Waste categories and waste utilization

Waste management in Finland is based on the sorting and recycling of waste. Normally waste is sorted where it is generated so as to maximize the efficiency of recycling. Some types of waste are, however, sorted in waste processing installations. These include electrical waste, metals, plastics and energy waste. Industrial waste sorting methods are generally based on properties of the waste to be sorted such as colour, size, magnetism or density.

The three main categories of waste are utility waste, hazardous waste and mixed waste. Summaries of these follow:

Utility waste can be utilized fully either as raw material or energy. The majority of utility waste generated can be reused as material. Utility waste includes materials such as paper and cardboard, glass, metals, plastics, wood, bio waste and energy waste. Additionally, many materials generated when manufacturing other products can be utilized in other industrial processes. These materials are not classified as waste and are referred to as side products of production.

Hazardous waste contains some material that is hazardous either to humans or the environment so they require special treatment. Hazardous waste can be utilized if it is sorted and treated properly. The majority of hazardous waste generated in Finland is a result of industrial activity. Hazardous waste must be sorted, classified, stored, transported and treated according to existing regulations so as to eliminate any potential hazards.

Mixed waste cannot be utilized either because of economical or technical reasons so it is incinerated or stored in a landfill. As incinerating the waste results in air emissions landfilling is the preferred method of dealing with utility waste. Mixed waste includes materials such as PVC-plastics, cement, soil, laminated glass, construction waste and plaster. If industrial activity results in a significant amount of homogenous waste that cannot be sorted it may still be possible to find another use for it. This is preferable as landfilling is usually the most expensive solution, both for society in general and the environment.

Another important category of waste is electrical waste. Any device that requires electricity to function is classified as electrical waste. Some electrical waste is also classified as hazardous waste. These include refrigerators, freezers, televisions, monitors, laptops and any devices with an inbuilt battery. Although the amount of hazardous waste in a given device is usually small the large amount of other materials used in these devices means that the resulting amount of waste is significant.

Although electrical waste is classified as mixed waste it has to be separated from the waste stream and processed. In the first stage electrical waste is pre-treated manually so as to separate any hazardous waste from the products. After pre-treatment the majority of electrical waste is processed by crushing the waste and separating the different materials (steel, aluminium, magnesium, zinc, lead, copper, silver, gold, platinum, plastics, rubber and glass) by various technical methods.