Metal

Small metal packaging materials are mostly made from tin and aluminium. Large barrels are made from packaging steel or stainless steel. Metals can be divided into ferrous and non-ferrous metals. Packaging steel and tin are classified as ferrous metals. These packaging materials are generally magnetic and can therefore be separated from a waste stream using a magnet.

Aluminium is a non-ferrous metal. Aluminium packaging materials are non-magnetic, but they can be charged using an electric field (eddy current), which makes it possible to separate them from a waste stream using a special technique. However, this is not possible for composite materials that contain a thin layer of aluminium or vapour-deposited aluminium, because the power generated by the eddy current is too small to effectively separate the aluminium from the waste stream.

 

RAW MATERIALS

- Metals are finite materials. Their scarcity depends on the specific type of metal.
- Because of the mostly excellent recycling options, the metals used for packaging materials are generally widely available.

MASS

The relatively low mass of metal packaging materials reduces their environmental impact:
- Limited amount of material used;
- Limited energy consumption during transport;
- There is a limit to the mass reduction that can be realised.

TYPES OF PACKAGING MATERIALS

- Because of its excellent barrier properties, metal is suitable for vulnerable products that need a long shelf life.
- To achieve chemical resistance, specific treatment processes and coatings can be applied.
- Metals are also used for:
- canned goods, beverage cans, paint and oil cans made of tinned steel or – an increasingly popular option – plastic-coated steel;
- aluminium trays;
- gas and liquids in aerosols;
- bulk goods in barrels; and
- promotional packaging materials.

PROCESS EFFICIENCY

- The production of the packaging materials and the packaging process are usually two separate processes. This means that the metal packaging materials must be transported to the packager while empty.
- As with glass, this has a major environmental impact on the transport and storage of empty packaging materials, depending on the distance that the empty packaging materials must travel.

PROTECTION

- Metal has excellent barrier properties and chemical resistance.
- The mechanical protection requires extra attention because of the risk of mechanical damage such as dents.

REUSE

- Metal packaging materials are often eminently suitable for reuse. Metal cans are frequently reused in households. There are also metal storage cans for coffee that are collected and reused up to 120 times (for example Santas coffee).
- Other examples of reusable packaging materials include beer kegs, gas bottles, and oil barrels. A deposit scheme is commonly used for these materials.

COLLECTION

Metal packaging materials are collected in two ways: as part of the residual waste stream or via separate collection together with plastic and beverage cartons (commonly known as PMD).
Metal collected in the residual waste stream is sent to a waste incineration facility. Any metal left after the incineration process is separated from the bottom ashes.
Many businesses sign a contract with a waste collector for metal packaging materials for which a return system does not exist.

SORTING AND RECYCLING

- Ferrous and non-ferrous metals are generally easy to separate from waste streams due to their magnetic properties. In fact, it is becoming easier to recover metals from the bottom ashes left after the incineration of residual waste. Only thin-walled applications and vapour-deposited metals cannot be recovered on a large scale yet.
- Metals are highly suitable for recycling. In most cases, they can be recycled ad infinitum. The recycled material can be used for food packaging as well.

USE OF THE RECYCLED MATERIAL

Metal packaging materials can be used for a wide range of applications after recycling. Recycled metals are not necessarily used to produce new packaging materials. They can be used for all types of metal products, especially steel.
For aluminium, the possible applications depend on the aluminium’s alloy.

CHALLENGES IN THE CHAIN

Metal packaging materials can be exceptionally thin, which can make their recovery difficult. Examples include thin-walled aluminium beverage cans and vapour-deposited aluminium that cannot (yet) be recovered from the bottom ash after incineration.