JANUARY 2008

Microwave recycling used for auto shredder residue

Starting this May, an automobile shredding operation in Long Island, New York will be utilizing a microwave 10-ton machine developed by New Jersey-based Global Resource Corp. (GRC) to convert automobile shredder residue (ASR) into hydrocarbons – a mixture of gases and oil.

The process does not produce carbon monoxide (CO) or carbon dioxide (CO2) due to the fact that it works in a vacuum.

Frank Pringle

Although primarily designed for converting coal, shale and other natural resources into hydrocarbons, the machine, currently designated as the 10-ton recycler, could play a vital role in the recycling of rubber and plastic products to recover the petroleum that went into making them.

“We found a bunch of microwave frequencies that are out of the norm – way up the scale of industrial frequencies,” says GRC CEO and president, Frank Pringle. “We found 18,000 frequencies that go after hydrocarbons.”

It took the company 10 years and $3 million in research and development to create the technology. Its first commercial machine, the size of a small bus, cost $5.1 million to manufacture.

Following tests with materials sent to GRC by shredders, the right formulation was found.

For every 100 pounds of ASR that is processed­, 70 pounds are converted into hydrocarbons – a thick viscous combination of oils and very hot consumable gas between the 1,100 and 2,000 BTU range per cubic foot.

“There is water in it, but most of the weight is in the form of gases and oil,” says Pringle.

Distilled oil made by GRC.

The recovery of gas ranges from 50 to 60 percent. The oil and gas can then be used to power the GRC machine and supply power for the facility.

For the remaining 30 percent, on average 25 percent consists of an inert ash and 5 percent metals. The ash can be shaped into blocks and because it still contains some BTUs, it can be incinerated to generate power.

The Long Island shredder currently uses natural gas to power its facility and equipment, including the giant metal eater, which requires turbines.

“I told the owner that we are going to liberate more gases than will be required to run your machine and that you ought to get a small turbine to make electricity,” says Pringle. “He is weighing that option now. The East Coast people need this.”

Pringle estimates that the Long Island firm can recover its investment in 11 months.

GRC also has a small continuous motion lab unit that can handle as much as one ton per hour to operate at the head office. This machine would allow the company to do additional testing and analysis.

The gas that is created requires an input of oxygen to reduce the strength of the burn.

“The oils, because they are very viscous,” says Pringle, “would need to be cut with kerosene or something similar to be sold as a heavy heating oil.”

The technology can also be used to recycle discarded tires.

“I can drive my diesel truck on the oil that comes out of that,” says Pringle. “It’s a nice rich diesel fuel. A 14-inch tire weighs about 20 pounds and takes about 50 cents worth of electricity to gasify it. It’s a tremendous yield. You get 1.2 gallons of diesel fuel, 50 cubic feet of gases, 7.5 pounds of carbon black that can be used by the chemical industry, and about two pounds of steel that is stripped of any rubber on it – it has a higher value than just regular carbon steel.

“It’s worth about five dollars in those four components,” he adds. “This is a closed system. We don’t use any oxygen. It’s in a vacuum and nothing goes into the environment.”

While Pringle says his tire recycling technology is proven, he has been unsuccessful in securing permits from New Jersey to establish a plant.

“There have been so many scams out there, that when we talk to somebody,” he says, “its how do we know this is going to work, even though we have verifications from institutions and the Department of Energy. We run into this all the time.”

Pringle says that automobile recyclers would be in a good position to recycle tires because “they have all the permits and it is a closed system. Nothing goes into the environment, other than the emissions from the turbines that generate electricity and they have scrubbers on them.”

Pringle says it would be easy to establish recycling centers for tires across the United States to convert them into fuels.

Other rubber and plastic products can also be recycled using the GRC machine and Pringle says that his company is anticipating a project from one of the largest automobile recycling firms in the world.

“We can do any type of plastic,” he says. “Every day in the U.S., we bury the equivalent of five million barrels of plastic byproducts. All that can be brought back into combustible gases and oil.”

Nor do contaminated plastics stymie GRC’s machine, says Pringle, who notes that the machine could handle all types of plastic simultaneously.

“What is left over is just a clean ash that we can turn into blocks,” he says. “The PCBs are gasified and broken down into either oil or gas and are not harmful.”

In terms of energy production from raw materials, with 100 pounds of bituminous coal, the machine gasifies 30 pounds, creates 5 pounds of coal tar and another 25 pounds of methane and hydrogen.

‘To make hydrogen is very expensive – it costs more than you sell it for,” says Pringle. “What we’re doing to get 150 pounds of hydrogen or methane takes 3 minutes. The estimated energy cost is about $10 a ton. Everybody wants fuel cells and hydrogen is the key ingredient. That is 50 percent of the gases that we get out of coal.

“West Virginia has done two experiments and we are waiting for their written confirmation,” he adds. “We also produce a high grade coke material. We are doing a joint project with Penn State for oil shale and will probably do a joint project with West Virginia on bituminous coal.”