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
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 ELEMENTSCOMPOUNDSCOMPONENTS PlatinumABS plasticIntegrated Circuits GoldABS-FR plasticMotors PalladiumStainless SteelPower Supplies SilverPVCDisplays NickelPolyethyleneLead Acid Batteries CopperSteelNiCad Batteries ZincCardboard AluminiumGlass 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
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