Environmental Engineering Reference
In-Depth Information
Now the lack of investment in energy-saving measures was coming home to roost.
The economic boom in China and in other countries further boosted the demand for
oil to such an extent that it was diffi cult to meet it. The consequence was that oil
prices kept climbing to new record highs. Even though the oil price has fallen
sharply again due to the current fi nancial crisis, new record prices are expected again
due to the limited supplies available.
Yet there have been some fundamental changes since the beginning of the 1980s.
Energy use has decreased despite rapid and sustained economic growth. The realiza-
tion has set in that energy use and gross national product are not inextricably linked.
It is possible for prosperity to increase even if energy use stagnates or drops.
Nonetheless, the chance to develop true alternatives to oil and use energy-savings
options was missed due to the long period of continuous low oil prices. This is
particularly apparent in the transport sector. Cars became faster, more comfortable,
heavier and had more horsepower, but were only minimally more fuel-effi cient. As
a result of all the talk about climate change and high oil prices, the car manufactur-
ers are now scrambling to incorporate features into their cars that have not been
demanded in decades: fuel effi ciency and low emission of greenhouse gases.
As important as it is as a fuel, that is not the only use for oil, because it is also an
important raw material for the chemical industry. For example, oil is used as a basic
material in the production of plastic chairs, plastic bags, nylon tights, polyester
shirts, shower gels, scents and vitamin pills.
1.1.3 Natural Gas - the Newest Fossil Energy Source
Natural gas is considered to be the cleanest fossil energy source. When natural gas
is burnt, it produces fewer harmful substances and climate-damaging carbon dioxide
than oil or coal.
The base material for the creation of natural gas was usually green plants in the fl at
coastal waters of the tropics. The Northern German lowland plains were part of this
area 300 million years ago. The lack of oxygen in coastal swampland prevented the
organic material from decomposing and so it developed into turf. As time went by,
new layers of sand and clay were deposited on the turf, which during the course of
millions of years turned into brown and bituminous coal. Natural gas then developed
from this due to the high pressure that exists at depths of several kilometres and
temperatures of 120 to 180 °C.
However, natural gas does not consist of a single gas, but rather a mixture of dif-
ferent gases whose composition varies considerably depending on the deposit. The
main component is methane, and the gas also often contains large quantities of
sulphur hydrogen, which is poisonous and even in very small concentrations smells
of rotten eggs. Therefore, natural gas must often fi rst be purifi ed in processing plants
using physiochemical processes. As natural gas deposits usually also contain water,
the gas must be dried to prevent corrosion in the natural gas pipelines.
Natural gas was not seen as a signifi cant energy source until relatively recently. It
was not until the early 1960s that natural gas was promoted and marketed in large
quantities. The reasons for this late use of natural gas compared to coal and oil is
