Many of the food and drink products we buy are packaged in cans made from either aluminium or steel and both of these materials can be recycled after we have finished with them to make either new cans or other products.   

Did you know?

Recycling aluminium uses only around five per cent of the energy and emissions needed to make it from the raw material bauxite.  The metal can be recycled time and time again without loss of properties, so getting the aluminium recycling habit is one of the best things we can do for the environment.

Steel can also be recycled time and time again without loss of quality; by simply recycling our steel cans we can conserve non-renewable fossil fuels, reduce the consumption of energy and the emission of gasses like carbon dioxide into the atmosphere.

Aluminium cans are:

• Shredded, removing any coloured coating
• Melted in a huge furnace
• The molten metal is poured into ingot casts to set.   Each ingot can be made into around 1.5m cans

NB: Aluminium foil is a different alloy and is usually recycled separately with other aluminium scraps to make cast items such as engine components, where it makes a big contribution to making vehicles lighter and more energy efficient.

Steel cans are:

• Put into the furnace where molten iron is added
• Oxygen is then blasted into the furnace which heats up to around 1700 degrees centigrade
• The liquid metal is poured into a mould to form big slabs which are then rolled into coils
• These coils are used to make all sorts of steel products such as bikes, cars, bridges, paperclips or even new food and drink cans.
  

Aluminium is a resource that forms about 8% of the earth’s crust.   It is mined and extracted from bauxite, which contains the compound alumina, in an energy-intensive electrolytic process. Four tonnes of bauxite contains two tonnes of alumina, which yields one tonne of valuable aluminium.   The metal is used in buildings, transport and other industrial applications, as well as packaging.    

Aluminium is the most cost-effective material to recycle, because of the huge energy savings  -  up to 95%.  In addition, all the scraps left over from the aluminium production process can be melted down and used again and again. For this reason, recycling is part of the normal lifecycle for large industrial products - around 75 per cent of all the aluminium ever made is still in circulation.

Recycling 1kg of aluminium saves up to:

• 6kg of bauxite
• 4kg of chemical products
• 14kWh of electricity

Steel is made from one of the earth’s most common natural resources, iron ore, as well as limestone and coal. Mining for these raw materials and the production process involved in making steel have an environmental impact. Not only does the process require large amounts of energy but raw materials are wasted when mining, and the production process also produces waste and emissions.

Steel can be recycled time and time again without loss of quality, so by simply recycling our steel we can:

• Conserve non-renewable fossil fuels
• Reduce the consumption of energy
• Reduce the amount of raw materials being wasted
• Reduce the emission of gasses like carbon dioxide into the atmosphere

Both aluminium and steel are easy to recycle and there are huge environmental benefits for doing this - yet many cans still go to landfill.  If we recycle more cans we can reduce the amount of raw materials needed to produce new products. 

Did you know?

In the UK our steel cans only contain 25% recycled steel, while the cans manufactured in Europe contain 54%.¹

Top tips

• Remember to recycle drinks cans when away from home - i.e. at work, while travelling or at sports and leisure locations. If you can't find a recycling bin - take it home and recycle it later.
• Rinse out food cans with your leftover washing up water before the residue has chance to dry out - it'll take much less effort!
• Check the postcode locator to see what you can recycle in your area.

¹ source: www.scrib.org

Aluminium drinks cans are usually recycled into ingots at a special 'closed-loop' plant in Warrington.  This is the ultimate recycling process for environmental efficiency and used cans are often recycled, made into new cans, filled and put back on the shelf in just six weeks.

Foil and other aluminium is generally recycled with other aluminium scraps such as window frames and road signs, and cast into engine components for vehicles, which makes them lighter and more fuel efficient.

Recycled steel can be found in incredibly diverse variety of products including:

• Bicycle frames
• Pipes
• Train tracks
• Ship hulls
• Cars
• Bridges
• Paperclips
• Food and drinks cans

Steel can be infinitely recycled and because it is such a widely used material, the ranges of possible uses for it are endless.

Domestic waste glass (known as cullet) is easy to recycle. The UK currently recycles around 50% of container glass (like bottles and jars) and whilst this figure has doubled over the last five years it still lags behind other countries i.e.both Switzerland and Finland recycle more than 90% of their glass.

Glass is usually collected in 'bottle banks' at recycling centres or as part of our kerbside collection.  However there is still more we can all do, such as remembering to recycle our clear jars (pasta sauce jars and jam jars) which are often forgotten.

The UK business sector still has a lot of work to do to recycle glass – bars, restaurants and pubs currently throw away 600,000 tonnes of glass every year, with most of it ending up in landfill. 

Did you know?

Recycling two bottles saves enough energy to boil enough water for five cups of tea!

Once glass is collected and taken to be reprocessed, it is:

• Crushed and contaminants removed (mechanised colour sorting is usually undertaken at this stage if required)
• Mixed with the raw materials to colour and/or enhance properties as necessary
• Melted in a furnace
• Moulded or blown into new bottles or jars

The production and use of glass has a number of environmental impacts. New glass is made from four main ingredients: Sand, Soda ash, Limestone and other additives for colour or special treatments.

Although there is no shortage of these raw materials as yet, they all have to be quarried, which can damage the landscape, affect the environment and use more energy.

Glass is 100% recyclable and can be endlessly reprocessed with no loss of quality.  Therefore by simply recycling our glass we can:

• Conserve non-renewable fossil fuels
• Reduce the emission of harmful gasses into the atmosphere.

Did you know?

• The addition of domestic waste glass (known as cullet) to a furnace in the glass manufacturing process, substantially reduces the energy requirement and decreases CO2 emissions. Each tonne of cullet added to the furnace saves 1.2 tonnes of raw materials - decreasing emissions still further.
• New glass takes a lot of energy to make, first in transporting the materials to the furnace and then to heat them to a high temperature. An efficient furnace burns 4 gigajoules (GJ) (unit of energy measuring heat) to melt every tonne of glass – that’s the energy equivalent of burning 250kg of wood.

Although glass is easy to recycle, there is currently some imbalance in the supply of glass for recycling compared to demand for recycled glass for manufacturing.  The prices paid for glass differ, depending on the colour (usually clear, brown, green - blue glass is collected with green glass) which is why we are asked to sort it when we recycle at bottle banks.  Mixed glass has a lower value.

The main problem in the UK is that we do not recycle enough clear glass to keep up with demand.  We produce lots of clear glass, but export a lot of it as spirit bottles so it leaves our supply chain.

By comparison, we import a large amount of green glass but do manage to recycle it – so the green bottles we make in the UK currently contain at least 85% recycled green glass.

The surplus green glass is:

• Exported to make new green bottles
• Used to make fibreglass insulation
• Used in the manufacture of bricks
• Used as filtration media in effluent treatment works

Recycled glass can be used to make a wide range of everyday products and some that are completely unexpected, including:

• New bottles and jars
• ‘Processed sand’ – finely ground glass used in golf course bunkers
• ‘Glassphalt’ for road surfacing

The different types of glass

We use many different types of glass in the UK, but at home we mostly use ‘soda-lime-silica’ glass for containers like bottles and jars. It is important not to mix up the different types of glass as they are re-processed differently.

Different types of glass include:

• Borosilicate glass – used for heat-resistant cooking equipment like Pyrex
• Lead glass – for sparkling decorative glassware
• Glass fibre –for insulation and fibre optic cable

These different types of glass are not widely recycled so do not add these into your kerbside collection container or bottle banks at the recycling centre.

Colour and quality

During the glass manufacturing process, extra raw materials can be added to give the glass a particular colour or special qualities.

The extra raw materials that can be added are:

• Iron for a brown or green colour
• Cobalt for blue
• Alumina for durability
• Boron to improve resistance to heat or cold

Councils use different methods of collecting your recycling. There are kerbside ‘sort’ schemes where recyclables are sorted into their respective materials on the lorry at the kerbside; and co-mingled collections where all your recyclables are put into one compartment on the lorry before being taken to a Materials Recycling Facility (MRF) and sorted. This section is looking at co-mingled collections.

At the MRF, all the mixed recycling is sorted and separated into different types of materials by hand or machine (or both) before being sent to manufacturers who make it into new products.  The machinery, processes and the materials that each MRF can accept do vary, so the video explains the basic principal of the process.

Once materials have been sorted, recycled materials become valuable commodities in the worldwide market.

• The recycling bin, box or sack is emptied into collection vehicle
• The co-mingled materials are taken to a Material Recycling Facility and loaded onto conveyors
• The sorting process begins with the removal of incorrect items such as crisp packets and plastics bags
• A vibrating machines separates the cardboard and paper - different types of paper are sorted by hand and then baled
• The remaining recyclables continue on another conveyor where steel and tins are removed using magnets
• Different types of plastic are identified and separated using optical scanners
• A special kind of magnet is used to sort aluminium cans
• Glass is the remaining material and this drops off the end of the conveyor into a large container (Note - not all MRF's accept glass).

Once separated they are taken for processing at specialist factories.

The biggest problem is when incorrect items are put in the recycling container as they have to be removed by hand. This slows down the process and if these items are missed it can clog or damage the machinery and other equipment.   This is why it is important to know which items you can and can't recycle in your local area. 

To find out what you can recycle at home check out the postcode locator.