Project Overview
Approved for funding through ERA’s Circular Economy Challenge in 2023, RBW sought to develop a process to take contaminated plastic waste and produce a valuable, saleable product. By project completion in 2024, RBW successfully established a recycling process that takes waste material that was being collected, decontaminates it, and turns it into valuable products to be resold to the same customers who produced the waste.
In-house Recycling Process for Waste Plastic
RBW Waste Management Ltd. is an Alberta-based company providing hazardous waste management services throughout Canada. RBW’s largest received waste stream is contaminated high-density polyethylene (HDPE), averaging 164 tonnes annually. RBW developed an in-house recycling process for this material, which takes contaminated HDPE waste produced by Alberta’s resource extraction and industrial sectors and uses plastic extrusion technology to turn it into recycled plastic products to be sold back to these same industries. This circularity has a greenhouse gas (GHG) benefit by reducing the need for virgin plastic required to make these products, and by eliminating the transport required to ship this waste stream off-site to other recycling operations, often out of province. Additionally, keeping the plastic and recycling it in-house has a cost benefit from eliminating the transport and recycling fees.
Establishing a Circular Economy Using HDPE Waste
Throughout the project, the team’s learnings led to the process and technology selected for development, for example, determining that extrusion moulding was the most economical solution for converting waste HDPE into saleable products. RBW researched, purchased and installed conveyors, a Grinder, an Extruder, a Cooling Tank, a Mixer, a Chiller and several product-line-specific moulds. Combined with an existing Shredder and washing machines, this recycling line produces several types of moulded, recycled plastic products from waste feedstock.
RBW initially anticipated making chock blocks, but quickly determined it could not easily be made with the HDPE feedstock available. RBW designed and developed a number of different products, determining curb stops as one of the main products to make from the recycled plastic feedstock, to prevent damage to waste producers’ assets. Discovering that leveraging the different colours of plastic waste it is possible to make different colours of products without the use of dyes. This enabled the production of blue curb stops for use in designated disabled parking stalls.
RBW achieved the goal of processing all the waste HDPE received at the facility and turning it into rHDPE; having zero per cent of plastic shipped off-site for recycling purposes, although some material is sent for re-use. Additionally, RBW surpassed their initial production goal, almost doubling expectations from eight tonnes to sixteen tonnes per month. By making adjustments and adaptations to the process and feedstock composition, RBW is producing ~4,000 kilograms of recycled plastic curb stops per week.
What’s next?
The HDPE Recycling project has been an extremely positive achievement for RBW through increasing the sustainable practices and providing circularity that RBW customers want to see in the resource extraction and industrial sectors within Alberta and beyond.
Going forward, RBW plans to push the limits of how much blow-moulded HDPE material can be incorporated into the Extruder feedstock to maximize the amount of plastic recycled and ensure product quality. Additionally, developing versatile blends of HDPE that are suitable when different types and quantities of waste plastic are received, and determining additional products that can be produced. RBW aims to seek out more HDPE waste streams and sources within Alberta and connect with Alberta’s Extended Producer Responsibility (EPR) program to access different types of plastics.