An Ohio company is staking its claim to be part of an anticipated plastic-scrap-to-oil boom.
This might be the year to divert those loads of mixed plastics away from the landfill and turn that low-value scrap into valuable fuel.
“We are getting rid of a problem and turning it into a profit,” says Jay Schabel chief executive officer of Akron, Ohio-based Polyflow. The company is in the final stages of commercializing an alternative energy process utilizing mixed and dirty polymer scrap as a source for fuel and petrochemicals.
Through a pyrolitic process, it takes a mixed stream of materials and distills them into usable material. “The beautiful part of the process is that we don’t have to sort,” Schabel says.
A Missing Link
Recyclers have little problem finding recycling markets for milk jugs or soda bottles. However, sorting the mixed rigid plastics, variety of film products and other #3 through #7 plastics can be an expensive and often labor-intensive proposition that does not yield a return on the investment.
With this waste-to-energy process, recyclers can send mixed batches of any and all plastics for processing. The system accepts mixed #1 through #7 plastics as well as un-numbered plastic and rubber. The material is reduced in size if it is too large for the feeder. Then, the mixed material is fed into the processor in bulk. Anyone who can operate a loader can do the job says Schabel. There is no sorting. “You can’t screw up the loading of the mix,” Schabel says since, after all, it is a mix.
PVC is a material that is accepted in moderate amounts, say three to five percent of the load. This is because it forms hydrochloric acid in processing. However, in small amounts it is acceptable as part of the process.
The mixed material currently is processed in Polyflow’s pilot system in batches. “The classic, continuous model is down the road,” Schabel says.
In demonstrations, sorted batches of all numbers of plastics, foams and other materials are weighed and blended to simulate the typical municipal waste stream. The mix used by Polyflow during a late 2011 demonstration included composite plastic grape trays, rubber with fused foam, tires, carpet, pipes and motor oil cans with the oil foam all put into the mix.
In reality, no pre-mixing would be required once the typical blend of the waste stream is established. In a commercial operation, valuable fractions like the #2 milk jugs or #1 soda bottles would likely be segregated before processing since they are easily repurposed.
As for the remaining mixed plastic stream, many recyclers are not able to profitably remove the polystyrene foam or rubber or oily plastic from 10W-40 bottles, thus making an energy-related destination an intriguing new option.
The Polyflow Process
The process begins with separation of polymer-based materials from the MSW stream from such obvious contaminants as glass, scrap metal or even (in the worst-case scenario) animal carcasses. Many municipal programs and MRFs already create such a product consisting primarily of rigid containers #3 through #7. (Shipping to Polyflow could potentially allow programs to expand this collected mix.)
After the material is shredded it is next dumped into a unit that densifies the material. The shredding and densification processes will condense the incoming product by 13 times. These stages allow a processor to store the recommended three days’ worth of material on the floor in an enclosed facility. Or, shredding and densification can happen at remote collection sites with the compacted material more easily shipped to a central processing site.
Next, there is a nitrogen purge of the system which removes all of the oxygen in the processor. Since it is vacuum-based pyrolytic process, oxygen must be removed. Then, the burner is fired to an internal temperature of 600 to 800 degrees Fahrenheit.
The plastic material is vaporized. Gas passes through pipes to a water-cooled condenser that turns it into a liquid. The liquid then is distilled. The true proprietary value of the system is not so much in the process as it is in the design of the initial handling unit. Much of the rest is basic distillation chemistry, says Schabel.
The firm’s process generates a single stream of liquid that can be split via common distillation methods. These split streams can be blended into every-day gasoline and diesel fuels and delivered to the local gas stations. This saves transporting crude oil around the world, according to Schabel.
The end product is a liquid with a sweet, chemical smell that looks a bit like a runny honey-mustard dressing, known irreverently at Polyflow as “panther piss.” It can be further processed into several different fuels, including gasoline, diesel fuel and other petroleum products.
Today, with the prices of transportation fuels, it is more likely that it will be a replacement or additive for such fuels. However, in a couple of years, that could change.
There are some restrictions. Containers full of liquids are not allowed. Each truck load brought for processing can have no more than 10 percent contaminants by weight. Proscribed contaminants include food debris, metal, glass, paper, cardboard, ceramic, wood and any other non-polymeric materials.
Materials like tires, carpet, construction and demolition debris, and electronic scrap are usable with the Polyflow process. However, they must be segregated and supplied to Polyflow under the respective specifications for each classification. Generally, if the materials stream conforms to the typical urban mix coming out of solid waste collection trucks, there will be no problem.
Schabel differentiates the Polyflow technology from some others by noting that it creates products more valuable than crude oil. Other technologies that create electricity from polymer scrap may struggle to be financially sustainable, he says.
In terms of potential feedstock, Schabel says he sees a day down the road when companies will turn away from classic wood pallets to plastic-based shipping since the material is so readily turned into fuel. The recovered product then would be shipped to industries that blend oil products.
There is some solid residue (known as char)—about 13 percent by weight and less by volume—of the typical Polyflow waste stream. If tires, juice boxes, toner cartridges or other metal-containing products are involved, the metal can be recovered from the char. The heating does not melt them into a goo. Again, while the process can handle tires, segregating tires will make the process simpler.
The char is non-hazardous and passes the EPA’s leachate test. It will burn, Schabel says, and it burns cleaner than coal. Or, if no market can be found, it can be landfilled.
Many Happy Returns
In the typical scenario, 70 percent by weight of the material put into the system converts to fuel. Remove the tires and the carpets (and it can be an easy enough sort, says Schabel) and the yield figure rises to 83 percent by weight.
“Tires are a pain,” Schabel admits. “You can pull those streams out and increase your yield. Those dollars go right to the bottom line.”
Polymer waste gives about 33 million BTUs per ton. The Polyflow process requires roughly 1.7 million BTU of energy for processing.
“We get out 27 million BTU in energy per ton,” Schabel says, noting that is 15 times what is put in. As currently designed, something around 6 million BTUs is given off, some of it as char at the end of the process.
The material produced is a mixed stream of liquids, part gasoline-like and part diesel-like. They fondly call it South Akron Crude in contrast to West Texas Crude, which is an industry standard.
“You have to make something more valuable than crude oil,” Schabel tells those hoping to profit from the process. The process will allow production of different fuels and aromatics depending on market demand.
Roughly 50 percent of the material is in the gasoline range, 30 percent in the diesel area and most of the rest in a waxy, heavy oil akin to home heating oil. A small fraction is in paraffin waxes.
Schabel notes that the polymer based product has no tars or asphalt in it. In the typical West Texas Crude, about 18 percent is tars.
Even if the United States converted every bit of recyclable polymer to fuel, it would replace only 9 percent of what we use today, Polyflow estimates. However, as the price of fuel rises, the value of the recovered material goes up.
Private waste firms, municipal operations and primary producers with sufficient volume to recover turnings and scrap all are targets for the system.
A fully operational unit will cost in the vicinity of $10 million, plus the associated costs of shredding equipment, loaders and the crude processing. It will handle about 2.5 tons per hour.
The first full-scale, operational unit is being completed by Niagara Systems in Perry, Ohio, and should be running in the late second quarter or early third quarter of 2012.
“We have about 20 companies lined up to purchase the second commercial unit,” Schabel says, noting that selling the first will be the big challenge.
Few CEOs want to be on the leading edge of new technology. However, backing from a $1 million grant from the State of Ohio’s Third Frontier incubator program, plus an additional $1.8 million of venture capital, should go a long way to assuaging any doubts.
The author is a freelance writer based in the Cleveland area. He can be contacted at email@example.com.