Scrap metals are the raw material for Worldwide Metals recycling industry. Over 400 million tonnes of metal is recycled each year all over the world.It is a £4.5billion UK industry, processing ferrous and non ferrous metal scrap into vital secondary raw material for the smelting of new metals. The UK is in top five metal scrap exporting countries in the world.

Uses:

Scrap metal has the following uses:

Steel - Recycling is an integral part of the steel-making process because the use of steel scrap lowers the total cost of producing new steel. Steel mills use one of two types of furnaces to make new steel. Both furnaces recycle old steel products into new steel, but each is used to create different products for varied applications.
The first, the basic oxygen furnace, uses a minimum of 25% steel scrap to make new steel. This furnace produces the steel used in flat-rolled steel products, like cans, appliances and automobiles.
The other type of steel-making furnace, the electric arc furnace, melts virtually 100% steel scrap to make new steel. This steel is used primarily to make products that are long shapes, like steel plate, rebar and structural beams.

Iron foundries also melt steel scrap to make new iron products; which contain about 75% scrap. These cast products include engine blocks and machinery parts.

Iron - Iron from the blast furnace contains about 5% carbon which comes from the coke inside the furnace. It is cast into moulds called pigs and the iron is called cast iron or pig iron.
Molten scrap iron and molten scrap steel are mixed with molten iron from the blast furnace in a converter. This is the stage when scrap iron and steel are recycled. Carbon is removed from the mixture by bubbling pure oxygen through it. The oxygen reacts with the carbon to form carbon dioxide. Other non-metals in the mixture react with the oxygen to form acidic oxides. Calcium carbonate is then added to remove the acidic oxides. These reactions produce pure iron which is called wrought iron. The wrought iron can then be used to produce new products.

Aluminium - Recycling is part of the natural life cycle of aluminium. Because the metal can be simply re-melted - using only around 5% of the energy used in primary production - and can be recycled time and again without loss of quality, aluminium retains a high scrap value, which drives high recycling rates in each end-use sector.Aluminium production uses a single production method - the Hall-Héroult Process. But virgin raw materials require temperatures of around 900 C, whilst scrap aluminium melts at around 660 C.

• Remelt: Collected, sorted and sometimes shredded and de-coated aluminium is recycled through a simple remelt process. Alloy composition is checked and the molten metal further cleaned before it is ready for casting into ingots. Ingots are cast from molten aluminium to the specification required. Drinks cans are generally recycled into new drinks cans. Foil is recycled with other aluminium scraps into alloys for casting items such as engine components, window frames and door handles
• Rolling: One of the most important ways for converting aluminium for product use. The rolling process reduces the large ingots into gauges of aluminium from 250mm thick right down to 0.006mm. Rolling imparts flexibility and strength to the aluminium from what was a relatively brittle structure.
• Packaging Manufacturers: Rolled aluminium is made into a variety of packages ready for food and drinks companies to use. These include drinks cans, food trays, pie cases, dairy lids and chocolate wrappers.
• Food and Drinks Companies: Aluminium is used for packaging for many reasons: strength, lightness, temperature tolerance and barrier properties. Excellent supply chain handling characteristics and a strong environmental profile are other key factors.
• Retailers: Aluminium strength and lightness ensure goods arrive in the shops safely and with low supply chain and transportation costs. The metallic brilliance of aluminium attracts customers and is associated with quality products.

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Brass - The recycling of brass scrap is a basic essential of the economics of the industry. Brass for extrusion and hot stamping is normally made from a basic melt of scrap of similar composition adjusted by the addition of virgin copper or zinc as required to meet the specification before pouring. The use of brass scrap bought at a significantly lower price than the metal mixture price means that the cost of the fabricated brass is considerably less than it might otherwise be.
The presence in brass of some other elements such as lead is often required to improve machinability so such scrap is frequently acceptable. Besides the common free-machining brasses, there are many others made for special purposes with properties modified to give extra strength, hardness, corrosion resistance or other attributes, so strict segregation of scrap is essential.
Brass swarf arising from machining operations can be economically remelted but should be substantially free from excess lubricant, especially those including organic compounds that cause unacceptable fume during remelting.
When brass is remelted, there is usually some evolution of the more volatile zinc. This is made up in the melt to bring it back within specification. The zinc is evolved as oxide that is drawn off and trapped in a baghouse and recycled for the manufacture of other products.
Brass to be made in to sheet, strip or wire form must be free of harmful impurities in order to retain ductility when cold. It can then be rolled, drawn, deep drawn, swaged, riveted, spun or otherwise cold formed. It is normal therefore to make it substantially from virgin copper and zinc, together with process scrap arising from processing that has been kept clean, carefully segregated and identified.

Copper –Copper scrap is used by both primary and secondary producers, where processing methods include blast furnace, reverberatory furnace or electric arc furnace. In the latter, around 75-80 per cent raw material is scrap copper.
Good quality high conductivity copper can be recycled by simple melting and check analysis before casting, either to finished shape or for subsequent fabrication. However, this normally only applies to process scrap arising within a copper works. Where copper has been contaminated and it is required to re-refine it, it is normally remelted and cast to anode shape so that it can be electrolytically refined.
For non-electrical purposes, copper is also used to make large quantities of plumbing tube, roofing sheet and heat exchangers. High electrical conductivity is not mandatory and other quality requirements are not so onerous. Secondary copper can be used for the manufacture of these materials, though still within stipulated quality limits for impurities.

Metals recycling protects the environment and saves energy. Using secondary raw materials means less use of natural resources which would otherwise be needed to make new metal compounds – such as iron ore in steelmaking; nickel in stainless steel; or alumina and bauxite in aluminium smelting. There are also considerable savings in energy, and reduced CO2 emissions, in production methods using recycled materials:

In 2005, 13 million tonnes of metal was recycled in the UK. Around 40% of this was used in the UK, and the remaining 60% exported worldwide: the UK produces considerably more scrap than is required for domestic markets.