Coolers, refrigerators and freezers

Coolers

The collection and processing category for coolers, refrigerators and freezers (cooling devices) includes the following appliances:

• refrigerators,
• freezers,
• chest freezers,
• combined refrigerator-freezer units,
• air conditioners and
• heat pumps.

Recovering raw materials and removing hazardous substances

Refrigerators and freezers are primarily made up of ferrous and non-ferrous metals, plastics, and PUR foam.

The following table and graph present the approximate quantity of raw materials recovered each year in the processing of refrigerators and freezers, and the proportion of different specific materials that are recovered.

Materials recovered from coolers, refrigerators and freezers (2022 data)

Breakdown of coolers, refrigerators and freezers by percentage of total mass (2022)

Hazardous substance removal

Mercury switches and condensers are removed from refrigerators and coolers during the hazardous-substance removal process. The main emphasis is on separately capturing CFCs and HCs from the coolants and propellants, which are later destroyed through thermal processing. Two stages are involved:

Stage 1 – Extracting coolant from the cooling circuit

Recycling of coolers UFH, Kematen (© UFH RE-cycling GmbH, 2018)

In the first stage of the process, capacitors, mercury switches and glass plates are removed. The CFC/HC oil mixture is then sucked out of the cooling circuit, and the compressor is removed. The compressor consists mainly of ferrous metals, and is reused for secondary raw materials.

In a further step, CFCs and HCs are separated out of the compressor fluid through a cryocondensation process, or through a special heat and pressure process.

Once the CFCs and HCs have been removed, the compressor fluid can be reused. CFCs are “cracked” in a high-temperature furnace, i.e.
broken down into hydrofluoric and hydrochloric acids, thereby
rendering them harmless. HCs are processed thermally.

The first stage of recycling refrigerators and freezers is handled by a small number of facilities in Austria, e.g. UFH RE-cycling GmbH in Kematen (www.ufhrecycling.at) and Energie AG Oberösterreich Umwelt Service GmbH in Timelkam.

Stage 2 – Final processing

Recycling of coolers, refrigerators and freezers, Kematen (© UFH RE-recycling GmbH, 2018)

The second step in processing refrigerators and freezers is to recover the CFCs or hydrocarbons (HCs) from the insulating foam – see “Recovering PUR powder”.

An airlock input system is used to direct the appliances through the initial (cross-flow shredder) and final (shredder) breakdown steps. The airlock system is necessary because the second stage of processing takes place in a vacuum so that the CFCs and HCs released during the breakdown process cannot escape into the environment.

Once the CFCs and HCs have been removed, the compressor fluid can be reused. CFCs are “cracked” in a high-temperature furnace, i.e. broken down into hydrofluoric and hydrochloric acids, thereby rendering them harmless. HCs are processed thermally.

The PUR foam which contains CFCs and HCs is separated out, then processed further as described here. What remains is a mix of ferrous metals, non-ferrous metals, and plastics.

The process air, which now contains CFCs/HCs, is extracted and purified through a cryocondensation process, or passed through an activated carbon filter in which the CFCs/HCs are separated out.

The ferrous metals are separated out with a magnetic separator, and non-ferrous metals with a non-ferrous separator, and both types are reused as secondary raw materials. The plastic used for refrigerator and freezer housings is usually polystyrene (PS). As a result, the plastics recovered from recycled refrigerators and freezers can be processed into PS pellets, and almost all of it can be turned into new plastic products (see www.seg-online.de/home/pur/).