PRODUCTION OF METALS

Different metals are produced in different ways, but almost all the metals are found in the form of metal ores (iron ore, copper ore etc). The ore is a mineral consisting of a metal combined with some impurities. In order to produce a metal from some metal ore, we must separate these impurities from the metal. This is done by metallurgy the science – which treats of the methods used to obtain the metals in the free condition from the compounds that occur in nature, i.e. (that is) from the ores. Most commercial metals are produced from their ores by melting process in which any impurities are separated and removed as slag.

Iron is obtained by reducing its ores with carbon. Cast iron and steel are produced in different types of furnaces at metallurgical plants. Cast irons are usually produced in blast furnaces or cupolas. Steels are usually produced in Bessemer converters or open-hearth furnaces. Henry Bessеmer, English inventor and engineer, was born at Charlton on January 19, 1813. He discovered the first process of making inexpensive and plentiful (в больших количествах) steel. The so-called Bessemer process of steelmaking was a great event in the world's economic history. Previously (до этого, прежде) steel had been expensive, made chiefly by the crucible process (в тиглях).

Steel and other metals may also be produced in electrical furnaces. Electrical furnaces are only used in making high-grade tool steel.

The metals from lithium down to manganese are obtained by electrolysis of melted compounds that conduct an electric current.

If we take all the metal produced by the world's metallurgical industry during one year for 100 per cent, we shall see that the production of ferrous metals is about 94 %, the production of copper is about 2 %, zinc about 1.52 %, aluminium 0.6 %, etc. (в английских и американских текстах печатаются: 1.52, which is read «one point five two», 0.6 – is read «zero point six»).

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1) How are metals found in nature?

2) What is an ore?

3) How are metals produced from metal ores?

4) What science is metallurgy?

5) How is iron produced?

6) In what furnaces is cast iron produced?

7) In what furnaces is steel produced?

8) What can you say about the Bessemer process?

9) What kind of steel is produced in electrical furnaces?

10) What metals are produced by electrolysis?

11) Tell some words about the world's metallurgical industry.

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