WASHINGTON-The nation's fourth-largest cement maker is ceasing the use of hazardous waste-derived fuel at one of its plants, and may convert to scrap tires as an alternative by 1997. A spokesman for the scrap tire recycling industry said more and more cement companies are switching to scrap tires as fuel, for financial and other reasons.
Ash Grove Cement Co. announced Jan. 29 it will stop burning hazardous waste at its Louisville, Neb., facility, after using it as fuel for the past nine years.
A company spokesman said the Louisville plant would accept its last shipment of hazardous waste fuel April 1, then phase out its use over the following two months while investigating scrap tires and other non-hazardous alternatives.
``It comes down to the economics of the (scrap tire) program,'' the spokesman said. ``If it looks economically viable, we will proceed.''
Twelve employees at Louisville will lose their jobs because of the phaseout of hazardous waste, according to Plant Manager Ed Parker.
Citizens of Louisville have protested the cement facility's use of hazardous waste, but the company said the decision to phase it out was purely financial.
Mr. Parker said Ash Grove remains convinced of the usefulness of burning hazardous waste as fuel. It conserves fossil fuel while safely burning harmful substances, he said.
Ash Grove will continue to use hazardous waste fuel at two of its eight facilities, in Chanute, Kan., and Foreman, Ark. It already uses scrap tires at its plants in Durkee, Ore., and Inkon, Idaho, and is evaluating their use at its Seattle facility.
Using scrap tires to fuel cement kilns is a rapidly growing trend, according to Michael Blumenthal, executive director of the Scrap Tire Management Council.
``In 1991, two cement plants used scrap tires,'' Mr. Blumenthal said. ``Now, there are 30 that do, and there should be 45 by the end of this year.''
Not all plants which use scrap tires use them in every kiln, he added, but as they add kilns to that process, that means productive use of up to 1 million scrap tires annually.
Hazardous waste remains a very viable fuel for cement kilns, and initially it is more economical than scrap tires, according to Mr. Blumenthal.
Hazardous waste generators pay cement makers $80-$100 per ton to take their waste, whereas scrap tire generators pay only $15-$35 per ton.
But accidents with hazardous waste at cement kilns have caused fines and public outcry for some users. Also, according to Mr. Blumenthal, scrap tires are superior to either hazardous waste or conventional fuels for cement kilns.
``Tires burn better and cleaner than coal, and the metal can be recycled into the clinker (material used to make cement),'' he said. ``They allow cement makers to save on coal, and the high heat tires give off actually improves the cement.''
Furthermore, cement kilns can use stockpiled tires, which higher-end recyclers-such as crumb rubber producers and retreaders-cannot. ``Cement kilns are the single best way to use the value and characteristics of scrap tires,'' Mr. Blumenthal said.