electronics recycling © colin fitzpatrick. electronics recycling ability to design products for...
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Electronics Recycling
© Colin Fitzpatrick
Electronics Recycling
Ability to design products for recycling is enhanced by an understanding of the recycling process
Effectiveness is affected by the ability to collect the products, extract or liberate the target materials and return them to use
Electronics Recycling
Understanding of the materials being recovered. Primary targeted materials being high value precious metals, aluminium, copper etc… Must also concern themselves with recovery of hazardous material and low value materials such as plastics or ferrous metals
The second aspect is minimising costs. Cost of liberating the materials and cost of the logistics to acquire the products
Thoroughly developed DfR plans will address both costs involved in material liberation along with logistics and collection issues.
Recycling Technologies
Manual Disassembly– Use of hand tools and methodologies similar to product
assembly– More expensive– Valuable sub-assemblies saved
Destructive Disassembly– Grinding or shearing followed by a number of material
separation techniques– Minimises labour costs– Yields more contaminated materials – Valuable sub-assemblies are destroyed
Recycling Technologies
The technique employed defines the DfR priorities. Reduction of disassembly time not necessary for
product to be shredded If disassembly times are large and recyclable
material value is low, high probability of recycling by shredding
Especially true for products with little reuse potential such as mobile phones due to rapid product obsolesce
Manual disassembly requires hidden treasure within
DfR Considerations
Material Considerations– Relative Recyclability– Toxicity
Disassembly Considerations– Barriers during assembly to the liberation of clean
recyclable materials
Material Considerations
Recyclability is the ability and desirability of reprocessing the material
Ability to reprocess the material such that its physical characteristics closely reflect the characteristics of virgin material
Desirability of using recycled material as measured in its cost versus virgin material
Closed Loop Recycling
Potential for reuse of entire parts or subassemblies.
Reintroducing the recovered raw materials into the manufacturing stream for that specific product.
Examples include large office equipment and integrated circuits
Closed Loop Recycling
Closed Loop Recycling
Developing Closed Loop Recycling involves– Analyse the potential for testing and verification of
recovered assemblies– Reverse logistical system– Disassembly must allow recovery– Gauging potential impact on the customers
perception of the product
Commonly Recycled Materials in Information Technology Products
ELEMENTS COMPOUNDS COMPONENTS
Platinum ABS plastic Integrated Circuits
Gold ABS-FR plastic Motors
Palladium Stainless Steel Power Supplies
Silver PVC Displays
Nickel Polyethylene Lead Acid Batteries
Copper Steel NiCad Batteries
Zinc Cardboard
Aluminium Glass
Mercury
Materials Recycling
Recyclability is enhanced or restrained by the inclusion of materials that are inherently recyclable and have a significant value on the recycled material market
Reverse logistics are crucial to the Recyclability Eats into the potential value of the material
– Example PET bottles are eminently recyclable but of little value and rarely get recycled when the logistics add even small costs to the process
Materials Recycling
Recyclability of a material can be significantly decreased by how it is incorporated into the product
– Steel Inserts in Aluminium Chassis require additional processing steps for separation.
– Labels added on the surface of plastics have the same effect. Label is a contaminant and can degrade the properties of the recycled material
– Otherwise recyclable parts can otherwise be incinerated or sent to landfill due to such economic considerations
Materials Recycling
Toxic materials must be recovered and processed Recycler must be able to identify, segregate, and
aggregate the materials for the recovery process Risks include release of hazardous materials during
post disassembly processing. Plastics with brominated and chlorinated flame
retardants have the potential to produce dioxins and may be sent to landfill.
Disassembly Considerations
Goal is to liberate recoverable materials at a minimum cost (measured by disassembly time)
The recycler is subject to learning curve DfR Considerations such as visibility and
ease of access to fasteners can significantly reduce the learning curve
Disassembly Considerations
Optimum Disassembly Time
Affected by– Number of fasteners– Number of materials– Time necessary to separate dissimilar materials– Number of tools required
The Optimum Disassembly time is not necessarily equivalent to the time to completely disassemble the product but too disassemble to the point of maximum return which can be determined using the net revenue curve
Net Revenue Curve
Net Revenue Curve
Y axis represents the liberated material value minus the cost of disassembly
X axis is time to disassemble Economic Goal is to operate at the peak of the curve Hazardous materials can impede this Product design establishes the parameter for this
curve by determining the purity, Recyclability, and rate of recovery of materials
Design for Recycling Analysis
Goal is to understand the products Recyclability and generate a list of potential product improvements
Three broad categories– Increasing the value of the liberated material– Decreasing the time to liberate the material– Reducing or eliminating hazardous materials
Design for Recycling Analysis
Recovered Material Value– Improve the quality of the material– Contaminates decrease the value recovered in
recycling– Joining of dissimilar materials need special
attention including different plastics and metals– Should be joined with fasteners or clips for ease
of separation.– Adhesives and welds should be avoided
Design for Recycling Analysis
Recovered Material Value– Materials with low recycled value should be
avoided as high potential they will be not recycled due to economic considerations. This is particularly true of packaging materials
Design for Recycling Analysis
Disassembly Time Reduction– Fasteners
Number Consistency (Phillips head preferred) Clips over welds
– Modularity of Design Can be beneficial or detrimental Depends on manual or destructive disassembly
Design for Recycling Analysis
Hazardous Material Elimination– No Brainer………
Quantifying Results
At conceptual stage need qualitative techniques– Grading scheme using criteria such as material variations,
relative material toxicity, weight, size etc…– Best Employed for comparisons between design proposals
Net Revenue Curve– When design has matured