SALT LAKE CITY (Jan. 31, 2000) — Emery Recycling Corp. wants to eliminate shredding, pulverizing or treating scrap tires as anything except whole pieces.
The Salt Lake City-based company has developed a whole-tire gasification process that converts more than 92 percent of the energy in tires into a synthetic gaseous fuel, President Benjamin Phillips said.
ERC operated one pilot plant in central Utah that was close to the anticipated size of a commercial model, conducting tests on the gas and the emission product and learning how to run the facility. The firm is not operating the pilot plant now but is working with industrial groups in Utah and other states to try and identify future commercial sites, Mr. Phillips said.
"We plan another round of demonstrations at this site prior to building a commercial model," he said. That testing will let ERC determine any needed scale-up requirements for a commercial plant.
The company had built three smaller prototype facilities; one dealt with gasified coal, one with biomass and municipal solid waste, and one with tires. The company turned exclusively to scrap tires because they presented "the best near-term possibilities," Mr. Phillips said.
"We process the whole scrap tire on a continuous feed basis and convert it to a syn gas. A conveyor takes them into a gasifier. It is not pyrolysis," he said, referring to a common scrap tire disposal method.
Pyrolysis, a form of incineration that chemically decomposes organic materials by heat in the absence of oxygen, cracks shredded tires into their primary elements — carbon black, oils, gases and steel. It is a greasy and messy process.
In ERC´s system, the gasifier converts the tire into a gaseous fuel.
"The only other byproduct is iron-rich slag and ash from the steel belts," Mr. Phillips said. "That will be taken to steel mills, hopefully for resale — if not (for sale), then to avoid tipping fees. The mills have determined it´s a useful product for them."
Except for the fuel needed to start the process the first hour, the autothermal gasifier needs no fuel support.
"Unlike pyrolysis, which needs to heat the vessel, we don´t need that. That´s why we have such high efficiency," he said.
ERC has processed up to 16 tons per day at the pilot site, and drawings for the commercial-scale operation call for a feeder that can deliver 50 tons per day to the gasifier.
A few other companies in the United States use a gasification process, but none feed whole tires on a continuous basis. Most shred the tires and batch feed them, Mr. Phillips said.
"We save money by not shredding, and we don´t have to start and stop," he said.
ERC will get its scrap tire supply from within Utah.
The Utah Division of Solid and Hazardous Waste Management issued permits to the company in March 1997 for its gasification plant, which is classified under the broad category of incinerator, said Ralph Bohn, the division´s solid waste section manager.
The state has paid ERC through a fund that offers recyclers $75 per ton for every ton of tires recycled, Mr. Bohn said. Money for that fund comes from an 85-cent fee collected for every new tire sold in Utah.
ERC, which is a private company owned by investors in Utah, started working on the gasification process in 1995, but the company has existed since 1993, when it primarily was a recycling operation, Mr. Phillips said.
ERC has applied for grant money from the U.S. Department of Energy, through its Office of Industrial Technologies, to continue its efforts to go commercial.
"We haven´t received any money from the Department of Energy yet, but we hope to in the future when we mix our feedstock, especially when we blend it with coal," Mr. Phillips said.