The scrapping of cars takes into consideration not only the clean separation and expert disposal of all parts and liquids, but also their re-use. The law states exact percentage rates for the years to come, of which scrap car parts should be re-intergrated into the raw material cycle. The ultimate aim is that, from a mid-range passenger car, no more than the contents of an 80-litre-garbage bin must be disposed of. The re-cycling of waste materials means big cash savings, e.g., today already 20% of the cost of metal, and at least 3% of the cost of energy, and, the tendency is rising. Here a small table of the highest re-cycling rates with percentages between 88 and 72:
Generally speaking, the use of Aluminium in the production of a new vehicle is only justifiable, because of the high energy consumption needed for production, if the material is provided through re-cycling.
In the process of scrapping, all the fluids in the vehicle are, first of all, either sucked out from above, or drained out from below. One separates, e.g., brake fluid and oils and passes them on for almost one hundred percent re-processing. The petrol tank is drilled into (very carefully!) at the lowest point, and after possibly filtering the removed fuel, it can be used directly. Special attention must be given to the shock absorbers which contain, as everybody knows, shock-absorber oil. It is legally required that a record be kept of all fluids in the vehicle, with the possible exception of the windscreen cleaning fluid.
Before any major forces are used on the car to be scrapped, all parts which may perhaps be dangerous must be neutralised. Especially all the air bags which must be detonated under carefully controlled conditions. Gas-filled struts, e.g., for the tailgate must be put out of action by drilling holes in them. This is valid of course also for devices with a consistent air- or nitrogen volume, e.g., air suspension or certain ABS equipment. Some parts bring extra money e.g. a catalyst. Which is cut out with a hydraulic shear from the exhaust tract.
The wheels are easily removable and are further used either directly, or separately exploited by rim and tire. Whatever happens to the rest, depends on the storage capacity of the scrap yard. Either a lot of still useful parts are dismantled, listed and stored, or less is dismantled and the vehicles are stacked outdoors and are available perhaps for used parts buyers who do their own dismantling. This, particularly concerns car body parts. A well organised scrap yard has an extensive knowledge of the spare-parts market and often sells used parts, and, after specially marking them, sometimes even with a return guarantee. It is also important to dismantle easily accessible synthetic parts and to dispose of them separately, according to their category.
The rest of the scrap car is compacted, in special companies using heavy-duty presses, to stackable packages like the former Mercedes Benz 190 in the above figure. Afterwards the package is chopped up into very small pieces by fast rotating, extremely powerful impact machines.
Various separation possibilities:
- Light-weight substances, e.g., the interior lining are filtered out specifically by blowing with air. Afterwards these can be burnt for energy production. However, small quantities of very toxic pollutants can also be produced (e.g., dust) which must be carefully shielded and transported to where it can be deposited in disused mines.
- Strong magnets or eddy-current-producers filter out more than 90% of the metals. These still make up by far the biggest part of a car. In Germany the steel production relies almost exclusively on scrap metal.
- Various types of aluminium are colour-marked by laser-supported spectroscopes and are then separated. Aluminium is therefore, also being used more and more in the motor-car construction because it supports the economical cycle. The direct production from Bauxite requires far more energy.
- The remainder, e.g., glass can also be melted and re-used.
|For disposal or recycling, it also depends on the ecological use of energy (minimum energy). This may include the energy generation from emission controlled incineration. Generally the principle applies: recycling before disposal.|
According to the European regulation for 'end of life vehicles', car manufacturers must take back their obsolete cars. Maybe the labour-, energy and raw materials market will develop in such a way that the complete dismantling of these vehicles would be worthwhile again. Even now a great number of parts (e.g., synthetics) in the vehicle are marked. They can then be used even more directly in the production process. 02/12