Go Green With 3D Printing

Brickwede isn’t the first to use the term “greenwashing”, the idea that a product can be marketed as sustainable without having the credentials to back it up, in reference to the AM sector. The topic has increasingly found its way into conversations amongst those in the industry who want to ensure AM’s green credentials are more than just buzzwords and backed up by real data.

By 2050, additive manufacturing (AM) could save up to 90% of the raw material needed for manufacturing, according to a European Commission study. The U.S. Department of Energy estimates that (compared to traditional manufacturing) AM might slash waste and materials costs by nearly 90% and cut manufacturing energy use in half. This is encouraging news for any company considering the economic and environmental advantages of 3D printing.

But how environmentally friendly is business 3D printing in practice today? Let’s take a look at the sustainability advantages and drawbacks of additive manufacturing.

Circular Economy Potential of 3D Printing

(Source: Sustainable Global Resources Ltd. Recycling Council of Ontario)

For all companies to become more sustainable and environmentally friendly – which everyone from governments to trade groups to consumers agree should happen – more effort is needed to solve the problems of waste, pollution, and overconsumption of energy and raw materials. Even small companies have a role to play in recycling, making purchasing decisions with sustainability in mind, shortening their supply chains, and switching to greener office practices, such as reducing energy use.

There’s a growing focus in business (just like in our personal lives) on looking beyond our current “take-make-waste” habits and moving toward practices focused on reuse, repair, refurbishment, remanufacturing, and recycling. This minimizes our raw materials use and lowers waste, pollution, and carbon emissions.

As one example, the European Union has a goal to make all plastic packaging in Europe is recyclable by 2030. What does this have to do with 3D printing? Well, consumer-grade thermoplastics used in packaging can be a low-cost and sustainable feedstock for 3D printing, providing a high-value output for waste plastics, according to a recent study. Using local plastic waste as raw material is one of the potential major benefits of additive manufacturing.

In the aspirational circular economy where everything made can be recycled, every company that 3D prints could use recycled material as the raw material then further recycle or repurpose that material after the printed part is obsolete. Although we haven’t reached this goal yet, 3D printing today enables companies to save on raw materials, produce less waste, and other major environmentally friendly advantages. We found seven ways 3D printing today can help companies go green.

7 Ways 3D Printing Helps You Go Green

1. Design More Efficiently

3D printers can make parts with shapes and features unachievable with other manufacturing methods. You can redesign your part or product to make it more efficient and use less material. Products that were once made of multiple parts can now be printed as one, reducing material, time, and labour.

Manufacturers using 3D printing can print full moving assemblies and intricate parts, such as fuel injectors, as one piece instead of several components that have to be printed separately and then assembled, so there’s less waste product and energy used.

Autodesk-GM-generative-design-seat-bracket)

2. Use Less Raw Material

The knock-on effect of this more efficient part design optimization (called topology optimization) and part consolidation are products, such as cars and aircraft, that use less raw material and are lighter, and therefore are more fuel-efficient and emit less greenhouse gases.

Whether it’s metals or plastics, 3D printing puts the material precisely where it’s needed to create a part, instead of carving out a part from a block of material or pouring molten material in a mold and creating scrap material.

3. Repairability & Spare Parts

3D printers can quickly and cheaply make repair parts for unique or out-of-production equipment, keeping old machines and vehicles off the scrap heap and eliminating the need for more raw materials and energy to manufacture new machines and industrial components.

With the push of a button, engineers can print a part that hasn’t been manufactured in decades. For example, many militaries around the world are adopting 3D printing to extend the lifespan of older vehicles and print repair parts in the field. More recently, Airbus subsidiary Satair 3D-printed a certified, flightworthy aircraft spare part that was no longer procurable from the original supplier and would have been too costly to manufacturer with traditional means.

Some metal additive manufacturing technologies (such as laser metal deposition) can repair worn out metal parts in instances where welding or other traditional repair methods aren’t suitable. Laser metal deposition has saved millions of dollars for heavy industry and aerospace by enabling companies to repair parts instead of make new ones.

4. Make Parts Locally

3D printers can fit in your office so you can make parts, prototypes, and products locally, as opposed to shipping them from a far away. The result is less environmental impact from plans, ships, and trucks.

For example, during the pandemic, when global factory supply chains were disrupted, local companies with 3D printers sprung into action to produce face masks, respirator parts, and other personal protective equipment for first-responders in their communities. Many hospitals were able to print their own equipment or contract with local companies for relatively small 3D printed qualities.

Metal 3D painted parts from a desktop-size printer (Source: Desktop Metal)

5. Eliminate Inventory

With 3D printers, you can print on demand or print small batches instead of having a warehouse of spare and overstock parts, many of which may never be needed.

One example is the dozens of eyewear brands that have partnered with 3D printing service company Materialise to bring 3D printed eyewear collections to the market. Each eyeglass frame can be customized to the wearer and manufactured on demand, eliminating stock.

“Stock wastage has historically been a huge issue for the eyewear industry,” says Alireza Parandian, Materialise’s wearables expert. “The dream scenario is to be able to offer new eyewear designs, in multiple materials, that can be produced at a speed and quantity that matches demand, while simultaneously reducing wastage and revenue-threatening stock risk.”

Aoyama Optical France turned to 3D printing from Materialise for the We DDD collection of eyewear (Source: Materalise)

6. Streamline Manufacturing

3D printers require fewer tools, parts, and processes than traditional manufacturing eliminating much of the labour, equipment, and energy. 3D printing is often faster.

Unlike other types of manufacturing, additive manufacturing is a computer-to-part method, meaning there’s no tooling or moulds and very little labour between the digital design and its production (although some methods require post-processing).

Compare, for example, 3D printing to plastic moulding to make medical models. A medical university could use its 3D printer to print virtually any models in different materials and colours. The same models made by plastic moulding would first require separate moulds to be fashioned for each item, then a machine would melt a single plastic and pour it in the mould – a process that would need to be done at a factory. With 3D printing, the university could create any type of medical model, even patient-specific models, using just one machine that fits in an office.

Two Smart3D Macro production units each featuring four dual-extruder filament 3D printers (Source: Smart3D)

7. Smaller, Quieter Factories

One 3D printer can replace several pieces of traditional manufacturing equipment because it can print a wide variety of parts in a wide variety of materials. Less equipment makes for smaller factories and fewer emissions. 3D printing facilities can be in urban centers or closer to the point of need, rather than in an industrial park or away from residences. Plus, from the perspective of noise pollution, 3D printers are measurably quieter than traditional manufacturing equipment.

3D Printing’s Sustainability Challenges

Any one of the points above could be reason enough for companies to turn to additive manufacturing to become more sustainable. However, despite the sustainability features and potential, AM is not completely green.

The biggest environmental challenge in additive manufacturing today is what to do with waste, such as failed and obsolete prints, excess or used liquid resins and plastic powders, support material, and metal printing byproducts.

Although there’s little data on the total amount of waste that AM adds to the environment, the easier and cheaper it becomes for professionals to 3D print, the more they will print, says Jeremy Faludi, a leading researcher into the sustainability of additive manufacturing. As low-cost 3D printers enable designers to produce quick, multiple iterations of prototypes, it creates a new waste issue. A survey by the recycled filament maker Filamentive found that as much as 8 million kilos of 3D printed plastic waste was generated in 2020.

Lack of Industrywide Recycling Initiatives

Although the most popular plastic filament for 3D printing, PLA (polylactic acid), is a biodegradable thermoplastic made from renewable resources like cornstarch or sugar cane, it is only biodegradable after industrial handling and can’t usually be processed at typical consumer recycling or composting centers. Although AM has great potential to create a closed-loop for material use – recycling printed parts back into raw material – in practice, it is far from the norm.

Today there are just a handful of companies that produce plastic filaments from recycled plastic waste. Machines that enable companies to turn their own plastic prints back into filament are available from only a few machines suppliers, such as Filabot’s Reclaimer.

Other plastics used in additive manufacturing are even more difficult to recycle than PLA, some are not recyclable, and others, because of environmental regulations, require special disposal methods. Research abounds into possible ways to boost the sustainability of some AM materials, but no industrywide initiatives exist.

Recyclability aside, petroleum-based plastics like ABS (acrylonitrile butadiene styrene) are made by environmentally hazardous oil extraction and refinement practices, making them an unsustainable material choice.

It’s even more difficult to recycle or resue plastics from selective laser sintering. “With Laser Sintering, the second most commonly used 3D printing technology, up to 50% of the powder becomes waste,” according to material manufacturer Materialise. “The potential to recycle used powder is limited and 3D printing with only used powder creates surface problems that make the 3D printed object unsuitable for most applications.”

Poly-Shape printed a plate of functional hydraulic blocks using Constellium’s Aheadd metal alloy (Source: P.Urvoy / Polyshape)

Metal Recycling and Energy Consumption

Metal powder left over from a print can be reclaimed and reused for more prints, but there’s a limit to the number of times it can be reused and maintain its integrity. In many high-tech industries, such as aerospace, specific and verifiable metal qualities are required, which discourages reusing material.

Eventually, businesses must dispose of their excess metal powder like they would any metal scrap, and it typically doesn’t end up in landfills. Metal powder condensate, however, which is also produced in the metal printing process, has to be disposed according to hazardous waste guidelines.

Creating metal powder for additive manufacturing from metal raw material via atomization is an energy-hungry process, which also creates some metal byproduct.

Faludi and his co-author, Corrie Van Sice, concluded, in the most recent AMGTA research, that metal 3D printing “is an environmental benefit when resource-intensive materials such as titanium are greatly reduced, or when lightweight designs enabled by AM result in significant energy savings in the use phase. However, because it is unclear where these benefits will be strong enough to overcome the increased processing energy, much more research is required to enable modeling and prediction to support decision-making.”

An SLA print emerges from the vat of resin (Source: NerdVid)

3D Printing Will Grow Greener Over Time

Additive manufacturing is still a young industry full of innovative start-ups looking for ways to differentiate this market from traditional manufacturing. Start-ups in additive manufacturing are keenly aware of their potential to offer sustainable manufacturing alternatives to companies seeking to go green. Because AM is highly dependent on technology, it may be more flexible, adaptable, and hold greater promise for growing even greener in the years to come.

There’s huge potential for additive manufacturing to be a part of the solution to a more sustainable future, but materials, technology, and industry practices still need to advance to make that happen.

* Access “State of Knowledge on the Environmental Impacts of Metal Additive Manufacturing © Nov. 2020, AMGTA” at the Additive Manufacturing Green Trade Association.

https://all3dp.com/4/7-ways-3d-printing-helps-you-become-eco-friendly/