Natural Resources of Bangladesh

•Population
•Land
•Water (ground & surface)
-Sea, River, Pond and Ground water etc
•Air
•Sun
•Forest
•Energy
•Animals & Birds
•Mines
-Oil, Coal, Natural Gas
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 What are the major problems regarding
resources with Dhaka City right now?
• Waste Generation and Management
• Mismanagement of traffic systems
• Mismanagement-or-Shortage of
Energy/Electricity: Due to lack of energy and
inefficiency in use and production of energy
• Shortage of potable water supply
• Pollution: Due to mismanagement of solid and
industrial waste, misuse of water, polluting air
(mainly through vehicle, brick field, developmental works)
• Land Degradation: Due to over use of land,
dense population in per capita area
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 Ways to use resource efficiently
Efficiently use existed Use Renewable energy like
energy –
-Solar Energy
Do not misuse electricity -Wind Energy
Do not waste water -Energy from Natural Gas
Recycle solid waste -Energy from Solid waste
Do not misuse natural gas

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 As a student/citizen how can you save
your scarce resources for future?
You have to change your behavior in some of your daily activity

• Do not use too much electricity in day time, do not turn on lights
unnecessary, turn off your lights when you will go outside your room.
• Use energy saving equipments like…….
• Turn of you stoves when you have done your cooking.
• Try to do gardening in your home, plant trees.
• Manage your household solid waste, try to recycle your waste, avoid
using polythenes and plastics.
• Dump your waste in proper places.
• Do not use vehicle un-necessarily where there is a walking distance.
Try to use cycles, bus as vehicle to reduce emissions.
• Know the causes and remedies of environmental pollution.
• Let other people know about your environmental concern through
sharing information with family and peers.
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Atmospheric Basics

5
 Structure of the Atmosphere- Layers of
the atmosphere
• There are 4
layers in the
atmosphere,
Each layer differs
in composition
and temperature.
• They are the
troposphere,
stratosphere,
mesosphere and
thermosphere.
6
 Troposphere
• Where weather happens
• Location - surface to about 10 km.
• Composition - unpolluted air: Nitrogen (78%) Oxygen (21%).
Remaining 1% is CO2 (0.0365%), H, He, Ar.
– Water vapor is an additional variable amount, .01% to
5%.

Stratosphere
• Where jets fly (at the bottom of it)
• Location - Above troposphere, about 10-50 km. Very thin
air - virtually no weather, and no turbulence.
• Composition- Similar to troposphere, except
– water vapor is 1000 x less
– ozone is 1000 x greater. 7
 Mesosphere
• This layer is above
the stratosphere
• It’s elevation ranges
from 50 to 100 km

Thermosphere
• This is the highest layer
of the atmosphere
• It’s height ranges from
100 to 400 km

8
 Air Pollution
• Atmospheric conditions both urban and rural areas are
deteriorating due to air pollution.
• Uncontrolled emission from motor vehicles, dust, industrial
waste product, construction dust, garbage, brick kilns,
cooking stoves, burning of wood, coal and bio-mass are
mainly responsible.

• Common pollutants: Dust, Carbon monoxide, Nitrogen

oxides & Sulpher dioxide, Respirable Suspended Particulates
(RSP), Smoke etc.
• Effects on human health such as chronic bronchitis, acute
respiratory infection in children, lung cancer, Stroke & Heart
diseases, abnormality during birth.
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 Air Quality of Dhaka City
• Dhaka is the eighth largest megacity of the world and home to
Around 25 million people living in an area of 306.38 square
kilometres.
• Air pollution is emerging as a major problem in Dhaka and other
cities of Bangladesh.
• The main sources of air pollution in Dhaka are vehicles,
industries particularly brick kilns, re-suspended dust and
biomass burning, Developmental Works etc.

• Contributing factors for vehicular emission in Dhaka are: poor fuel

quality, poorly maintained vehicles, inadequate transport
infrastructure, lack of proper transport planning and management.
• PM 2.5 is the controlling pollutant of Dhaka’s air quality during
90% days of the year.
• A World Bank study says nearly 2x105 tons air pollutants are
emitted from motor vehicles alone.
• Another World Bank study says as many as 15,000 deaths, a
million cases of major illness and 8.5 million cases of minor 10
illness are caused by air pollution in Dhaka and three other cities
Traffic Emissions

Initiatives so far taken:

❑ 20 years old vehicle banned ❑ Severe traffic jams in the street of Dhaka
❑ Ban of leaded gasoline
❑ Trying to use low sulfur content fuel
❑ Improvement of traffic signals
❑ Ban of track and heavy duty vehicle during day
time
❑ Change of holidays for shopping malls
❑ Change of routes of different bus lines
❑ Car free day for selected areas 11
Brick kilns emissions:
Coal is the main fuel for the brick
Kilns, power plant, rice mils.

About 1000 brick kilns in and around

Dhaka mega city; and about 12000
brick kilns are in all over
Bangladesh operating only winter time.

Coal has also high sulfur and Hg.

❑ Ban of biomass burning in the brick kilns

❑ Stack height not less than 120 ft
❑ Phase out of traditional kilns to relatively
modern kilns.
❑ Rules for not cutting soil from
agricultural land or from hills.
❑ Rules also for not setting the kilns near
residential location
 What are the impacts of Air pollution?
o Human Health
o Climate Change/Global warming
o Visibility reduction
o Agriculture
o Atmospheric Chemistry
o Ecosystem
 Principal pollutants and sources of air
pollution in Dhaka City
Principal pollutants Sources

Particulate Matter (PM10, Vehicle, Brick Kiln, Cooking,

PM2.5) Combustion

Nitrogen Dioxide and Fuel burning

Carbon Monoxide

Sulphur Dioxide Coal burning

Ozone Photochemical Reaction

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 Key issues identified in respect of
Vehicle Emission Control
- Poor fuel quality
- Many of the vehicles ply on the road are very old, worn out,
poorly maintained and often overloaded
- Poor inspection and maintenance
- Poor enforcement of existing laws in the Motor Vehicles
ordinance and unfairment and mismanagement of concern
Authorities
- Street congestion due to mixed traffic
- Inadequate facilities for manually driven tricycle rickshaws
- Poor traffic management
- Poor traffic signaling system
- Lack of pavement for street walkers
- more.. 15
 (microgram/ m3)

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100
200
300
400
500
600

0
12/25/2002
12/26/2002
12/27/2002
12/28/2002
12/29/2002
12/30/2002
12/31/2002
01/01/2003
01/02/2003
Taxis (Phase-II)

01/03/2003
01/04/2003
01/05/2003

01/06/2003
01/07/2003
Levels of PM10 before and after removal of Baby

16
PM10
Average
 What is AQI?
❖The Air Quality Index (AQI) is a public information tool
to express the air pollution level for a particular area on
a certain period
❖A pollutant's index is its concentration
expressed as a percentage of the relevant air
standard
❖This is a simple way of describing the quality of air
from human health point of view
❖The AQI is linked to the National Ambient Air Quality
Standards (NAAQS) which is set based on health
impacts 17
 Purpose of AQI
❖To give complex information about the air pollution
level and the quality of air in a simple way that people
can easily understand;

❖To inform how clean or polluted air you are breathing

in relation to health based objectives; and

❖To advise the people about the general health effects

associated with different pollution levels.

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 Air Quality Index (AQI)

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 Criteria Pollutants
U.S. EPA uses six " Criteria Pollutants " as indicators of air
quality, and has established for each of them a National
Ambient Air Quality Standards:
• Particulate matter
• Ground-level ozone
• Nitrogen dioxide
• Carbon monoxide
• Sulfur dioxide
• Lead
When an area does not meet the air quality standard for one of the
criteria pollutants, it may be defined as non-attainment (especially
for ozone, carbon monoxide, and some particulate matter).
Non-attainment classifications may be used to specify what air pollution
reduction measures an area must adopt, and when the area must 20
reach attainment.
 Control strategy development
How to determine the best approach to provide the emission reductions
necessary to achieve the air quality goal. Three primary considerations in
designing an effective control strategy are:
E E E (Environmental Engineering Ecomomic)
)1( Environmental: factors such as equipment locations, ambient air quality
conditions, adequate utilities (i.e., water for scrubbers), legal requirements,
noise levels, and the contribution of the control system as a pollutant ;
)2( Engineering: factors such as contaminant characteristics (abrasiveness,
toxicity, etc.), gas stream characteristics, and performance characteristics of
the control system; and
)3( Economic: factors such as capital cost, operating costs, equipment
maintenance, and the lifetime of the equipment.

Pollution prevention should also be considered (eliminating pollution emissions

at the source, substituting toxic raw materials, alternative processes, …)
21
 There are Four Main Steps in
Developing a Control Strategy
.
(1) Determine priority pollutants - based on health effects and the
severity of the air quality problem.

)2( Identify control measures. For specific source categories, choose

the appropriate controls

(3) Incorporate the control measures into a plan - written plan with
implementation dates to formalize the strategy. It is important to
adopt a regulatory program and include it in the plan so that control
measures will be enforceable .

)4( Involve the public. As with the other management activities related
to the AQM process, it is critical to contact the regulated community
and other affected parties, as the public should be consulted as
part of the strategy development process.
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 Methods of Air Pollution Control

Mechanical Collectors
(dust cyclone) NOx Control
Pollution
Electrostatic Precipitators VOC abatement
Control

Baghouses Acid Gas/SO2 control

Devices
Scrubbers Mercury Control

➢These items are commonly used as pollution control devices by

industry or transportation devices.
➢They can either destroy contaminants or remove them from an 23
exhaust stream before it is emitted into the atmosphere.
 The Clean Air Act
• The Clean Air Act of 1963 is a United States federal law
designed to control air pollution on a national level. It is one of the
United States' first and most influential modern environmental
laws, and one of the most comprehensive air quality laws in
the world. Authorizes EPA to set limits on amount of specific air
pollutants permitted.
• Focuses on 6 pollutants:
– lead, particulate matter, sulfur dioxide, carbon monoxide,
nitrogen oxides, and ozone
• Act has led to decreases!

Other Ways to Improve Air Quality

• Reduce sulfur content in gasoline
– Sulfur clogs catalytic converters
• Require emission standards for all passenger vehicles
– Including bus, trucks and minivans
• Require emission testing for all vehicles
– Including diesel 24
 Air Pollution Around the World
• Air quality is deteriorating rapidly in developing
countries
• Shenyang, China
– Residents only see sunlight a few weeks each year
• Developing countries have older cars
– Still use leaded gasoline
• Worst cities in world
– Beijing, China; Mexico City, Mexico; Shanghai, China;
Tehran, Iran; Delhi & Calcutta, India; Dhaka and Gazipur,
Bangladesh

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 Outdoor Air Pollution
• Primary - Released directly from planet’s surface. Dust,
smoke particles, Nitrogen, Carbon etc.
• Secondary - Formed when primary pollutants react or
combine with one another, or basic elements.

26
 Primary Air Pollutants
Carbon Monoxide - Produced when organic materials are
incompletely burned.
• Single largest source is the automobile.
• Not a persistent pollutant.
• Binds to hemoglobin in blood and makes the hemoglobin
less able to carry oxygen.
• Most dangerous in enclosed spaces.
• Cigarette smoking an important source.
Volatile Organic Compounds (VOC)
• Hydrocarbons - Group of organic compounds consisting of carbon
and hydrogen.
– Evaporated from automobile fuel or remnants of fuel
incompletely burned.
– Catalytic converters used to burn exhaust gases more
completely. 27
 Primary Air Pollutants
Particulates—Minute pieces of solid materials dispersed
into the atmosphere (<10 microns).
• Smoke, Asbestos, Dust, Ash
• Can accumulate in lungs and interfere with the ability of
lungs to exchange gases.
Sulfur Dioxide (SO2)—Sulfur and oxygen compound
produced when sulfur-containing fossil fuels are burned.
• Burning coal is primary artificial source
• Volcanoes and hot springs are natural sources
• SO2 is also a precursor to acid rain (a secondary
pollutant)

28
 Primary Air Pollutants
• Nitrogen Oxides (NO, NO2)—Formed when combustion
takes place in the air.
– Automobile exhaust is primary source.
– NOx is also a precursor to acid rain and
photochemical smog (both secondary pollutants) and
is a greenhouse gas

• Ozone (O3)
• PANs (Peroxyacetyl nitrate)
• Aldehydes
• all three formed by interaction between NOx and VOCs.

• Note: - Ozone is a pollutant in the troposphere, but

natural and beneficial in the stratosphere.
29
 Photochemical Smog
• Brown-air smog
• Some primary
pollutants react
under the influence
of sunlight
(photochemical
reaction), including
NOx, O3, PANs
(Peroxyacyl nitrates).
Corrosive, irritating.

30
 Industrial Smog
• Gray-air smog
• From burning coal and oil (particulates, sulfur
dioxide, sulfuric acid).
• London was the smog capitol. In 1952, smog
developed for days, no atmospheric mixing,
4,000 people died.

31
 Regional Outdoor Air Pollution from
Acid Deposition
• Wet deposition • Dry deposition

32
 Acid Deposition and Humans
• Respiratory diseases
• Toxic metal leaching
• Damage to structures, especially containing
calcium carbonate
• Decreased visibility
• Decreased productivity and profitability of
fisheries, forests, and farms
Acid Deposition and Aquatic Systems
• Fish declines
• Aluminum toxicity
• Acid shock
33
 Acid Deposition, Plants, and Soil

• Nutrient
leaching
• Heavy metal
release
• Weakens trees

34
Solutions
to Acid
Deposition

35
 Effects of Air Pollution on
People
• Respiratory diseases
• Asthma
• Lung cancer
• Chronic bronchitis
• Emphysema
• Premature death

36
 Control of Air Pollution
• Industrial Activities
– Scrubbers
– Precipitators
– Filters
• Sulfur Removal
– Switch to low-sulfur fuel.
– Remove sulfur from fuel before use.
– Scrubbing gases emitted from smokestack.

37
What is in your car’s exhaust?
• CO
• CO2
• NOx
• VOCs
• PM
• And can lead to formation of secondary
pollutants

38
Emission Reduction

39
Reducing Motor Vehicle Air Pollution

40
 Indoor Air
Pollution
• Pollutants can be
5-100X greater
than outdoors
• Most common:
– Radon, cigarette
smoke, carbon
monoxide,
nitrogen dioxide,
formaldehyde
pesticides, lead,
cleaning solvents,
ozone, and
asbestos
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 Reducing
Indoor
Air Pollution

42