Washing machines are divided into two main categories, there are top-loading machines and front loading. In addition to the generally higher loading capacity for front loading models, these models differ because the loading door is usually made â€‹â€‹of glass or transparent polymer. Washing machines are also distinguished by the type of weights used, the most common products are equipped with concrete weight while on models generally more upscale, this ballast is cast iron.
The components commonly found on a washing machine are:
– The motor
– The tank
– The weights
– The programmer
– The hydraulic system (drain pump and heater)
– The Drum
– The damper
Composition of a washing machine
Figure 1: Composition of a washing machine with concrete ballast (Eco-Efficiency Analysis of Washing machines – 2004)
Figure 2: Sales of washing machines in thousands of units (source: GIFAM)
Ownership of washing machines is already very high (97% in France in 2015, according to TNS SOFRES). In this context, eco-design is a solution to differentiate a new product against the competition.
Depollution and recycling of the product
Depollution / pre-treatment
Pre-treatment of washing machines is performed to remove the power cable and weights. Indeed, in the case of cast irons weights, it allows to avoid damaging the crusher and get an efficient recovery. For concrete weights, it avoids generating dust which would scatter in other fractions, and allows to recover the concrete.The removal of these parts is done manually.
Treatment / Recycling
After the depollution step, the products are crushed, the main materials recovered for materials recovery are:
– Plastics (ABS, PP)
Proposed improvement plan
The table below provides some ideas to improve the recycling of washing machines. These ideas are from studies on the recycling of some products and difficulties encountered by treatment operators responsible for the treatment of WEEE. These areas for improvement can initiate a deeper reflection from producers. However, each product has its specificities and a number of other constraints to fulfill.
|Encountered difficulties||Impact for recycling||Eco design opportunities|
|The weights are never the same location on the product.||The removal time of pieces is longer.||Facilitate access and removal of weights|
|The weights are sometimes coated with plastic.||Difficulties for identification of parts.||Do not mix recyclables / non-recyclable.|
|The weights are assembled with different types of fasteners.||Obligation to use several different tools.||Reduce the number of different fasteners.
Prefer standard fasteners.
|The capacitors are not at the same place in the product.||Dismantling time more important, risk of forgetting a capacitor.||Facilitate the identification, and disassembly of components.|
|Use of non compatible materials for recycling.||Incompatible materials must be sorted.|
No recycling of incompatible or no sortable fractions.
|Check the compatibility of material used.
Reduce the number of different materials used.
|Compatibility of components between models and brands for reuse.||Need for a significant stock of components.||Standardize components most often exchanged (motors, seals, drive, belts, etc...).|
|The tank of the machine is perforated.||Repairing too complex.||Select materials that minimize the risk of perforating the tank.|
– Eco-Efficiency Analysis of Washing machines – â€“ Life Cycle Assessment and determination of optimal life span â€“ Ã–KO Institut (2004)
– Evolution of washing machines sales in France. GIFAM (update: 01-02-2017)
– Life-Cycle Optimization of Residential Clothes Washer Replacement
– A. van Schaik and M.A. Reuter (2010): Dynamic modelling of E-waste recycling system performance based on product design. Minerals Engineering, Vol. 23, pp. 192-210.