVERSITY OF SCIENCE

FACULTY OF ENVIRONMENTAL SCIENCE

BLACK CARBON EMISSION FROM RICE STRAW OPEN BURNING

IN SOME PROVINCES OF THE RED RIVER DELTA

Supervisor: Assoc.Prof.Dr Hoang Xuan Co

Student: Vu Thi Hanh

• Black Carbon (BC)

- One of the Short-live Climate Forcer

- The second most important contributor to global warming

- Having negative impacts on climate, public health, agriculture and ecosystem

• The RRD is the second most important rice-producing area in Vietnam; rice

cultivation generates huge amounts of rice straw

• Burning rice straw in the field becomes a popular activity  main source of BC

aerosol and directly effect on local air quality

• Method to estimate or measure BC emission are neccesary

Chapter 1: Overview

• 1.1 Black Carbon

• 1.2 Study area

• 1.3 Rice straw burning in the field

Chapter 2: Objects and Methodology

• 2.1 Objects to study

• 2.2 Methodology

Chapter 3: Results and Discussions

• 3.1 Summary data acquistion

• 3.2 Estimate Black Carbon emission

• 3.3 Compare the results of the two approaches

• 3.4 Measurement of Black Carbon

• 3.5 Solution to reduce rice straw open burning

Chapter 1

1.1 Black carbon

• Production of incomplete

combustion

• Consisting of soot, charcoal, and

possible light-absorbing refractory

organic matter

• Having short atmospheric lifetime 

One of the short-lived climate

forcers

Transmission electron microscopy image of

a representative soot particle

Source: US EPA

1.1 Black Carbon

1.1.2 Sources of Black Carbon

• Natural sources: include erupting volcanoes, wildfires

Erupting volcanoes Wildfire

• Anthropogenic sources:

Source: US EPA

Black Carbon aggregates

Source: Bond et al, 2013

1.1 Black Carbon

1.1.4 Impacts of BC

 Climate impacts:

- Direct radiative forcing:

Change in the energy

balance due to absorption and

scattering of sunlight

-Interactions with clouds:

+ Changing cloud distributions

+ Changing the number concentration

of liquid cloud droplets

-Snow/ice albedo effect:

Reduced albedo  Increases surface

melting

-Other impacts:

Change in precipitation patterns 

Change surface dimming BC direct radiative forcing

Source: T.C Bond

1.1 Black Carbon

 Health public impacts

- BC visibility associated with PM2.5

- Result in millions of premature deaths worldwide, including:

+ Aggravation of respiratory + Cardiovascular disease

+ Impaired lung function+ Changes in heart rhythm

- Reducing BC can prevent 640,000 to 4,900,000 premature deaths every year

 Agriculture and ecosystem impacts:

- Reduce agricultural production

- Affect ecosystems’ carbon uptake

- Affect metabolic processes of foliage

- Topography: mainly flat (0.4 – 12m

above sea level)

- Including 11 provinves and cities

- High population density

- The second most important

rice-producing area, accounting 15.2% of

the national crop

Hanoi Vinh Phuc Ninh Binh

Natural

condition Topography Plainmountainous, midland, Plain, midland, mountainous Plain, hill and mountain, area the coastal

Climate Humid subtropical Tropical monsoon Trophic and monsoon Hydrology Red River, Da River, Duong

River, Cau River Red River, Lo River, Day River, Hoang Long River, Boi River, Vac River,

Socio-economic

situation

The economic structure Region 1: 5.36%Region 2: 41.56%

- The area of planted forests: 237.1 ha

- Total area planted with annual crops: 96.05 thous.ha

- The area of planted forests:

884 ha

- Aquaculture area: 6,926 ha

- Total area planted with annual crops: 110.4 thous.ha

- Aquacultural area: 10.2 thous.ha

- The area of planted forests: 20.85 thous.ha

Table: National condition and socio-economic situation by provinces

- Corn production:

+ Total area: 140.8 ha + Yeilds: 6.94 tons/ha

- Sweet potatoes, cassava:

+ Totao area: 62.64 ha + Yeilds: 6.94 tons/ha

- Industrial crop production:

+ Artemisia annua: area of 116 ha;

+ Peanut: area of 52.7 ha;

+ Vegetables and soybean: area of 81.7 ha;

+ Tea: area of 82 ha;

+ Fruit trees: area of 180 ha.

- Rice production:

+ Total area: 303.6 ha + Production: 1,219.062 tons

- Vegetables:

+ Total area: 13.5 ha

Table: Agricultural production situation of commune in province, 2013

Athletic Education - sports center:

- It is located in Tu Liem district, Hanoi city

- Measurement point is less affected by

other sources of BC such as

transportation, industrial process and

residential cooking (coal, wood, )

1.2 Study area

1.3 Rice straw burning in the fields

Using other fuels such as gases,

biogas, wood, solar energy replace

for rice straw

Using tiled roofs and roofslab

replace for rice straw

Farmers believe that RSOB can kill

pests and weeds and produce

nutritional elements for soil

Decreasing needs to use rice straw

for feeding animals

Rice Straw Open Burning (RSOB):

- 77% in the Northern Vietnam

- 51% for the spring paddy crop, 78.5%

for seasonal paddy crop in Thai Binh

Chapter 2: Objects and methodology

The main objective: develops a method for estimating BC emission from RSOB

- Estimation of BC emission in three provinces of RRD by two approaches

- Measurement real-time BC concentration in Ha Noi

- International journals

- Province websites

i,j : Pollutant i and crop type j

Emi,j : Emission of pollutant i from crop type j

Mj : amount of burned biomass from crop type j (kg/year)

M j = P j × S j × D j × B j ×  j (2.2)

Where,

P j : Crop production (tons/year)

S j : Crop-specific residue-to-production ratio (fraction) = 1.19

D j : Dry matter-to-crop residue ratio (fraction) = 0.85

B j : Fraction of dry matter residue that are burned in the field

j: Crop-specific burn efficiency ratio (fraction oxidized during combustion) = 0.89

EFi,j : Emission factor of pollutant i from crop type j (g/kg of dry matter) = 0.51

Methodology

Analysis & data processing

• BC emission per capita

BC emission per capita = ∑EmBC / rural population (2.3)

Where, EmBC: emission of BC (g/year)

• Comparison BC emission by province of two approaches

Approach 1

Use BC emission per capita of commune

Approach 2

Use total production of paddy by province

EBC = Emission per capita × rural population of

province (2.4)

Rural population is the population of the

territorial units to which the State is defined

rural areas [GSO].

EmBC = ∑ M × EFBCM: Amount of burned rice (define by equation 2.2)

EFBC: Emission factor of BC (0.51)

Methodology

Measurement BC concentration

• MicroAeth® Model AE51

- High quality, short time resolved

data

- High sensitivity, miniature,

portable

• Measurement at 880 nm; it is

appropriate for measurement BC

concentration from biomass

burning

MicroAeth® Model AE51

Methodology

Measurement BC concentration

• Data is saved automatically for 5

minutes for 7 days from 20th to 26th

of October This time is the period

after harvesting of suburban

districts

• Meteorological factors such as

wind direction, wind speed,

temperature, humidity, pressure

was also measured at the same

time

Field survey method

• Asked about the

• Visited some models

that use rice straw to

grow mushrooms

and feed redworms

Chapter 3

3.1 Summary data acquistion

Table Production of paddy and average rural population by province in 2013

Table Production of paddy and average rural population by commune in 2013

3.2 Estimate BC emission

Commune Fraction of rice straw that are burned in the field (%)

Tho Xuan 227604 303472 379341 455209 531077 606945 682813Ngoc Thanh 1216204 1621606 2027007 2432409 2837810 3243212 3648613Gia Xuan 329233 438977 548721 658465 768210 877954 987698

Commune Fraction of rice straw that are burned in the field (%)

Vinh Phuc 0.083 0.111 0.139 0.167 0.194 0.222 0.250

Ninh Binh 0.125 0.166 0.208 0.249 0.291 0.332 0.374

Table Production of rice straw burning in the filed by commune

Table Production of rice straw burning in the filed by province

Unit: kg/ha

Unit: thous tons

The best etimation for fraction burned in the fields is 80% in Hanoi, 60% in Vinh Phuc,

3.2 Estimate BC emission

Approach 1: Use BC emission per capita of commune

Table Annual BC emission from RSOB by commune in 2013

Commune Fraction of RS that are burned in the field (%)

3.2 Estimate BC emission

Approach 1: Use BC emission per capita of commune

Table Annual BC emission from RSOB by province in 2013

Note: Values in brackets () are rural population of province in 2013 (thous.persons), 1Gg = 10 9 g

Approach 2: Use total production of paddy by province

Table Annual emission of BC from RSOB by province in 2013

Province Fraction of RS that are burned in the field (%)

3.3 Compare the results of the two approaches

The difference between two approaches due to the homogeneity of the communes in the

province, including structure of agriculture, RS fraction burned in the fields and rural population

Figure BC emission in three provinces for two approaches

3.4 Measurement of BC concentration

- Average concentration of BC in Ha Noi

is 5.03µg/m3, the highest concentration

reaches 16.1µg/m3

- BC concentration in Hanoi is rather

higher than the one in some urban

area of developed countries

+ United State: 0.3-3.0 µg/m3 (2007)

+ Canada: 0.9-1.8 µg/m3 (2003-2009)

+ United Kingdom: 1.0-2.9 µg/m3(2009)

( Source: US EPA)

Figure Average hourly concentration of BC

- Wind blows, especially from Northwest (Hoai Duc, Dan Phuong, Dong Anh) and Southeast (center of Ha Noi city)  High BC concentrations in measurement point

3.5 Solutions to reduce rice straw burning in the field

Rice straw

Growing mushroom

Energy production

Feeding redworms

Composting

organic fertilizers

3.5 Solutions to reduce rice straw burning in the field

• Using rice straw for

- Waste of mushroom use

for growing fresh

vegetables as organic

fertilizers

3.5 Solutions to reduce rice straw burning in the field

• Using RS for feeding

redworms of Ms

Nguyen Thi Nga

- Rice straw and waste

used to grow fresh

vegetables, fruit trees,

fish and chicken

CONCLUSIONS AND RECOMMENDATIONS

1 Conclusions

• Estimation of BC emission from RSOB

- RSOB is a popular activity in the rice-growing areas

- The best estimation of BC emission:

+ In approach 1: 0.127 Gg/year for Ha Noi, 0.079 Gg/year for Vinh Phuc and 0.066 Gg/year for Ninh Binh

+ In approach 2: 0.425 Gg/year in Ha Noi, 0.085 Gg/year in Vinh Phuc and 0.106

Gg/year in Ninh Binh

- The difference between two approaches due to the homogeneity of communes in the province

2 Recommendation

- Further research focuses on the measurement these parameters of emission

factors, crop residue to crop ratio, fraction burned of crops at the field, biomass density, burning efficiency for rice and other crops

- Emission per capita and fraction burned should be calculated for each commune

in province to avoid uncertainty from homogeneity between communes

- Monitor and measurement should be encouraged to compare between real data and estimation data

- To reduce BC emission from RS burning, it is necessary to develop a better

management system to cutting or reducing crops residue open burning, including

RS Further study about local condition to have suitable and sustainable methods for each region