When a product or packaging is recycled, most consumers have the impression that all that material is somehow reborn into a new life as another product or packaging, which they can repurchase. Those of us in the industry however, know it’s not quite how it works. Commodity pricing, inventories, regulations and ultimately landfill economics are what really drive the recycling markets. When it is less expensive or more profitable (or required by law) to divert a material stream from the landfill, it will be done.

Land in Europe is more scarce than in the United States and consequently, landfilling is a more expensive alternative to recycling. But the United States is catching up quickly as entrepreneurial ingenuity takes over the recycling industry. One of those resourceful companies is Bala Cynwyd, Pennsylvania-based Sustainable Fuels, Inc. which takes recycled plastics otherwise destined for the landfill and transforms them into a viable coal substitute burned in the regional cement kilns.

Recycled is Not Always Recycled

“Most people don’t realize that as much as 30 percent of ‘recycled’ material still ends up in the landfill anyway,” he explains. “Especially post-consumer recyclables. The entire industry is commodity driven, and if prices are not high enough to sustain a market then inventories get landfilled. We provide a mechanism for some of that material to have an aftermarket value as a fuel, accomplishing landfill diversion after all.”

All plastics have a resin identification code from 1-7 that denotes their specific polymer content. Most recycling facilities target plastic codes 1-3 that are always in demand. Other collected plastics must be more actively marketed to sell at a profit or they risk being ultimately landfilled. That is where Sustainable Fuels adds value.

“We really do take the most undesirable plastic materials off the hands of the recycling companies. Plastic coded 4-7 is often just waste for them, although 5s are starting to be recyclable again,” he continues. “Our other major material source is pre-consumer industrial which we collect directly from the manufacturers in bulk.”

Saving Fuel While Producing Fuel

Roughly 18 months ago, Sustainable Fuels purchased a new Doppstadt DW 3060K slow-speed shredder to handle the primary reduction of their incoming material. The decision was made to replace a medium speed wood grinder that had been previously tasked with that responsibility. Not surprisingly, the grinder was not nearly the right machine for the job.

“Even if we do presort perfectly, there is always some contaminants that make it into the reduction process,” Gordon explains. “And the shear volume of material we were running would constantly choke up that grinder and stall it out if not break it down completely. It was really difficult to maintain steady production.”

“I had been running Doppstadt shredders at my previous company, so I was well familiar with them,” he continues. “They are just phenomenal, you don’t really have to do anything to them, other than some simple periodic maintenance. We worked with Andy Lawrence at Ecoverse and he helped match us with the right model for our operation, and the 3060K has been exactly what we needed.”

Immediately, the results showed. Throughput increased, downtime was virtually eliminated and fuel usage was cut nearly 75 percent.

“We burn somewhere between 6-8 gallons per hour now, where before we could burn through more than 30 per hour with the high speed. I simply can’t exaggerate the difference.”

Post reduction, the material flow passes through a wind sifter heavy-fraction separator to removes metal.

“We have magnets on the shredder discharge conveyor to pull out ferrous, but for non-ferrous metals, the wind sifter is much more economical and offers higher throughput than an eddy current system,” Gordon adds.

Then the high-speed grinder performs the final reduction to a light, fluffy 1” minus product, perfectly designed to be pneumatically blown into the cement kiln and generate high heat output.

Precise, Proprietary Blending

Overall, producing their fuel is not tremendously complicated. The real proprietary value comes from achieving the right blends in the output to ensure compatibility with the cement kilns.

“A tremendous amount of effort goes into the analysis of all the material we take in and convert to fuel,” shares Gordon. “We need to meet specific BTU heat values and understand the emissions potential of what we’re producing. Our product has value to the cement plants because as a coal substitute, we can provide a heat value equal to, and often greater than, coal but with fewer emissions. So burning our fuel requires less scrubbing on their end and there is real economic value to that.”

Gordon shares that a study done at one of their kiln customers determined that the heat value of every ton of their fuel product was equivalent to 1.2 tons of coal.. Dramatic performance for a product made entirely of disposed plastics mixed with a little wood, cardboard and paper.

Presort is still important to the process, even with the slow-speed shredder in place. Obviously, any contaminants they find are removed. But the sorting and segregation of materials allows them to introduce each material fraction with a precision that fulfills their specific blending recipe.

“And most recently we added a new inline fuel analyzer over the shredder discharge conveyor than can tell us in real time exactly what we’re making and notify us if there are any spikes or deviations. It’s a very precise process.”

Huge Growth Potential

Sustainable Fuels has a geographic factor to their advantage, being located by five major cement plants within a one-hour drive. Nowhere in the country is there a greater density. They are also perfectly positioned outside of Philadelphia, where a steady stream of both pre- and post-consumer waste can be easily obtained to produce their fuel.

Gordon and his team studied the rest of the country and have identified several other markets with a similar profile.

“We see great opportunity is a handful of major markets in other states, and we’re planning our growth now. I see a ton of untapped potential for what we’re doing and I think with some additional research, we can adapt this process for other generation plants as well,” says Gordon. “It’s a very exciting business to be in right now.”