Open Source Waste Plastic Granulator

Abstract

In order to accelerate deployment of distributed recycling by providing low-cost feed stocks of granulated post-consumer waste plastic, this study analyzes an open source waste plastic granulator system. It is designed, built, and tested for its ability to convert post-consumer waste, 3D printed products and waste into polymer feedstock for recyclebots of fused particle/granule printers. The technical specifications of the device are quantified in terms of power consumption (380 to 404 W for PET and PLA, respectively) and particle size distribution. The open source device can be fabricated for less than $2000 USD in materials. The experimentally measured power use is only a minor contribution to the overall embodied energy of distributed recycling of waste plastic. The resultant plastic particle size distributions were found to be appropriate for use in both recyclebots and direct material extrusion 3D printers. Simple retrofits are shown to reduce sound levels during operation by 4dB-5dB for the vacuum. These results indicate that the open source waste plastic granulator is an appropriate technology for community, library, maker space, fab lab, or small business–based distributed recycling.

Distributed Manufacturing of Open Source Medical Hardware for Pandemics

“…In all cases, the designs are evaluated to determine if they can be completely digitally manufactured, ideally from locally-sourced waste products. In some instances, using distributed recycling and additive manufacturing (DRAM) [108][109][110][111][112][113] is possible as the technologies (open source granulator [114], pelletizer [115], and recyclebot (an automated device to make filament for fused filament fabrication-based material extrusion 3-D printing) [116][117][118]) are already mature for pure polymers [108,[119][120][121][122][123][124] and complex plastic packaging, blends, and composites [125][126][127][128][129]. In addition, direct material extrusion of waste is now possible for additive manufacturing [112,[130][131][132][133][134][135].…”

Open Source Filament Diameter Sensor for Recycling, Winding, and Additive Manufacturing Machines

“…Using a recyclebot process, the recycling of plastic waste consists of three stages: 1) shredding used printed parts or post-consumer waste plastic into small granules, 2) melting and extruding them into filaments, and 3) 3-D printing the filament into new products (Dertinger et al, 2020). There are several commercial shredders and extruders available on the market (Obudho, 2018) such as SHR3D IT (3devo, 2020), Filabot (Filabot, 2020), Filastruder (Filastruder, 2020), ProtoCycler (ReDeTec, 2020, as well as open-source versions like the open source waste plastic granulator (Ravindran et al, 2019), Plastic Bank (Plastic Bank Extruder v1.0, 2020, Precious Plastic (Preciousplastic, 2020), the RepRapable Recyclebot (Woern et al, 2018a) and others. Regardless of the equipment used for filament extrusion, the control of a filament diameter consistency is a key stage in the recycling process (Cardona et al, 2016).…”

Planstic: Biodegradable Plastic with High-Entropy Fibers Made from Waste Plastic and Plant Leaves

“…Granulation is a physical process of recycling plastic waste. Most recyclable plastics are ground into granules by mechanical processing and then further processed into new plastic products . Pyrolysis is a kind of chemical recovery technology, which can convert plastics into fuel oil, natural gas, and other solid fuels by cracking C–C bonds in plastics under high temperatures .…”