Preliminary Hsc Metals Assessment Task
Our Use of Metals 1. Define the terms mineral and ore
Mineral - Any homogeneous, inorganic, solid substance which is naturally occurring.
Ore - Any mineral or combination of a mineral and other substances from which a valuable, useable substance can be obtained (usually metals). 2. Describe the extraction processes, including chemical equations, of copper and aluminium and describe the environmental impact of these extraction processes.
Copper
There are two main methods used to extract copper from its ores. Generally, copper is extracted using the Pyrometallurgical method (also known as smelting), which allows us to separate copper from its sulfide and oxide ores; the other method, called the Hydrometallurgical method (also known as solvent extraction or electrowinning - SX/EW), allows us to also separate copper from its oxide ores. Although this method is more cost effective, it only accounts for a very limited amount of the world’s copper production as its environmental impact is much stronger than that of pyrometallurgy - the by-products of hydrometallurgy contain much higher concentrations of sulfur and metal particulates.
There are four main steps carried out during the pyrometallurgical extraction of copper: 1. Mining, crushing and grinding
The copper ore is dug up from the ground during mining. The mined copper ore (which contains a minimum of 0.5% copper by weight) is placed in a crusher where it is crushed into almond-sized pieces. These pebbles are ground to a talcum powder consistency in a grinding mill to separate the majority of the gangue rock from the copper mineral crystals. Copper oxide ores are moved to leaching tanks where the process of hydrometallurgy begins, while copper sulfide ores continue to the concentration stage. 2. Concentration
The copper sulfide crystals are separated from the rest of the gangue through the froth flotation process, whereby the sulfide ore is placed in a solution of water and pine oil.
Mineral - Any homogeneous, inorganic, solid substance which is naturally occurring.
Ore - Any mineral or combination of a mineral and other substances from which a valuable, useable substance can be obtained (usually metals). 2. Describe the extraction processes, including chemical equations, of copper and aluminium and describe the environmental impact of these extraction processes.
Copper
There are two main methods used to extract copper from its ores. Generally, copper is extracted using the Pyrometallurgical method (also known as smelting), which allows us to separate copper from its sulfide and oxide ores; the other method, called the Hydrometallurgical method (also known as solvent extraction or electrowinning - SX/EW), allows us to also separate copper from its oxide ores. Although this method is more cost effective, it only accounts for a very limited amount of the world’s copper production as its environmental impact is much stronger than that of pyrometallurgy - the by-products of hydrometallurgy contain much higher concentrations of sulfur and metal particulates.
There are four main steps carried out during the pyrometallurgical extraction of copper: 1. Mining, crushing and grinding
The copper ore is dug up from the ground during mining. The mined copper ore (which contains a minimum of 0.5% copper by weight) is placed in a crusher where it is crushed into almond-sized pieces. These pebbles are ground to a talcum powder consistency in a grinding mill to separate the majority of the gangue rock from the copper mineral crystals. Copper oxide ores are moved to leaching tanks where the process of hydrometallurgy begins, while copper sulfide ores continue to the concentration stage. 2. Concentration
The copper sulfide crystals are separated from the rest of the gangue through the froth flotation process, whereby the sulfide ore is placed in a solution of water and pine oil.
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