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Indirect Fired TDU

TD*X Invented Indirect TDUs & Currently Operates 3 Indirect TDUs

Full Scale TDU

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Direct Fired TDU

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Mixed Waste

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TD*X Indirect Fired Thermal Desorption Units

Commercial TDU at TSDF

TD*X owns and operates a full scale commercial TDU that is installed at a fully permitted treatment storage and disposal facility (TSDF). This unit provides best in class recycling and treatment of hazardous waste. The unit operates under a RCRA Part B permit that controls all of the recycling activities and provides permit required limits to contain and control all emissions and process residuals. The unit therefore also operates as a Verified Recycler for the legitimate recycling of hazardous secondary materials from petroleum refineries, petrochemical production, and similar manufacturing facilities. Two permit required compliance demonstration tests have been performed on this unit under the RCRA permit. Compliance with the EPA’s MACT EEE (triple E) emission limits was demonstrated with tested emissions many times below the regulatory thresholds. Strict Operating Parameter Limits (OPLs) have been adopted under the RCRA permit to assure continuous compliance with these important environmental protection standards. This TDU facility routinely recovers and recycles millions of gallons of oil per year to conserve our country’s limited resources. This TDU is installed at our customer’s facility to efficiently provide thermal desorption services to many different types and generators of materials.

Commercial TDUs at Petroleum Refineries

Full scale commercial TD*X units have been and are presently installed at large oil refineries. These units provide best in class recycling for hazardous secondary materials that are generated in the oil refining process. Our TDUs have documented sustained operations recycling over 200 tons/day of refinery tank bottom solids; more than three times greater production than our next closest competitor in this application. This large capacity allows the host refinery to efficiently schedule tank management operations. The residual solids product from the TDU has all of the oil removed and recovered, and the organic chemical compounds are also removed to well below 1 ppm. We have worked with our host refinery partner to secure an EPA delisting of the desorber solids residual from our unit.

Warren County PCB Landfill Detoxification Project – Description

TD*X had extensive project responsibilities for the Warren County Landfill cleanup. PCB and dioxin contaminated soils were treated with a high capacity indirect thermal desorption unit. This unit has an industry leading production capacity of 20 to 50 ton/hr. It is a true indirect TDU; the flue gases are completely separated from the waste and desorbed waste gases.

Soil treatment was performed to treat 82,000 tons of soil that were contaminated with polychlorinated biphenyls (PCBs). The site was a TSCA permitted landfill that was constructed by the State of North Carolina in the early 1980s. Soil from the illegal disposal of PCB oil on State roads was placed in the landfill when NCDOT cleaned up the contaminated roadways. State law required on-site detoxification and closure of the landfill in response to environmental justice litigation brought by Warren County residents. The State required remediation by indirect thermal desorption of the soil followed by destruction of the organic condensate in a stirred tank reactor using the patented Base Catalyzed Decomposition (BCD) process. The State specification required treatment of the soil to 0.2 ppm PCBs, or a factor of 10 below that required by similar national standards and operating permits. The soil treatment was performed from August 2002 through October 2003.

TD*X Scope of Work
TD*X Associates, LLC was the treatment technology subcontractor for the Warren County project, with the following extensive project responsibilities:

    • prepare the detailed process design and the permit documents required to secure both the USEPA TSCA operating permit and the State air emissions permit,
    • perform off-site pilot testing to confirm the ability of the treatment process to meet the demanding project requirements,
    • prepare the detailed equipment drawings required to modify the processing equipment for the project, making it suitable for operation on PCB and dioxin contaminated soil,
    • provide the detailed design to construct the liquid BCD reactor subsystem,
    • direct the modification and construction of the equipment, both at the shop facility and at the project site,
    • direct the pre-test and full three-run performance demonstration tests and prepare comprehensive test reports required by the project and permits,
    • provide thermal treatment system operating personnel, including the Thermal Engineer, Site Engineer and Lead Plant Operators for the duration of the project, with responsibility for operation of the treatment equipment and meeting the stringent requirements of the State performance specification.

Project Results
The total project value was $14 million. The project was completed on schedule, and at a cost $3.5 million lower than the next qualified bidder. The indirect heated thermal desorption system operated at sustained treatment rates up to 21 ton/hr, faster than any other treatment unit of its type in the world.

The project average PCB level in the treated soil was 0.137 ppm. The demonstrated system equivalent DRE for PCBs ranged from 99.999999% to 99.9999999% (i.e. “eight-nines” to “nine-nines”); 100 to 1000 times more efficient than required by the PCB treatment permit. Based on the results of the TSCA demonstration, USEPA is issuing a national mobile operating permit for the thermal desorption unit. About 4,500 gallons of concentrated PCB oil was condensed and recovered and ultimately disposed of.

North Carolina Department of Environment and Natural Resources, Division of Waste Management.

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Contact TD*X Associates LP

TD*X is a technology development firm providing low temperature thermal desorption services for over 35 years and thus being the world leader in thermal desorption technology. Contact us for more information on our services. 


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