MU not just spinning its wheels with TDF

he University of Missouri is giving the phrase "burning rubber" an entirely new meaning.

In October 1997, energy management experts in Campus Facilities were given the go-ahead to burn tire-derived fuel (TDF) on a full-time basis. TDF, a fuel derived from scrap tires of all kinds, including whole tires or tires processed into shreds or chips, is environmentally more healthy, less expensive, and keeps Missouri's landscapes cleaner.

This environmental gem-of-a-program uses a mixture of 20 percent shredded one-inch tire chips and 80 percent coal. Burning this mixture cuts sulfur emissions by close to 20 percent and saves the university nearly $200,000 per year. The use of TDF as an alternate fuel also helps to eliminate approximately 500,000 waste tires per year from illegal dump sites throughout Missouri.

Once tires are shredded, the resulting chips are sifted (left and right) at various points both by machinery and Missouri Vocational Enterprises inmates and taken through a maze of conveyor belts.

"It's a win, win, win situation for everyone involved," said Ken Davis, manager of power plant engineering and utility distribution. "This is one of the best projects I've ever been involved with. It saves money, reduces emissions and cleans up illegal tire dumps."

How TDF came to MU

In 1994, the Missouri Department of Natural Resources (M D N R) gave CF a $49,999 grant to experiment with burning TDF. Once the test burns showed the environmental and economic positives of TDF, it took the CF power plant until October 1997 to obtain the necessary permits to burn TDF on a permanent basis.

MU acquires tire chips through a partnership with Missouri Vocational Enterprises, a subdivision of the Department of Corrections. Missouri Vocational Enterprises sends inmates to recover tires from Missouri's illegal dumps and then shreds the tires in Jefferson City using a $1 million shredding machine dedicated in January.

"Once M D N R gave the initial approval, Missouri Vocational Enterprises got involved by having their people do the work," Davis said. "I know it's created more opportunities for those people and helped clean up illegal tire dumps throughout the state."

Other key people in the process were Energy Management's power plant superintendent, Gregg Coffin, and senior staff engineer Sharon Stock. Power plant staff assisted with the TDF testing, and loading and unloading of the tire chips.

Why isn't TDF used at power plants everywhere?

The reason TDF was such a perfect fit at MU, but may not be at other facilities around the country, is because of the type of boilers. The university's power plant has boilers in place capable of burning TDF. Facilities without such boilers face modification costs in the millions of dollars.

"We get people calling us all the time asking us about our program but only a few have acted on it," Davis said. "Air permits, and other environmental regulations in other states could be problematic and make it difficult to get started. We just had an ideal situation."

Myths about TDF

When people hear about tires burning most have images of huge tire dumps producing billowing black smoke.

This is not the case with TDF.

TDF burns well within the Environmental Protection Agency standards of safe emissions, but without the black smoke and smelly vapors typically associated with burning tires. In fact, MU's TDF produces lower levels of sulfur dioxide than burning coal.

Mother Nature's little helper

Tires are collected from illegal tire dumps throughout the state and brought to Jefferson City where prison inmates process them into TDF.

According to Davis, TDF emissions have a higher B T U (British Thermal Unit, a unit measurement of heat or energy) value than high-sulfur coal. TDF fuel value is approximately 13,000 B T Us per pound, while coal is 11,000 B T Us per pound.

In addition to reduced fuel costs, another major advantage of TDF is the steady elimination of 4.2 million waste tires in illegal tire dumps throughout the state. Although MU will burn approximately 10,000 car tires each week, more than 5 million waste tires are generated in Missouri each year. Given the abundance of tires in the state and the nation - over 240 million scrap tires in the United States alone - there will be a TDF supply for some time.

Missouri Vocational Enterprises' new shredding equipment in Jefferson City will increase TDF productivity. The equipment allows truck tires, as well as standard automobile tires, to be converted into tire chips.

Tires disposed of illegally in dumps are also breeding grounds for mosquitoes, rodents, and other disease-carrying animals. The potential also exists for dangerous fires that are difficult and expensive to extinguish. The use of TDF is one way to eradicate these problems.

The future of TDF at MU

By saving money and helping the environment, burning TDF is yet another MU project along the lines of environmental programs such as Green Lights and Energy Star Buildings. With millions of waste tires produced each year in Missouri, the environment, the university, M D N R and the Missouri Department of Corrections will benefit for years to come.