The learning curve

Features - operations spotlight // RDF Systems

A Dallas-based recycling company is in the learning process of creating a refuse-derived fuel product it is supplying to a local cement kiln.

December 5, 2016

Richard Szarkowski, a native of Poland, started Dallas Recycling, Dallas, in 1994 with fellow Poland native Roman Krawieczynski after receiving political asylum in the U.S. under the Ronald Regan presidency.

The facility housed an old corrugated cardboard (OCC) company operated by Corrugated Services, headquartered in Forney, Texas, which still buys OCC from Szarkowski and Krawieczynski today.

“We started really, really rough,” Szarkowski says. “There was just the two of us in the beginning, and we started sorting trash in a really small place.” The facility started out as a 900-square-foot building with one old baler, one Bobcat with a forklift attachment and rented equipment.

Szarkowski says he and Krawieczynski worked 16 to 18 hours a day seven days per week in the beginning due to the small space, limited resources and language barriers.

“But our hard work final started paying off,” he says. “We got more accounts, and we hired a sales person. In the beginning, we started with residential reloaders, so we went from warehouse to warehouse, bringing back paper products and old cardboard that we baled and recycled.”

In 1998, Szarkowski exchanged his reloaders for the company’s first roll-off trailer and fuel cans. Now, the company offers 14 roll-off trucks, 6 tractor trailers, more than 100 trailers and employs about 80 people.


One issue Szarkowski noticed in his business was the unrecyclable waste that he would send to the Dallas landfill. After researching through various waste industry publications and literature, Szarkowski stumbled upon an ad for Lindner, with North American headquarters in Raleigh, North Carolina, in an issue of Renewable Energy from Waste. The ad called for businesses interested in starting a refuse-derived fuel (RDF) line.

Szarkowski spoke with Lindner President Andreas Schwarz, and after receiving a quote on equipment and flying out to Europe to meet with Schwarz, decided to make RDF from his commercial waste using a Lindner system.

The multimilion dollar system, housed in a 19,000-square-foot building, uses an in-floor loading conveyor, a Jupiter 2200 primary shredder, a ferrous magnet, a windsifter, a Komet 2800 HP secondary shredder, a conveyor system, a near-infrared (NIR) scanner and a control system to automatically run the line—a complete, multimillion dollar line from Lindner, Schwarz says.

The Jupiter 2200 primary shredder shreds the commercial waste to 12-inch minus. The material then moves through the ferrous magnet to remove ferrous metals such as iron and steel and an air knife in the windsifter to remove what Schwarz calls “heavies,” or objects such as stones, batteries and nonferrous metals.

After the feedstock is shredded and sorted, it runs through a secondary shredder to create a 2-inch minus fuel cube. The NIR scans the fuel and gives a report back to a computer, which keeps a record of the material’s British thermal unit (Btu) value, moisture content and chlorine levels.

According to Schwarz, the line is capable of running at a rate of 20 tons per hour. The fuel is packaged in a 1¼-inch square between 2 to 4 inches long.

Dallas Recycling is working with a mixture of paper, plastics and rubber. According to Szarkowski, the rubber is used to keep the fuel’s Btu-value high.

The feedstock comes from different sources and varies from tire curing bladders—nonreinforced rubber membranes that form the inner ring of a tire during the manufacturing process—to plastic palettes to large paper sacks. The feedstock will not work with a moisture content of more than 20 percent.

“We’re even working with a distributor that gives us candies,” Szarkowski says. “Sugar is combustible, brings around 10,000 Btus and can be blended with the fuel.”

The company also uses rejected diapers from the factory line, which works in the feedstock because it is made of plastics mixed with paper.

“Whatever we can get our hands on that’s dry,” Szarkowski notes.

According to Schwarz, a consistent input of feedstock and a consistent feedstock also help keep BTU value up and regulated.

Contaminants, especially chlorine that is found in polyvinyl chloride (PVC) plastics, can be dangerous to the equipment, such as filters and smoke stacks, and for the fuel as well.


While researching RDF systems, Szarkowski traveled to landfills in Italy, Germany and Austria to speak with their operators and get tips from them. There, he learned of the dangers of dust explosions.

“In England, there was a dust explosion at a facility that caused $37 million in damage,” he says. “Equipment burnt overnight and was located outside city limits, so a fire department wasn’t called in time.”

According to Schwarz, another component of running a proper RDF line is maintenance—keeping knives adjusted and changed at the proper frequency, and so on.

But the biggest learning curve for Dallas Recycling was its experience with one of its customers.

“Richard saw an opportunity and he went for it,” Schwarz says. “But he found a client that wanted a spec he couldn’t make.”

Around three years ago while searching for customers for his RDF, Szarkowski found a local cement kiln that was interested in his product and placed an order.

While the order was being processed, Szarkowski says, he noticed that the company didn’t specify the density it needed.

“In Europe, they typically make cubes that are 8 to 9 pounds per cubic feet,” he says. “But [companies in Europe] have a different heating system than this kiln.”

“They understand that we’re in the learning process, and they are, too.” -Richard Szarkowski, Dallas Recycling

The kiln needed a more dense material—around 25 pounds per cubic feet—because it needed a feedstock that was similar in weight to the coal it was using, Schwarz says.

Density issues, along with the need to install a separate cubing system to the Lindner line to meet the kiln’s specs, caused a delay in supplying the RDF to the kiln.

“But they understand that we’re in the learning process, and they are, too,” Szarkowski says.

The kiln currently has a three-year contract with Dallas Recycling, and Szarkowski says they plan to extend it. The kiln saves 90 tons of coal per day using the fuel cubes.


Szarkowski says he doesn’t give much thought to Dallas Recycling’s future—his age of 65, along with the issues he had in the beginning of his RDF production makes the future a bit foggy in his opinion.

But the learning process will not stop Szarkowksi from creating an environmentally safe alternative for his customers—at least for now.

“Slowly but surely, we are making our customers landfill free,” he says. “Corporations are excited that their trash never sees the landfill.”

The feedstock Szarkowski uses is continuing to grow in volume. Most waste, he says, is paper and plastic with glass falling to the wayside. Creating an RDF can divert these materials from landfill, but finding end users is challenging.

“I wish that we could find more companies who will use RDF, because this material is safer,” Szarkowski says. “I wish more power plants would change their fuel from coal to an alternative fuel so we can get more customers.”

With making the RDF, Schwarz says that sometimes the process is easier said than done. For customers like Szarkowski who are beginners, fully understanding the process from beginning to end is a key element in creating a successful RDF business.

“Fuel making looks easy from the outside, but the devil is in the details,” Schwarz says. “Depending on the source of the material, for example Richard is using commercial and industrial waste that is fairly dry and free of organics, then you won’t have issues later on in the process.”

The author is assistant editor of Renewable Energy from Waste and can be reached at