Disposable products used to be the norm. Disposable batteries, disposable electronics, disposable single-use plastics, etc. That trend has slowly started to end, and most products are finding new ways to be reused, recycled, or transformed into another useable material. Plastics have long had multiple variations of recycling, but some still are not able to be recycled. For those that can’t be recycled, they have other options than just being disposed of in a landfill. They can be converted to energy. Want to know how? Read on to learn more about how non-recyclable plastics are being converted to energy…
What Exactly Are Non-Recyclable Plastics?
You probably recycle some or most of your plastic purchases, but what makes a plastic non-recyclable? Those that can’t be recycled easily have specific chemistry that prevents further use, have a production technique that hinders a second chance, don’t have the technology available to make use of them further, or just simply will cost too much to recycle. Thermoplastics can be melted and recycled over and over, so they won’t fall into that category. Thermosets on the other hand don’t soften or melt when reheated and can’t be easily recycled. Items made from vinyl, silicone, polyurethane, and epoxy fall under the thermoset category which are labeled as non-recyclable plastics.
How Are Non-Recyclable Plastics Turned into Energy?
If plastics can’t be recycled, does that mean that they are just garbage after their use? Absolutely not! Non-recyclable plastics do have value beyond their initial use. They can be turned into multiple types of fuel and energy through a process called “Pyrolysis”. Non-recyclable plastics are largely made of hydrogen and carbon, which makes them able to behave similarly to other hydrocarbon-based materials such as heating oil and gasoline. That makes them a good source for fuel and energy.
Pyrolysis has Greek roots, and the term can loosely be translated as “fire separating”. The process of Pyrolysis subjects any material to highly elevated temperatures in a relatively inert (mostly or completely void of oxygen and water) environment to promote thermal decomposition. It forces materials to chemically change from an initial composition into a different composition through a chemical decomposition reaction. Pyrolysis can generate solids, liquids, or gases that can be later used as energy and fuel. A separate Pyrolysis technique can be used to superheat plastics until they vaporize. This will produce hydrogen that can be used as a synthetic natural gas (also called Syngas). This synthetic natural gas can be used as a fuel to generate electricity in power plants and as a direct fuel for hydrogen-fueled vehicles.
Are There Drawbacks to Plastic Pyrolysis?
As many upsides as there are to creating new uses for materials, there are always drawbacks that need to be considered. Plastic Pyrolysis isn’t an easy process to complete. Plastic waste must be obtained, then pre-treated to remove any materials that shouldn’t be allowed in the Pyrolysis conversion process. That can include other waste materials or simple impurities. The pre-treated raw materials are then ground into a required size to ensure the proper reaction can occur in the Pyrolysis chamber. The process may also require a catalyst to complete the thermochemical conversion, and the process requires significant heat (between 200 – 900°C is common) for melting and vaporization to occur. The vapors are then moved through condensers to create a liquid that may be need further refining before it can be used as a fuel to create energy.
Knowing that the process requires extra labor, energy, and equipment, it may not be considered as a perfect solution for every situation. Industries are continually working on new innovations involving cold plasma pyrolysis and plasma gasification to produce a similar result more efficiently. It can also reduce or eliminate any soot or other less-desirable byproducts that conventional Pyrolysis processes generate. Previously non-recyclable plastics are finding new techniques and applications to create new opportunities for plastic materials to be reused.
How Do I Choose a Recyclable Material for My Next Plastic Project?
There are thousands of resins available for plastic products and choosing one that meets your criteria with recycling options can be a difficult decision. Each option can offer advantages but can also have drawbacks to keep in mind. SEA-LECT Plastics has the expertise to help with your decision. When you’re ready to work with our elite team that produces world-class prototypes and products, call (425) 339-0288 or email us at info@sealectplastics.mystagingwebsite.com. We look forward to offering support and advice on your next project. In the end, the material and process chosen will benefit your product design. Many resins are completely recyclable, and for those that aren’t, there are still further options to investigate to ensure they can be of further use.
Matthias Poischbeg was born and raised in Hamburg, Germany. Matt moved to Everett, Wash., after finishing his bachelor’s degree in business in 1995 to work for Sea-Dog Corporation, a manufacturer, and distributor of marine and rigging hardware established in 1923.
In 1999, Matt took over the reins at Sea-Lect Plastics Corporation, a sister company of Sea-Dog and a manufacturer of plastic injection molded products with an in-house tool & die shop. Matthias Poischbeg is also a contributor to Grit Daily.