L-33Vehicular pollution

Air Pollution and Control

(Elective -I)

• Vehicle emissions control is the study and practice of reducing the motor vehicle emissions -- emissions produced by motor vehicles, especially internal combustion engines.

• Emissions of many air pollutants have been shown to have variety of negative effects on public health and the natural environment. Emissions that are principal pollutants of concern include:

• The Combustion Process

• Gasoline and diesel fuels are mixtures of hydrocarbons, compounds which contain hydrogen and carbon atoms. In a "perfect" engine, oxygen in the air would convert all the hydrogen in the fuel to water and all the carbon in the fuel to carbon dioxide. Nitrogen in the air would remain unaffected. In reality, the combustion process cannot be "perfect," and automotive engines emit several types of pollutants.

• "Perfect" Combustion:

• FUEL (hydrocarbons) + AIR (oxygen and nitrogen) ==>> CARBON DIOXIDE + water + unaffected nitrogen

• Typical Engine Combustion:

• FUEL + AIR ==>> UNBURNED HYDROCARBONS + NITROGEN OXIDES + CARBON MONOXIDE + CARBON DIOXIDE + water

Typical Emissions from a Car

•• Exhaust Pollutants Exhaust Pollutants • HYDROCARBONS: Hydrocarbon emissions

result when fuel molecules in the engine do not burn or burn only partially.

• Hydrocarbons react in the presence of nitrogen oxides and sunlight to form ground-level ozone, a major component of smog. Ozone irritates the eyes, damages the lungs, and aggravates respiratory problems. It is our most widespread and intractable urban air pollution problem. A number of exhaust hydrocarbons are also toxic, with the potential to cause cancer.

• NITROGEN OXIDES (NOx): Under the high pressure and temperature conditions in an engine, nitrogen and oxygen atoms in the air react to form various nitrogen oxides, collectively known as NOx. Nitrogen oxides, like hydrocarbons, are precursors to the formation of ozone. They also contribute to the formation of acid rain.

• CARBON MONOXIDE (CO): Carbon monoxide is a product of incomplete combustion and occurs when carbon in the fuel is partially oxidized rather than fully oxidized to carbon dioxide (CO2). Carbon monoxide reduces the flow of oxygen in the bloodstream and is particularly dangerous to persons with heart disease.

• CARBON DIOXIDE (CO2): In recent years, the EPA has started to view carbon dioxide, a product of "perfect" combustion, as a pollution concern. Carbon dioxide does not directly impair human health, but it is a "greenhouse gas" that traps the earth's heat and contributes to the potential for global warming.

• Particulate matter – Soot or smoke made up of particles in the micrometre size range: Particulate matter causes negative health effects, including but not limited to respiratory disease.

• Sulphur oxide (SOx) - A general term for oxides of sulphur, which are emitted from motor vehicles burning fuel containing a high concentration of sulphur.

Control techniques

1. AIR TO FUEL RATIO• A/F ratio is important engine variable to

control auto exhausts.

• Leaner mixture reduces HC and CO but increases NOx

• Richer mixture increases HC but reduces NOx

Exhaust Gasses

14.7 – 1 AFRRicher Leaner

H-C and CO increases

NOxdecreases

NOxincreases

H-C and CO decreases

2. Catalytic Converters

HC and COCO2 H2O

Catalytic Converter

Engine

Exhaust Flow from engine through converter

Catalytic converter

• The catalytic converter is a device placed in the exhaust pipe, which converts hydrocarbons, carbon monoxide, and NOx

into less harmful gases by using a combination of platinum, palladium and rhodium as catalysts.

• Reduces emissions.

• Increases fuel efficiency.

3. PUC i.e. Emission Testing

• Pollution Under Control (PUC)

-Under Rule 115 (7) of Central Motor Vehicle Rules

(CMVR), 1989, motor vehicles are required to carry

PUC Certificate to be given by an agency

authorised for this purpose by State Govt.

• Measurement of emissions from petrol vehicle is

done by gas analyzer and in case of diesel vehicle

emission are measured by smoke meters. There is

a list of approved vendors and models of PUC

equipment which is compiled and circulated by

ARAI, Pune.

•PUC

-To ensure that the in-use vehicles are maintained well and less emitting

•Gasoline vehicles are tested for Idle CO emission

•Diesel vehicles are tested for Free acceleration smoke

4. Cleaner fuels• The fuels used these days in cars has

many compounds, which can cause impurities. You will have to keep your car clean and try to remove all the sulphur from the fuel. You must use fuels like ethanol, methanol and hydrogen, because all these fuels have a clean burning. These fuels have low carbon content as compared to gasoline and diesel. Use unleaded fuels

5. Reduce Driving• Many of us are still dependent on the fossil fuels

and the numbers of cars that are on the road are increasing everyday. If you take some measures to drive less, then it can help in curbing the vehicular pollution and protect some of our natural resources.

• You can maintain your vehicle in a proper manner, so that there is no harmful emission coming from your car. Drive as little as possible, use the public transport or you can walk towards your destination if it is close by.

6. Maintenance Tips for Vehicles

1. Drive moderately; avoid speeding your vehicle and stopping frequently, because this will help in reducing the fuel use and pollutant emission.

2. Follow simple vehicle maintenance, like regular oil changes, spark plug-replacement and air filter changes. This will increase the life of your vehicle and will improve the fuel economy as well.

3. When you start your vehicle, the engine of the car tends to burn more fuel. However, if you leave your engine idle for more than two minutes, then it burns more fuel than what is required when you start the engine. Switch off engine at signals if period is more than 1.5 mins.

4. During the summer seasons, park your car in a shaded and cooler area, this will minimize the evaporation of the fuel.

7. Use of Electric cars

• Use of Zero emission vehicles such as ‘hybrid cars’ or ‘electric cars’(Battery operated)

8. Awareness and legislation

• Creating awareness in public will help in reducing air pollution problem.

• At the same time strict legislative measure to curb excessive emissions can also be adopted.

What are the steps taken to control vehicular pollution? By CPCB

• The following steps are taken:

• Establishment of Ambient Air Quality Monitoring throughout India

• Notification of Ambient Air Quality Standards under Environment (Protection) Act.

• Notification of vehicular emission norms for year 1990-91,1996, 1998, 2000, 2001

• Improving fuel quality by phasing out lead from gasoline, reducing diesel sulphur, reducing gasoline benzene, and etc.

• Introduction of alternate fuelled vehicles like CNG/LPG.

• Improvement of public transport system.

• Phasing out of grossly polluting commercial vehicles.

• Public awareness & campaigns.

Air Pollution Act

• In the Constitution of India it is clearly stated that it is the duty of the state to ‘protect and improve the environment and to safeguard the forests and wildlife of the country’.

• It imposes a duty on every citizen ‘to protect and improve the natural environment including forests, lakes, rivers, and wildlife’.

What are the laws enforced by of the Pollution Control Boards ?

• The Central and State Pollution Control Boards were set up for enforcement of the Water (Prevention & Control of Pollution) Act, 1974. Over the years, the Boards have been assigned additional responsibilities which include the following :

• Water (Prevention & Control of Pollution) Cess Act, 1977.

• Air (Prevention & Control of Pollution) Act, 1981

• Environment (Protection) Act, 1986 and Rules made thereunder

• Hazardous Waste (Management & Handling) Rules1989.

• Manufacture, storage and Import of Hazardous Chemicals Rules, 1989

• Bio-medical Waste (Management & Handling) Rules, 1998

• Municipal Solid Waste (Management & Handling) Rules, 2000.

• Plastics wastes Rules, 1999 o Coastal Regulation Zone Rules, 1991

• Public Liability Insurance Act, 1991

Background

• Water act was introduced in 1974.

• Under above act aspects of air pollution were not covered.

• Therefore The Air (Prevention and control) pollution act, 1981 was introduced.

Definitions• Air pollution means any solid, liquid or

gaseous substance present in the atmosphere in such concentration as may be or tend to be injurious to human beings or living organisms/creatures or plants or property or environment

Constitution of boards

• A state board under the act consists of following 17 members – all nominated by the state government

1. A full time or part time chairman

2. Five official members to represent the government

3. Five persons representing the local authority

4. Three non official members from NGOs

5. Two persons representing companies/corporations owned or managed by the state government

6. A full time member secretary

• Functions of Central Pollution Control Board :

• Advise the Central Government on matters relating to pollution;

• Coordinate the activities of the State Boards;

• Provide Technical assistance to the State Boards, carry out and sponsor investigations and research relating to control of pollution;

• Plan and organize training of personnel;

• Collect, compile and publish technical and statistical data, prepare manuals and code of conduct.

• To lay down standards;

• To plan nation wide programme for pollution control.

• Functions of the State Pollution Control Boards:

• To advise the State Government on matter relating to pollution and on siting of industries

• To plan programme for pollution control;

• To collect and disseminate information;

• To carry our inspection;

• To lay down effluent and emission standards;

• To issue consent to industries and other activities for compliance of prescribed emission and effluent standards,

Penalties and procedures• A person found guilty under this act may get

imprisonment not less than 1.5 yrs but which may be extended up to 6 yrs and additional fine up to Rs. 5000/- for every day during which failure continues.

• If offence is committed by a company then person responsible for conduct of company will be held responsible and held guilty

Theory QuestionsQ1. Write short notes on

1. The Air (Prevention and control of pollution) Act, 1981 (Dec 2009, 6 marks)

2. Pollution due to automobiles. (May 2009,Dec 2009, 6 marks)

3. Control of automobile exhaust emissions. (Dec 2010,Dec 2010(old), 6 marks)

4. Air pollution control act (Nov 2008, May 2009, Dec 2010, 6 marks) (Ans – Introduction, definition of AP, constitution of boards, functions and penalties)