A New Dimension of Recycling

A robot made on a 3D printer at NextFab studio | Photo by Addison Geary

A robot made on a 3D printer at NextFab studio | Photo by Addison Geary

3D printing is a breakthrough but also creates unwanted material

by William Beisley

The 3D printer was first patented in 1986 by Chuck Hull, co-founder of 3D Systems. The initial purpose of the machine was to expedite labor-intensive and costly milling procedures for companies prototyping new products. Hull’s stereolithography apparatus (SLA) employed a computer-controlled ultraviolet laser that solidified liquid photopolymer resin in accordance with a virtual design. Resin would be reapplied and shaped before being cleaned and cured in an ultraviolet oven.

In recent years, the 3D printer has become increasingly more powerful, popular and versatile. Doctors and engineers are using the technology to create everything from prosthetic jaws to tracheal molds; hobbyists are individualizing production by designing and printing their own kitchen utensils and children's toys; developers are even 3D printing eco-friendly vehicles such as the Urbee, a crowd-funded hybrid car that reportedly exceeds 300 miles per gallon.

These diverse applications are why many analysts refer to 3D printing as a harbinger of a new industrial revolution. As the method becomes more ubiquitous, makers should concern themselves with materials, toxicity and waste: three issues from that first industrial revolution whose impacts we’re still reeling from in the form of lasting environmental pollution, overfilled landfills and compromised human health. 

“I think there are ways to make [3D printing] sustainable, but I see much more focus on the potential for innovation than on the potential for risk and waste,” notes Stephanie Alarcon, measurement lab technologist for the Open Technology Institute in Washington, D.C. “That’s a shame because we have such clear histories about how previous innovations have created novel waste problems.”

Users of 3D printers should be aware of the high energy use that the machines expend, especially when printing in bulk. Energy consumption during mass-production is the one area where traditional mold-injection machining still has the upper hand. 3D printers are at their most helpful when going through a rapid prototyping process, necessarily an iterative beast that can eat up energy and resources. 

End-of-life treatments are particularly worrisome, despite the marketed reusability of the materials used for printing. Polylactic acid (PLA) is one of the most common thermoplastics used in 3D printing. It’s biodegradable—and happens to be what is used to make compostable cups. However, it is up to the operator to properly dispose of excess material. If the user doesn’t have a complete understanding of how to compost the leftover PLA, it could end up in a landfill where it would sit for roughly the same amount of time as an ordinary plastic cup—anywhere from one-hundred days to a century. 

“We are still in a sweet spot where a smart focus on the waste issues [with 3D printing] could really make a difference, and I think it could be done without a lot of effort or cost,” ensures Alarcon.

Many companies are starting to provide recycling services, and some start-ups are even manufacturing re-extrusion machines that repurpose excess material from homes, but the potential for waste is still difficult to determine. 

Despite the uncertainty concerning the sustainability of 3D printing’s future, Evan Malone, president of NextFab studios is hopeful.

“The 3D printer enables you to very quickly develop ideas, but as you’re developing ideas, you’re producing waste,” he remarks. “It accumulates on people’s desktops and in their hobby-spaces, so it becomes a very visible problem, and recycling becomes a very natural answer. The tool itself seems to suggest this solution.”