Transcript Improving Air Quality

Improving Air
Quality
Government and Air Quality
To help people understand and
make decisions related to the
health effects of air quality,
Environment Canada, with the
provinces and territories, has
devised the Air Quality Health
Index (AQHI).
The AQHI is based on the health risks linked to common
air pollutants, including ozone and particulate matter.
The AQHI uses the scale below to indicate the air quality
and its associated high risks.
In Canada, the management of air quality is mainly the
responsibility of the provincial and territorial governments.
There is a federal
environmental law (the Canadian
Environmental Protection Act)
that addresses national
environmental standards.
It commits governments to
meet defined pollution
reduction targets.
As mentioned yesterday, Saskatchewan also has their own
laws in place regulating air pollution.
The Clean Air Act - Protects Saskatchewan's air
quality by regulating emissions that originate in the
province.
Technology, Legislation, and Emissions
Reduction
Laws enacted by governments can require industries to
limit emissions of air pollutants from their manufacturing
plants and from their products.
We will discuss three examples of how emissions have been
reduced from three major sources of air pollution: motor
vehicles, particulate matter and power plants.
Motor Vehicle Emissions
Motor vehicles release more CO, NO2, and VOCs than any
other activity or industry.
Many engineering
changes in cars and
trucks have reduced
the amount of VOCs
that escapes from the
gas tank and
crankcase.
Better fuel efficiency and
specially blended fuels that
produce less CO and
unburned compounds have
also played a role.
Catalytic converters help
reduce emissions.
These devices use materials called catalysts that convert potential
pollutants into harmless substances before they enter the air.
Particulate Matter Emissions
Guidelines are becoming stricter on industrial emissions.
New devices have been developed to reduce the amount of
particulate matter that escape from smokestacks.
The first are: industrial
filters, which trap fine
particles. The filters
act like the bags found
in vacuum cleaners,
allowing air to pass but
stopping particles.
The second is: electrostatic
precipitators, which are more
expensive, but are extremely
effective!
Particulates pick up an
electrostatic charge as they
rise in a smokestack. The
charged particulates are
attracted to a plate that
carries an opposite charge.
Power Plant Emissions
The main pollutants associated with electrical power plants
are particulates, SO2, and NoX.
SO2 emissions require different changes to the way
electricity is produced:
1. Coal burning power plants switch from high-sulfur to lowsulfur coal. This switch alone reduces the amount of SO2
by 66%.
2. Using scrubbers is another alternative. Scrubber are
also very expensive.
The compound calcium oxide (CaO) reacts with SO2 to
form a soil compound, calcium sulfite (CaSO3), which can be
washed away with water.
WHAT CAN WE DO???