Salt Lake City Conference Exhibitors Motor Mania - International ...

A fire melts the ore so that the liquid iron separates from the
rocky, non-iron materials. Coke is used to more efficiently
heat the ore in the smelting process. To understand what
coke is, consider charcoal. Common charcoal is the solid
char leftover when wood is burned. Charcoal is useful
because it ignites quickly and burns hot. Coke is like
charcoal; it is what is left after partially burning coal. It has
the same advantages of charcoal but has much more energy.
Steel is most effectively refined when coke is used in blast
furnaces. So, to fully smelt iron and produce steel with it,
the manufacturer must fire coal to make coke, and then it
must fire the coke to make steel. This is an energy-intensive
process, and in the process, tons of greenhouse gases
and toxic elements and compounds are released into the
atmosphere annually.
Recyclable Materials
Consumers are aware of some recyclable materials but
are less familiar with others. Consumers are familiar with
the recycling of aluminum cans, paper, and some plastics
because many communities encourage consumer recycling
through local programs. It is not unusual for some forms
of glass and steel cans to be accepted in consumer-level
recycling programs. However, entire automobiles can
be recycled for steel and aluminum and, in some cases,
glass and plastics. Building demolitions also produce
structural steel for recycling. Consumers are less aware
of automobile recycling and structural steel recycling.
Lead-acid automobile batteries are also recycled, as are the
components of electronic hardware. The Institute of Scrap
Recycling Industries (2007) reports the following statistics
on recycling volumes in the United States annually.
(Table 1.)
Environmental Implications
Land use is a big issue around the world. Landfills are filling
to capacity at alarming rates, and consumers do not realize
the extent to which municipal waste is dumped directly into
the oceans. Equally alarming is the rate at which municipal
waste is being incinerated, thus adding to the air pollution
problem and global warming. The Environmental Protection
Agency (2007) estimates that in 2005, 79 million tons of
waste was recycled—an increase of 64 million tons since
1980. This figure does not include automobile and structural
steel recycling. Recycling is helping to save landfill space
and reducing, in turn, the amount of ocean dumping and
incineration.
Coal production and consumption around the world and
in the U.S. increases every year. That means that electrical
power plants keep producing more electrical power for uses
related to industry and consumer needs. However, industry’s
use of coal in smelting has not increased at the same rate as
it has for power plants (Energy Information Administration,
2007). This is attributed to recycling metals (Institute of
Scrap Recycling Industries, 2007). Each year power plants
dump tons of pollutants into the air. Certainly many tons of
greenhouse gasses are released as the burning of coal creates
chemical reactions, but many people do not understand
that many toxic elements and compounds naturally occur in
coal that are also simply released into the atmosphere when
coal is burned. Mercury is an example of such an element.
Could one imagine being exposed to mercury? It is highly
toxic to humans and animals, yet coal-fired power plants
dump literally tons of mercury on the environment every
year. Table 2 shows emissions from coal-fired electrical
generators. Many industries use tons of coal each year for
Quantity of Recycled Material
Type of Material
81.4 million tons* iron, steel
53.5 million tons paper
4.5 million tons aluminum
3.5 million tons glass
1.8 million tons copper
1.4 million tons stainless steel
1.4 million tons lead
957.5 thousand tons plastic
459 thousand tons zinc
111 million automobile tires
*ton = 2,000 lbs. Ton here is not to be confused with a metric ton or a long ton, which are shipping weights. A 2,000 pound
ton is also referred to as a short ton.
Table 1. This table shows the tonnage of recycling per year for each type of material. In one year, more than 150 million tons of materials
were recycled into new products instead of ending up in landfills.
14 • The Technology Teacher • February 2008