About half
of all lead produced each year comes from recycled material, which means that
lead has one of the highest recycling rates of all materials in common use
today. In 2008, worldwide production of lead exceeded 8 million tonnes.
The largest
producers of mined lead are China, Australia, and the USA, whereas the largest
producers of recycled lead are the USA, China, and Germany. China alone
accounts for about 60 percent of all lead production.
The most
economically important lead ore is called galena. Galena contains lead sulfide
(PbS), as well as zinc and silver, all of which can be extracted and refined to
produce pure metals. Other ores that are mined for lead include anglesite and
cerussite.
A large
proportion (about 90 percent) of all lead is used in lead-acid batteries, lead
sheets and other metal applications that are recyclable. As a result, about 5
million tonnes of lead (or 60 percent of all production) were produced from
recycled materials in 2009.
Applications
- The primary
application for lead continues to be in lead-acid batteries, which account for
approximately 80 percent of the metal's use.
- Lead acid batteries are ideal for all types of vehicles because of their relatively large power-to-weight ratio, which allows them to supply the high surge currents required by automobile starter motors.
- Advances in lead-acid battery discharge/charge cycles have also made these viable as power storage cells at emergency power stations for hospitals and computer installations, as well as in alarm systems. They are also used as storage cells for renewable energy sources, such as wind turbines and solar cells.
- Although pure lead is very reactive, lead compounds, such as lead oxide, can be very stable, making them suitable as ingredients in corrosion resistant coating for iron and steel. Lead coatings are used to protect ship hulls, while lead stabilizers and sheathings are used to protect underwater power and communication cables.
- Lead alloys are still used in some bullets and, due to the metal's low melting point, in metal solders. Lead glass has special applications in camera lenses and optical instruments, while lead crystal, which contains up to 36 percent lead, is used to create decorative pieces. Other lead compounds are still used in some paint pigments, as well as matches and fireworks.
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