Re-purposing LED Light bulbs

Chamberlain, Michael (2020) Re-purposing LED Light bulbs. [USQ Project]

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Lightbulbs have experienced a natural evolution over recent years, with LED bulbs becoming the primary bulb in use, partly due to obsolescence of incandescent bulb technology, as well as bans such as that introduced by the EU in 2009 of incandescent bulbs due to their inefficiency and decreased life span compared to new LED bulbs. Despite LED bulbs being the primary lighting option around the world, there is currently a lack of sufficient infrastructure supporting the recycling of these bulbs in Australia. It is estimated that 48.5M tonnes of e-waste is generated each year globally, contributed to by the disposal of LED bulbs reaching the end of their life, and only 20% of such e-waste is recycled in some form. Where e-waste is not responsibly managed and disposed of, contamination of soil and waterways by heavy metals and other toxic substances is possible. Additionally, disposal of LED bulbs to landfill is irresponsible management of scarce finite resources such as rare earth elements (REE), which can be recycled and repurposed, reducing reliance on and impact of mining virgin ore.

This research therefore seeks to evaluate current LED light bulb recycling practices and schemes, including in the private sector and local government, as well as processing technologies used in the recycling of e-waste that may be adopted in the recycling of LED bulbs. Additionally, current LED bulb design and manufacture processes are investigated to identify any constraints that may inhibit the recycling process and recommend improvements in their design to facilitate a circular life cycle and economy.

Through investigation of the design and assembly of LED bulbs, it was identified that some factors may hamper the recycling process, including an all-in-one, sealed, glued style of bulb assembly, which may restrict the ability to automate disassembly. Additionally, as the designs are not standardised, a range of disassembly techniques may be required to dismantle various types of bulb housing. Improvements to LED bulb design were therefore recommended to facilitate the end of life recycling process, including a modular design such as snap on clip style housing or threaded screw on design such as those used in other products including LED torches.

Material processing technologies currently being utilised in e-waste recycling streams were investigated to identify their suitability to LED bulb recycling. E-waste recycling processes for products such as mobile phones and fluorescent lighting were also investigated to provide a better understanding of how other e-waste products are currently being recycled, and what recycling approach can be applied and adopted for the LED light bulbs recycling. Hydrometallurgical and pyrometallurgical processing methods were both assessed, with pyrometallurgical processing selected as the preferred technology due to its ability to be expanded to large scale operations, the ability to extract a wider range of metals, and the existing infrastructure currently established which can be expanded to include provision for waste LED bulbs.

Review of existing legislation and policy in Australia identified that current product stewardship schemes and various other legislation do not currently provide provision for the recycling of LED bulbs. Furthermore, LED bulbs are classed as general domestic waste and are permitted to be disposed of to landfill despite containing heavy metals and other potentially hazardous materials. While the Product Stewardship Act includes provision for e-waste, the legislation is lacking in making provision for a range of products, including LED bulbs. Three types of product stewardship schemes were developed based on the principals of the Product Stewardship Act and existing schemes for other products, with a Consumer Product Refund Scheme ultimately being proposed as the best outcome for recycling of LED bulbs due to the incentivising of recycling through cash refunds. Evidence of success in existing schemes of similar nature demonstrates the opportunity for improved recycling of other products, including e-waste such as LED bulbs.

The framework set out for development of a product stewardship scheme requires engagement of various stakeholders including government, industry, and the community, to seek feedback on scheme design prior to implementation of pilot schemes. While outside the scope of this research, this would be the next step in development and implementation of a product stewardship scheme for the recycling of LED light bulbs.

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Item Type: USQ Project
Item Status: Live Archive
Faculty/School / Institute/Centre: Historic - Faculty of Health, Engineering and Sciences - School of Mechanical and Electrical Engineering (1 Jul 2013 - 31 Dec 2021)
Supervisors: Goh, Steven
Qualification: Bachelor of Engineering (Honours) (Environmental)
Date Deposited: 25 Aug 2021 03:58
Last Modified: 26 Jun 2023 03:56

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