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IEC TR 62635: EEE Recyclability Rate Calculation and End-of-Life Information
IEC TR 62635 addresses one of the most pressing challenges in sustainable electronics: how to quantify the recyclability of electrical and electronic equipment (EEE) and facilitate effective information exchange between manufacturers and recyclers. As waste EEE (WEEE) volumes grow globally, this technical report provides a structured methodology for calculating recyclability rates and recoverability rates based on product mass, while establishing a common language for stakeholders across the product lifecycle. This article explores the technical framework, calculation methods, and practical implementation of the standard.
1. The End-of-Life Treatment Framework
IEC TR 62635 defines a four-phase EoL treatment process that forms the basis for all recyclability calculations. Understanding these stages is essential for correctly assigning recycling rates to product parts.
| Phase | Description | Key Operations | Output |
|---|---|---|---|
| 1. Pre-treatment | Hazard mitigation and selective dismantling | Removal of batteries, PCBs, capacitors, hazardous materials | Separated parts for reuse, selective treatment, or material recovery |
| 2. Material separation | Mechanical, chemical, and thermal processing | Shredding, magnetic separation, eddy current, gravimetric sorting, smelting | Recycled metals, polymers, and other materials |
| 3. Energy recovery | Combustion of residual fractions | Incineration with energy capture | Heat, steam, or electricity |
| 4. Disposal | Landfill of non-recoverable residues | Controlled landfill operations | Final waste |
The standard emphasises that actual recycling processes may vary significantly. The generic four-phase model is designed to be flexible enough to accommodate different regional practices, facility capabilities, and regulatory requirements while maintaining a consistent calculation framework.
The product parts flowing through this process are categorised into four distinct types, each with its own recycling rate characteristics: (a) reusable parts, (b) parts requiring selective treatment for de-pollution, (c) parts made of single recyclable materials, and (d) parts difficult to process (e.g., large castings, motors, compressors). The remaining bulk material stream undergoes mechanical separation after shredding.
2. Product Information Provision by Manufacturers
2.1 What Manufacturers Must Declare
Clause 5 of the standard details the information that manufacturers should provide to recyclers. This goes far beyond simple material declarations. For each part that requires removal before shredding, the manufacturer should identify:
- Part identification — unique reference, name, and function.
- Purpose for dismantling — reuse, selective treatment, single material recovery, or difficulty in processing.
- Location — physical position within the product, aided by sketches or drawings.
- Part mass — critical for the mass-based recyclability calculation.
- Material composition — declared according to IEC 62474 material declaration standard.
A reusable part can only be counted as such in the recyclability calculation if two conditions are met: (1) the part can be separated from the product while maintaining functional integrity, and (2) the manufacturer can provide evidence of a commercial reuse and refurbishment system, such as contracts with commercial partners or marketplace availability of refurbished parts.
2.2 Hazard Identification
Manufacturers must identify potential hazards to recycling personnel, including batteries, power capacitors, springs under tension, high-pressure fluids or gases, and components containing hazardous substances such as PCBs, asbestos, or radioactive materials. The standard provides an indicative list in Annex A covering items commonly regulated worldwide, from CRTs and LCD displays to electrolyte capacitors exceeding 25 mm in height or diameter.
3. Recyclability and Recoverability Rate Calculation
3.1 The Mass-Based Formula
The core of IEC TR 62635 is the quantitative calculation methodology defined in Clause 7. The recyclability rate Rcyc and recoverability rate Rcov are calculated as follows:
| Symbol | Definition |
|---|---|
| m(i) | Mass of the i-th part |
| RCR(i) | Recycling rate of the i-th part in the corresponding EoL scenario |
| RVR(i) | Recovery rate of the i-th part in the corresponding EoL scenario |
| mEEE | Total product mass |
Recyclability rate: Rcyc = [Σ(m(i) × RCR(i)) / mEEE] × 100 %
Recoverability rate: Rcov = [Σ(m(i) × RVR(i)) / mEEE] × 100 %
The key difference between the two rates is that the recoverability rate includes energy recovery fractions, while the recyclability rate is limited to material recycling and reuse. For example, a plastic part may have a recycling rate of 70 % (70 % of its mass is mechanically recycled) but a recovery rate of 90 % (the remaining 20 % goes to energy recovery).
3.2 Calculation Flow
The standard prescribes a six-step calculation flow: (1) select an appropriate EoL treatment scenario, (2) prepare product data with part masses and material descriptions, (3) identify dismantled parts and assign their RCR/RVR from the scenario, (4) classify remaining parts by material separation stream (metal vs. non-metal), (5) assign separation-process recycling rates, and (6) compute the final rates. An example in Annex E demonstrates this with a refrigerator calculation achieving a recyclability rate of 75.3 % and a recoverability rate of 81.9 %.
When selecting an EoL scenario, manufacturers should use regionally appropriate data. The standard provides two worked examples: a Korean scenario (KEA CE-3500 for large household appliances) and a European scenario (G-SCOP/CODDE study for multiple product categories). These differ significantly in recycling rates for certain materials, reflecting regional infrastructure differences.
4. Recycler Information and Feedback Loop
The standard establishes a bidirectional information exchange. While manufacturers provide product data, recyclers must document their process capabilities, including material separation effectiveness, recycling rates for specific part categories, and pollution prevention measures. This feedback enables manufacturers to improve design for recyclability in subsequent product generations—a core principle of Environmentally Conscious Design (ECD) as described in IEC 62430.
Key information from recyclers includes: contact data and process diagrams, material separation process capabilities (including minimum purity requirements, size restrictions, and achieved recycling rates for single-material parts and difficult-to-process parts), and disposal documentation with validated records from downstream processors.
Recyclers are explicitly advised to report actual performance rates, not theoretical equipment capabilities. The recycling rates should reflect the real output of the system employed, which may vary significantly by facility, region, and time. Using optimistic theoretical values would invalidate the entire recyclability calculation.
5. Engineering Design Insights
IEC TR 62635 offers practical guidance for design engineers aiming to improve product recyclability:
- Design for easy dismantling. Parts made of single recyclable materials that are easy to access and separate achieve recycling rates of 90–98 % (e.g., ABS, PP, steel, aluminium, copper). In contrast, mixed-material assemblies processed through general separation achieve only 70–80 % for the same materials.
- Avoid material contamination. Reinforced plastics (glass fibre, talcum) and blended polymers (PC/ABS, PET blends) typically have a 0 % recycling rate through mechanical separation because the reinforcing phase cannot be economically separated from the matrix.
- Mark materials clearly. Material labelling per ISO 11469 and IEC 62474 enables sorters to identify and route single-material parts to the appropriate recycling channel, significantly improving recovery outcomes.
- Plan for hazardous substance removal. Batteries, PCBs, capacitors, and flame-retardant plastics require selective treatment. Their removal should be designed as a simple, tool-free operation where possible to reduce labour costs at the recycling facility.
The single most impactful design change for improving recyclability is minimising the number of material types in a product and ensuring that incompatible materials can be easily separated. Products designed with snap-fit joints rather than adhesive bonding or overmoulding achieve substantially higher recycling rates across all EoL scenarios.
Frequently Asked Questions
Q1: How does IEC TR 62635 relate to the WEEE Directive?
While IEC TR 62635 is an international technical report (not a directive), its methodology is widely referenced in the context of the EU WEEE Directive and similar regulations worldwide. The standard provides the technical calculation framework that supports regulatory compliance, but it does not itself set binding recycling targets.
While IEC TR 62635 is an international technical report (not a directive), its methodology is widely referenced in the context of the EU WEEE Directive and similar regulations worldwide. The standard provides the technical calculation framework that supports regulatory compliance, but it does not itself set binding recycling targets.
Q2: What is the difference between recyclability rate and recycling rate?
The recyclability rate is a design-phase predictive metric calculated according to IEC TR 62635. It estimates what fraction of a product’s mass could be recycled based on its design attributes and a chosen EoL scenario. The recycling rate is an operational metric measured at a recycling facility—the actual fraction of mass that is successfully recycled during real-world processing.
The recyclability rate is a design-phase predictive metric calculated according to IEC TR 62635. It estimates what fraction of a product’s mass could be recycled based on its design attributes and a chosen EoL scenario. The recycling rate is an operational metric measured at a recycling facility—the actual fraction of mass that is successfully recycled during real-world processing.
Q3: Can the calculation be applied to products containing rare earth elements or critical raw materials?
The current mass-based approach has recognised limitations for critical raw materials. A small mass of rare earth elements may have high economic and environmental value, but their contribution to the recyclability rate percentage is negligible. The standard acknowledges this and notes that mass-based calculation is “not the only criteria to ensure material-efficient design.”
The current mass-based approach has recognised limitations for critical raw materials. A small mass of rare earth elements may have high economic and environmental value, but their contribution to the recyclability rate percentage is negligible. The standard acknowledges this and notes that mass-based calculation is “not the only criteria to ensure material-efficient design.”
Q4: How often should EoL scenario data be updated?
The recycling industry evolves continuously. The standard recommends using the most recent and appropriate scenarios when calculating recyclability or recoverability rates. The European scenario data (2005–2008) in Annex D is acknowledged as having limited temporal validity—users should always verify that their chosen scenario data reflects current industrial practices.
The recycling industry evolves continuously. The standard recommends using the most recent and appropriate scenarios when calculating recyclability or recoverability rates. The European scenario data (2005–2008) in Annex D is acknowledged as having limited temporal validity—users should always verify that their chosen scenario data reflects current industrial practices.
