21-03-2017, 10:17 AM
A blast furnace is a type of metallurgical furnace used for smelting to produce industrial metals, usually iron, but also others such as lead or copper. In a blast furnace, fuel, minerals and limestone continuously flow through the top of the furnace, while a blast of hot air (sometimes with oxygen enrichment) blows into the bottom section of the furnace. Oven through a series of pipes called nozzles, so that chemical reactions occur throughout the furnace as the material moves down. The final products are usually molten metal and slag phases taken from the bottom, and flue gases exiting the top of the furnace. The downward flow of the ore and the flow in contact with an upward flow of flue gases rich in hot carbon monoxide is a counter current and chemical reaction process.
In contrast, air ovens (such as reverberation ovens) are naturally aspirated, usually by the convection of hot gases in a chimney duct. According to this broad definition, bloomeries for iron, houses blowing for tin, and foundry mills for lead would be classified as blast furnaces. However, the term has generally been limited to those used for the smelting of iron ore to produce pig iron, an intermediate material used in the production of iron and commercial steel and wells used in combination with sintered plants in the smelting of Basic metals.
Disadvantages
• Produces carbon monoxide and is very expensive
• Expensive and bad for the environment
• Bad for the environment and dangerous
