Eco-Design Guidelines:

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Materials

Which environmental impacts do the materials cause?

Materials consist of resources and production of them needs energy. For metals, the resources are obvious, for plastics, the resources are oil and natural gas. Some materials, e.g. copper produce a lot of waste during extraction, because the ores only consist of a small amount of copper. Besides, materials need a variety of chemicals and can lead to emissions of more or less toxic substances.


Energy consumption

All materials need energy to be produced. This processing energy - needed for extraction, refining and further processing of virgin resources into 'ready-to-use' materials - will typically be electrical or thermal. Further, as mentioned above, some materials like plastics are synthesised from energy sources like gas or oil and thereby have an inherent energy content.

The total energy input to a material is the sum of processing and inherent energy. In order to add these energies, a common unit - primary energy - is needed. Primary energy is the combustion values of the fuels used to generate the processing energy or the combustion value of the gas or oil applied for e.g. plastics synthesis. This implies that e.g. electricity energy has to be multiplied by a factor corresponding reciprocally to the efficiency of the electricity generation system. This factor is in the order of two to three.

Some of the inherent energy in plastics may be recovered by incineration. This energy corresponds to the combustion value of the material. It should be remembered that this energy can not be recovered 100%, as it has to be corrected by the efficiency of the incineration system!


Table of primary energy input for production/combustion of materials




Limited resources

Resources can be found in the earth but no matter what we do, the amount of resources is limited. Use of fossil fuels is an irreversible process - once they have been used, they have gone. For metals, the resources do not disappear, but if we don't take care of them, we end up diluting them to such an extent in the waste streams that re-extraction of them will be very energy intensive - and for that we need fossil fuels.



A way of describing the scarcity of resources is by defining the "World Reserves Life Index" (WRLI). It is based on the amount of reserves (the amount of a resource that is economically profitable to extract) and the consumption of resources. WRLI is defined as the reserve divided by the yearly consumption of the resource. It gives the number of years we have left of a given resource, assuming constant reserves and constant consumption.



If the materials of your product contain scarce resources, try to find alternatives containing less scarce resources.





Reduce the environmental impacts: Avoid mixing of materials

For the recycling industry, there can be different reasons to disassemble the equipment:

Mixing of materials can result in problems with an environmentally optimal recycling during disposal. This may result in:

For metals the occurrence of certain impurities can be detrimental for the recycling of metals.

In other cases the problem is that only a certain concentration of an impurity can be tolerated.

Metal

Elements which are detrimental to recycling

Elements which reduce the recycling value of the scrap
Copper
  • Mercury
  • Beryllium
    • Arsenic
    • Antimony
    • Nickel
    • Bismuth
    • Aluminium
    Aluminium
    • Copper
    • Iron
      • Silicon
      Iron
      • Copper
      • Tin
      • Zinc



      If your product contains undesirable combinations of metals, try to find alternative solutions or design your product in a way that eases separation of incompatible combinations.

      One example is coils and transformers containing copper and iron. These metals are both easily recycled, but the best value is achieved when they are 'pure'. So for the larger types of these components, they should, whenever possible without sacrificing electrical efficiency, be made separable in their pure material fractions.


      Reduce the environmental impacts: Avoid certain substances

      A place to start your environmental effort is the substances. Be sure that no harmful substances are used or produced during the life cycle of your product.

      According to a new directive from EU (Reduction of Hazardous Substances in Electrical and Electronic Equipment), the following substances should not be contained in electrical and electronic equipment from 1 July 2006 (with certain exceptions):

      Some of these materials or substances are already banned on a national basis.

      Some countries have list of undesired substances. Consider if your product contains some of these, and if it does, can the use of the substance be avoided?


      General checklists for materials



      Recommendations concerning materials in general

      Reason for recommendation
      • Use as few different types of materials as possible
      • Makes it easier to sort materials for recycling
      • Larger amounts of similar materials increase the value of the scrap
      • Reduce the risk of contact with hazardous substances during manufacturing, use and disposal
      • Reduced costs for disposal
      • Avoid using materials characterized as scarce resources
      • Limits the use of scarce resources
      • Use materials which can be recycled in the established recycling systems
      • Reduces consumption of resources and means higher value on disposal
      • Reduce consumption of materials, avoid over-dimensioning
      • Reduces consumption of resources and means higher value on disposal
      • Reduce packaging
      • Label materials
      • Take care that different materials can be separated
      • Compare packaging alternatives by means of LCA
      • Reduces consumption of resources
      • Stimulate recycling
      • Reduce spillage and waste
      • Reduce consumption of resources




      Materials, plastics

      Reasons for recommendations
      • Use as few different types of plastics as possible
      • Makes it easier to sort materials for recycling

      • Larger amounts of similar materials increase the value of the scrap
      • Choose plastics, which:
        • can be recycled, i.e. thermoplastics (e.g. PET, PS) and polyolefines (e.g. HDPE, LDPE and PP)
        • are compatible on recycling
      • Increases possibility of recycling
      • Choose plastics which can be incinerated without emission of hazardous substances

      • Avoid PVC and other halogen containing polymers
      • Since incineration of plastics is the most realistic disposal route

      • In case of fire in electric and electronic equipment, PVC will emit chlorine, and the hydrochloric acid which is formed can result in considerable damage of the installations and other equipment
      • Avoid brominated flame retardants
      • Toxic substances are emitted during incineration at low temperature. Some of the flame retardants are toxic themselves (PBB, PBDE)
      • Plastic parts which are joined together should be made of the same materials
      • Eases recycling
      • Avoid glued labels on the plastic surface
      • Contaminates material on recycling


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