Process Development for Destruction of Hazardous Organic Compounds Including Halogens, Phosphate Esters, or Other Intractable MoitiesEPA Contract Number: 68D00238
Title: Process Development for Destruction of Hazardous Organic Compounds Including Halogens, Phosphate Esters, or Other Intractable Moities
Investigators: Howell, Samuel G.
Small Business: Excell Partnership
EPA Contact: Manager, SBIR Program
Project Period: September 1, 2000 through March 1, 2001
Project Amount: $69,713
RFA: Small Business Innovation Research (SBIR) - Phase I (2000) RFA Text | Recipients Lists
Research Category: Hazardous Waste/Remediation , SBIR - Waste , Small Business Innovation Research (SBIR)
Description:A new approach to destroying polychlorinated biphenyl (PCB), pesticides, toxic organic compounds, and obsolete chemical weaponry overcomes many of the objections to previous methods. Incineration of these compounds is thermally inefficient and often produces highly toxic by-products such as dioxins and furans. Conventionally, molten salt oxidation requires high temperatures and precautions to minimize corrosion of the operating equipment. Dehalogenation approaches such as the BCD process are effective at low concentrations (below 10-15 percent), but are ineffective at high concentrations of PCB, as they produce a waste gummy by-product that must be disposed of, as such products might fall under the EPA "Derived From" rule. This Phase I project uses a new process that is unique; it utilizes a patented eutectic mixture of highly oxidizing molten salts and operates effectively at much lower temperatures than previous molten salt reactors. The mixture is inexpensive, almost noncorrosive, and has a low viscosity that allows it to be pumped into a multistage contactor, thus essentially allowing the operator to achieve any degree of destruction desired. If compounds containing halogen, phosphate, or sulfate groups are treated, the corresponding salts form precipitate, and can be separated from the melt, allowing most to be reused. The reaction is highly exothermic, as oxidation of the hydrocarbon fraction and the formation of the sodium salts produce heat that may be recovered by conventional heat recovery equipment. Laboratory results indicate extremely high degrees of destruction of simulants for PCB, pesticides, and chemical warfare agents. Successful laboratory results have prompted the developers to seek funds to build a larger reactor that will allow them to determine destruction efficiencies for various compounds, and develop capital costs for commercial units.
A scaleup of Excell Partnership's laboratory reactor will confirm that the present design of gas/liquid contacting apparatus for the Wabash process can lead to production of commercial units for the destruction of many hazardous wastes such as drycleaning sludges, waste paints, pesticides, and obsolete chemical weaponry. Successful operation of a larger reactor for an extended period will enable more accurate estimation of the capital and operating costs of such a full-scale plant. Operation of a larger reactor also will yield more data about exothermic heat evolution and heat losses. This will be useful in designing heat removal apparatus in a full-scale reactor. Because reagent costs for the process are almost fixed, except for the small amount of nitrate carried out with the precipitated salts, a larger reactor equipped with continuous precipitate removal will allow Excell Partnership to determine the quantity and include it in the variable costs.