Closed-loop recycling

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Usually, when someone decides to launch a startup company, they start small. But not Bob Daviduk and Joe Ross. When they established rPlanet Earth, they set up a company that recycles post-consumer PET containers and converts the flakes into food-grade preforms, extruded sheet, and thermoformed packaging in a single, closed-loop process. 

Bob Daviduk and Joe Ross envision a world without plastic waste. “It’s a very ambitious goal, but you have to aim high from day one,” explains Bob Daviduk. Plastic is a valuable resource, but only around nine percent gets recycled worldwide. The rest lands in incinerators, landfills, or worse – the environment.

Daviduk and Ross both hail from the United States, where daily consumption of single-use plastics is staggering: there’s coffee in to-go cups, disposable cutlery, and even peeled hard-boiled eggs in plastic containers. But when it comes to recycling these products, things look pretty grim: “In terms of sustainability, the US is an emerging market. We recycle one in five bottles give or take. In Europe, it’s closer to five out of ten. In Germany, it’s over 90 per cent because of the deposit,” says Daviduk. In the US, only one-fifth of the states have adopted a deposit and redemption system for PET and glass bottles and cans. But where there is a system in place, it works, as these statistics show: while the collection rate averages only about 30 percent nationally, the ten states with bottle deposits have raised their collection rates to an average of over 70 percent and as high as 92 percent.

So, there’s still enormous potential for deposit-refund systems to more than double or even triple the average collection rate. What is primarily in place right now, though, is curbside recycling, which is available for most plastics, paper, and aluminum. All of these materials land in a big collection bin, get pre-sorted, and then sold for further processing.

Growing demand for recycled PET (rPET) packaging

But returning bottles for recycling is just one (extremely important) part of a functioning recycling process. Of course, the goal is to ultimately make the best possible use of the post-consumer PET and convert it back into high-quality products.

And that is where rPlanet Earth comes in. The company’s two founders have recognized the market’s enormous potential. “I have been in the plastics industry for over twenty years. Unfortunately, most people don’t give any thought to what happens to plastic once it’s been used. So, our goal is to produce plastic packaging for a broad array of consumer packaged goods (CPG) companies and then be able to take that used plastic and turn it right back into the

same product,” explains Joe Ross. Bob Daviduk adds: “There is strong demand for rPET across almost every CPG company, but not enough material. The market is growing fast. A few years ago, most companies were satisfied if their preforms had 25 percent recycled content, and now many are saying they want 100 percent. Many brand owners see that as their contribution to protecting the environment and promoting sustainability,” says Bob Daviduk. And that is why the two entrepreneurs decided to start up a company that converts used PET containers back into new food-grade packaging – an ambitious project for a start-up.

Once they had secured financing, Daviduk and Ross began to look at technology and equipment in earnest. And it was purely by coincidence that rPlanet Earth found Krones: “I was looking for equipment suppliers and was just googling around when I found Krones – and the German company sounded interesting to me,” explains Daviduk. “Six years ago, Krones wasn’t really known in the PET recycling field. But my business partner Joe and his brother were both in the packaging industry and, of course, knew Krones. So I called – and was immediately put in touch with the right people; first in Neutraubling, then here in their Franklin, Wisconsin, office.” Joe Ross adds: “What started as doing some research turned into some really tight relationships with everybody from the recycling experts in Germany to the local people in the US and even the directors. We’ve gotten to know the Krones family very well and we consider them friends.”

Krones served as one of the general contractors, integrating the front end for sorting and shredding the post-consumer PET containers, its own cleaning and decontamination modules, and all pneumatic material conveyance. The line processes approximately 6,600 pounds of PET per hour. “Before we decided on Krones, we looked at some projects around the world that were already using Krones equipment. We were quite impressed by how mechanically sound the equipment was and how little manual labor was involved,” says Ross. Daviduk adds: “We believe that Krones offered the most comprehensive and the best recycling system in the world. And we fully expect Krones to live up to that.”

Krones as one of the general contractors

Of course, a plant of this size needs a lot of space. rPlanet Earth found that space in Vernon, California, about five miles southeast of Downtown Los Angeles. Vernon is an industrial city with its own power company, which provides competitively priced electricity. The facility sits on a 657,000 square-foot property (about 15 acres) that houses a logistics yard for truck traffic, a covered collection area for PET plastic bale receiving and storage, and the 302,000 square-foot plant at the heart of it all. The plant itself consists of three different sections:

–          In the front end, the feedstock is debaled and sorted using multiple technologies. When the sorting is complete and only PET plastic containers remain, they are then shredded.

–          The resulting flake enters a MetaPure W wash line, which removes any remaining contaminants and foreign matter and cleans the flakes in several stages. Another sorter at the end of the wash line ensures that only PET flakes move on to the next processing stage.

–          In the MetaPure S decontamination reactor, the flake is heated to around 390 degrees Fahrenheit (200 degrees Celsius) – depending on the target application – under a vacuum. Flake that has passed through this step is safe and approved for direct food contact packaging. The rPET flake continues right on to one of the plant’s plastics processing lines, where it is converted into preforms or extruded sheet. The latter is also used as the basis for producing thermoformed containers downstream.

This closed loop is both extremely compact and highly complex and is ultimately what sets rPlanet Earth apart. “The setup was important for us for a couple of reasons. One is because, as far as we know, it gives us the lowest carbon footprint for packaging worldwide,” explains Bob Daviduk. “Another is that it just made sense for us to have everything under a single roof because it’s a more efficient process. At rPlanet Earth, our goal is to have the lightest possible impact on the environment, on our planet Earth.”

Skipping the pellets

The PET material recycled in rPlanet Earth’s new plant goes directly into the production of preforms, sheet, and thermoformed containers. “When we developed our business model, we didn’t want to be centered on one value stream. We wanted to show the versatility of what we’re doing in recycling,” explains Joe Ross. The decision to produce precisely these three products was based on logical criteria: the primary use for recycled PET is bottle production. In the US alone, the market for PET beverage and food bottle production is some 6 billion pounds a year. For that reason, preforms make up around 35 percent of the rPlanet Earth plant’s output. Thermoformed containers make up around 50 percent. “We’re in a highly populated area that produces and consumes a lot of food packaged in thermoforms,” adds Joe Ross. Sheet extrusion makes up about 15 percent of the product mix. rPlanet Earth can produce all three packaging types with up to 100 percent recycled content, depending on customer specifications.

Food-grade products at rPlanet Earth

Preforms: 35 percent
Thermoforms: 50 percent
Extruded sheet: 15 percent

rPlanet Earth bypasses the traditional step of pelletizing, instead using the flake directly in its own plastics production. Together with Krones, the company developed a process in which the still-hot flake is converted into product in three sheet extrusion and two injection molding machines. That reduces the amount of time the PET is heated, which benefits both material quality and energy efficiency. To ensure that everything went smoothly, rPlanet Earth placed high importance on having a Krones project lead on site all the time in the early stages not only to make sure everything was installed properly but also to do any necessary fine tuning and immediate troubleshooting during the initial stages of operation.

Concrete plans for expansion

The Krones lines passed final inspection at the end of 2018 and the entire plant is expected to be online by the end of 2019. But Bob Daviduk and Joe Ross are already looking ahead to the next phase. Because of the rising demand for food-grade packaging made from recycled PET, they are already making plans to install a second line in the same building, with 50 percent more capacity, right next to the existing one in Vernon. That would make the Vernon plant the world’s largest PET recycling plant of its kind.

But as if that weren’t enough: in the years ahead, rPlanet Earth wants to open three or four more plants across the country, in regions with high population densities that collect a large amount of post-consumer PET and put them close to their end customers. “We’ll keep Krones busy,” laughs Bob Daviduk. “It will be really exciting for all of us.”

Three separate sections

rPlanet Earth uses primarily post-consumer plastic waste from curbside recycling programs that has been pre-sorted and baled prior to delivery to the facility. rPlanet Earth’s plant is split into three parts to ensure that dirty feedstock cannot come into contact with the food-grade end product.

The front end

The debaler breaks up the feedstock into a single stream of bottles and thermoforms and distributes them along a conveyor. Although the bales arrive pre-sorted, they nevertheless still contain some unwanted materials like metals or other types of plastics. rPlanet Earth’s sorting line needs to produce a pure supply of PET. To ensure that only PET makes it through the sorting and into the next stage of processing, rPlanet’s front end consists of multiple manual visual inspections as well as automated, camera-based sorting procedures. Plastics and metals that are removed from the stream are sent to other recyclers for processing.

Three grinding systems shred the positively sorted PET containers into flake, which is then stored in buffer silos. The silos make it possible to have a constant supply of PET flake and control the volume of flake being fed into and processed in the washing module. They also help maintain the strict separation between the dirty and clean areas.

The wash line

The second part of the plant is the Krones MetaPure W wash line. The flake first undergoes a dry pre-cleaning to separate out any remaining loose label material. It is then pre-washed to remove coarse dirt and contaminant particles. Finally, a caustic treatment removes labels and adhesives from the PET flake. That (lighter) material and polyolefin (PO) plastics from caps are then separated from the heavier PET material in a float-sink tank and skimmed off. The flake is rinsed several times with hot water and then dried before a final sifting to remove any remaining dust or fine particles. Flake sorters are installed after the washing module. This final inspection separates out any remaining metal, colored PET flakes, or pieces of different plastics.

To ensure the highest quality recycled material, the flake is then fed into five quality control silos. The company’s own lab team continuously draws samples from the silos and tests them for purity. Only material that has passed this inspection is sent on to the next stage of processing. If a silo is found to contain non-compliant material, the batch is sent back through a special re-sorting line.

Decontamination and further processing

The final portion of the recycling line contains the MetaPure S decontamination modules, where the cleaned flake is converted into food-grade rPET material. First, the flake is dried and pre-heated in a crystalizer. In a second unit, the flake is heated to process temperature as it passes through two heated feed screws. The flake then enters a 50-foot tall vacuum reactor, the heart of the decontamination module. Here, any contamination that has migrated into the flake at the molecular level is removed and at the same time the intrinsic viscosity (IV) of the plastic is increased. The specific IV will depend on the requirements of the end product. The IV will need to be higher in preforms that will later be used for carbonated soft drinks (CSDs) and for certain sheet/thermoforming applications than rPET used for still water preforms or sheet/thermoforms used in produce applications.

In most operations, the flake would at this point be melted down and converted into pellets (or granulate) before being processed further into an end product. rPlanet Earth skips this step. Instead, the still-hot food-grade flake is fed directly into the adjacent production lines, where it is made into preforms or extruded sheet that can then be further processed into thermoformed containers. This layout considerably reduces energy needs, since it skips two additional heating steps: for pelletizing and for pre-processing drying. It also enables rPlanet Earth to have the lowest carbon footprint among PET recyclers and converters worldwide since the flakes are converted into preforms, sheet, and thermoforms directly on site in an extremely efficient process instead of being transported by truck to different plants that perform just some of the tasks.