The collection and processing category for coolers, refrigerators and freezers includes the following appliances:
refrigerators, freezers, chest freezers, combined refrigerator-freezer units, air conditioners and heat pumps.
Recovering raw materials
Refrigerators and freezers are primarily made up of ferrous and non-ferrous metals, plastics, and PUR foam. The following table presents the approximate proportion of different materials recovered in the processing of coolers, refrigerators and freezers:
|Refrigerators and freezers||Mass [t]||Proportion [%]|
|Coolants, stage I||30||0,2|
|Cooling circuit oil||59||0,5|
|Propellants, stage II||106||0,8|
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
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 (see UFH RE-cycling GmbH), or through a special heat and pressure process (see www.seg-online.de – Technology/Installation).
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, Saubermacher in Unterpremstetten and Energie AG Oberösterreich in Timelkam.
Stage 2 – Final processing:
The second step in processing refrigerators and freezers is to recover the CFCs or hydrocarbons (HCs) from the insulating foam – see section 5, “Recovering PUR powder”.
An airlock (Keri) 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.
The PUR foam which contains CFCs and HCs is separated out, then processed further as described in section 5. 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 (see UFH RE-cycling GmbH), or passed through an activated carbon filter in which the CFCs/HCs are separated out (see SEG Umwelt-Service GmbH – Installation).
The ferrous metals are separated out with a magnetic separator, and non-ferrous metals with a non-ferrous separator (see section 2.4, Large electrical appliances), and both types are reused for valuable secondary raw materials. The plastic used in 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 SEG Umwelt-Service GmbH – Secondary raw materials).