Environmental Engineering Reference
In-Depth Information
automobiles, trucks, and other vehicles, these mobile sources still contribute significantly to
air pollution.
Perhaps the greatest long-term threat to the environment is the steadily increasing concentration
of carbon dioxide in the atmosphere, for the most part a consequence of the combustion of fossil
fuel. CO
2
and some other so-called greenhouse gases may trap the outgoing thermal radiation from
the earth, thereby causing global warming and other climate changes.
In this chapter we deal with the environmental problems caused by the use of fossil fuels. The
chapter is divided into sections on air pollution (with separate subsections on photo-oxidants and
acid deposition), water pollution, and land pollution. The large looming problem of global climate
change associated with CO
2
and other greenhouse gas emissions will be addressed in the following
chapter.
9.2
AIR POLLUTION
Among the environmental effects of fossil fuel use, those that impair air quality are arguably the
most problematic. Most emissions into the atmosphere are a consequence of fossil fuel
combustion
.
We are all familiar with the visible smoke that emanates from smoke stacks, fireplaces, and diesel
truck exhaust pipes. But in addition to the visible smoke, a plethora of pollutants are emitted
from combustion “sources” in an invisible form. Emissions may occur also during the extraction,
transport, refining, and storage phases of fossil fuel usage. Examples are fugitive coal dust emissions
from coal piles at the mine mouth or storage areas at power plants; evaporative emissions from
crude and refined oil storage tanks, as well as from oil and gasoline spills; evaporative emissions
from gasoline tanks on board vehicles and during refueling; natural gas leaks from storage tanks
and pipelines; fugitive dust from ash piles; and so on.
Air pollution is not a recent phenomenon. Air pollution episodes due to open-fire coal burning
were observed in medieval and renaissance England. In 1272, King Edward I issued a decree
banning the use of “sea coal,” coal that was mined from shallow sea beds and was burned wet
in open kilns and iron baskets. In 1661, John Evelyn, a founding member of the Royal Society,
wrote “
...
as I was walking in your Majesties Palace at Whitehall
...
a presumptuous Smoake
...
did so invade the Court
...
[that] men could hardly discern one another from the Clowd
....
And
what is all this, but that Hellish and dismall Clowd of Sea-Coal
...
[an] impure and thick Mist,
accompanied with a fuliginous and filthy vapour
”
1
The association of air pollution episodes with human mortality and morbidity was recognized
in the late nineteenth and early twentieth century. In 1873, in London, during a typical “fog”
episode, 268 deaths occurred in excess of what would be normally expected in that period. In
1930, in the heavily industrialized Meuse Valley, Belgium, during a three-day pollution episode,
60 people died and hundreds were hospitalized. In 1948, during a four-day episode, in Donora,
Pennsylvania, where several steel mills and chemical factories are located, 20 persons died and
about one-half of the 14,000 inhabitants got sick. A terrible fog episode occurred again in London
from 5 to 8 December 1952. The excess death numbered 4000! Most of the dead people had a
....
1
Quoted from Cooper, C. D., and F. C. Alley, 1994.
Air Pollution Control: a Design Approach,
2nd edition.
Prospect Heights: Waveland Press.
