Superfund Innovative Technology Evaluation (SITE)
Note: EPA no longer updates this information, but it may be useful as a reference or resource.
This report evaluates the Horsehead Resource Development Company, Inc. (HRD), Flame Reactor technology's ability to remove and recover volatile metals such as lead and zinc from waste while producing a vitrified slag that meets applicable disposal requirements. This report presents economic data from the U.S. Environmental Protection Agency Superfund Innovative Technology Evaluation (SITE) demonstration and seven case studies.
The HRD Flame Reactor technology is a patented high-temperature thermal process designed to safely treat industrial residues and wastes containing metals. During processing, the waste material is introduced into the hottest portion of the HRD Flame Reactor, where wastes are subjected to a very hot (greater than 2000°C) reducing gas produced from the combustion of solid or gaseous hydrocarbon fuels in oxygen-enriched air. At these temperatures, volatile metals in the waste are vaporized and any organic compounds are destroyed. The waste materials react rapidly, producing a nonleachable slag and gases, including steam and metal vapors. Metal vapors further react and cool in the combustion chamber and cooling system, producing metal-enriched oxides that are collected in a baghouse. The resulting metal oxides can be recycled to recover the metals. The amount of waste reduced to slag and oxide depends on the chemical and physical properties of the waste material.
The HRD Flame Reactor technology demonstration was conducted as a part of the SITE program at the HRD facility in Monaca, Pennsylvania. For this demonstration, rotary-kiln, secondary lead smelter, soda slag was treated to produce a lead- and zinc-enriched metal oxide product and a nonhazardous effluent slag. Greater than 75 percent of the lead, cadmium, and zinc in the waste was recovered in the recyclable metal oxide product. Concentrations of lead and zinc in the oxide product were 17.4 and 1.38 percent, respectively. The effluent slag was determined to be nonhazardous based on extraction by the Toxicity Characteristic Leaching Procedure and subsequent chemical analysis of the extracts. The weight of the treated waste was reduced by 36.6 percent. During the demonstration, the Flame Reactor unit experienced no major operational problems. Several auxiliary systems had minor, repairable problems.
Potential wastes that might be treated by this technology include industrial residues, Resource Conservation and Recovery Act wastes, Superfund wastes, and other wastes contaminated with metals and organic compounds. A brief overview of the results from HRD Flame Reactor case studies, which discuss wastes that have been treated by the technology, is presented as an appendix to this report.
Economic data indicate that the cost of treating wastes similar to those treated in the HRD Flame Reactor SITE demonstration, including excavation and transportation to the HRD facility, pretreatment of the waste, and a credit of the metal oxides that are recovered, range from $208 to $932 per ton.