Subject: Carbon and coal energy
Introduction
Information about carbon
Carbon is a chemical element with symbol C and atomic number 6. Carbon is one of
the few elements known since antiquity. Carbon is one of the most abundant elements in the
Earth's crust, and the fourth most abundant element in the universe by
mass after hydrogen, helium, and oxygen. Carbon is the second most abundant element in
the human body by mass (about 18.5%).
Information about carbon
Coal is made largely of carbon but also features other elements such as hydrogen, oxygen,
sulfur and nitrogen. Coal starts off as plant matter at the bottom of water. It is eventually
covered and deeply buried by sediments where over time metamorphosis (a change in form)
takes place. Coal is a readily combustible rock formed from compaction and indurations of
variously altered plant remains similar to those in peat. After a considerable amount of time,
heat, and burial pressure, it is metamorphosed from peat to brown coal and then into hard
coal.
Coal is classified into three main ranks:
a) Hard Coal: contains over 78% of carbon
b) Brown Coal (Lignite): contains 60 – 78% of carbon
c) Peat: contains ca. 30 % of carbon
Coal has long been burned to create electricity and heat. The use of coal is increasing every
year, in 2006 the world consumed over 6,000,000,000,000 kilograms of coal! Coal is the
world’s largest source of energy for the production of electricity. Coal is converted
to electricity by being burned in a furnace with a boiler. The boiler water is heated until it
becomes steam, with the steam then spinning turbines and generators to create the
electricity. Nearly 70% of China’s electricity comes from coal. In total, coal produces
around 40% of the world’s electricity.
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