Plastics are ubiquitous and it would be hard to go a single day without using plastic in some form. It has become part of our everyday lives, enjoying a wide range of uses including water bottles, food containers, children’s toys and much, much more. Plastics have many advantageous properties and are easily manufactured: despite these benefits, they have become an enormous problem – plastics are everywhere, and knowing how to manage, dispose of and recycle them is increasingly challenging.
Impact of Plastics on the Environment
Plastics are having a hugely negative effect on the environment; it is estimated that more than 300 million tonnes of plastic are produced globally every year, with only 10% of that being recycled. The rest makes its way into landfill, or is found on the streets or in the ocean. In fact, it is forecast that there will be more plastic in the ocean than fish by 2050 – an alarming thought to say the least.
Converting Plastic into Filaments for 3D Printers
So, what can be done to tackle the problem of plastic waste? One environmental engineer in India has partnered with local waste collectors to turn plastic into filaments for 3D printers. In 2012, Sidhant Pai founded Protoprint, just one of a number of start-up organisations trying to find a solution to the issues of plastic waste pollution and the poor conditions in which waster pickers work. It has joined forces with SWaCH (Solid Waste Collection and Handling), a cooperative owned by waste pickers to set up a low-cost filament production facility at a rubbish dump in Pune. The facility converts plastic waste – specifically high-density polyethylene (HDPE) - into 3D printing ink which can be sold within India and worldwide.
The market for filament – the majority of which is made from virgin plastic - is growing rapidly. Prototype’s ethically produced filament is cheaper than commercial filament; the plastic waste is a free resource and production costs are lower in developing countries. However, the quality of the filament produced presents a challenge – Protoprint’s pilot product suffered warping, leading them to join together with National Chemical Labs to investigate the use of an additive to prevent deformation.
Recycling Plastic Waste
Plastics deposited in recycling bins are all too often destined for oversea plants for final reprocessing, an unsustainable process which needs to be more localised. Engineers from Australia’s Deakin University have attempted to address this problem with their EcoPrinting project. They use a polymer melt extrusion process to turn recyclable plastics into 3D printer filaments, which can then be used to manufacture items like water pipe connectors. They are currently testing the mechanical degradation of various polymers when using 100% recycled plastics and composites using virgin and plastic blends. Furthermore, they have developed a way to operate the equipment with a portable and renewable energy generation meaning it can be used in remote, off the grid areas.
Rotterdam-based Better Future Factory have been working on a similar idea; as part of their Perpetual Plastic Project, they take recyclable plastic bottles, cups and comparable materials and turn them into filaments for 3D printing. The plastic is washed, dried and shredded before being fed into an extruder where it is heated and melted into filaments. The team have made the relatively simple process mobile and travel around the Netherlands demonstrating the process, encouraging people to recycle their plastic waste into a wearable ring.
Researchers from Waikato University in New Zealand have also been working on a project to transform waste into 3D printing filament which could then be used to create a variety of high-demand products like cars parts and furniture. Fused deposition modelling (FDM) has been integrated into the method as a core component making it applicable to a number of industries and could massively decrease the levels of plastic waste.
3D printing is still considered a relatively niche industry but it is possible that one day, every household could own one. Plastics once destined for recycling – or worse landfill or the ocean – could be repurposed into filament within the home, and then printed into something useful.
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