SummaryProcess development research is continuing at Pacific Northwest Laboratory on a low-temperature, catalytic gasification system that has been demonstrated to convert organics in water (dilute or concentrated) to useful and environmentally safe gases. The system, licensed under the trade name Thermochemical Environmental Energy System (TEESa), treats a wide variety of feedstocks ranging from hazardous organics in water to waste sludges from food processing. The current research program is focused on the use of continuous-feed, tubular reactors systems for testing catalysts and feedstocks in the process. A range of catalysts have been tested, including nickel and other base metals, as well as ruthenium and other precious metals.Results of extensive testing show that feedstocks, ranging from 2% para-cresol in water to potato waste and spent grain, can be processed to > 99% reduction of chemical oxygen demand (COD). The estimated residence time is about 10 min at 350°C and 21 MPa, not including about 3 min required in the preheating zone of the reactor. The liquid hourly space velocity varies from 1.0 to 4.8 L feedstocWL catalystlhr, depending on the feedstock. The product fuel gas contains from 40% up to 75 % methane, depending on the feedstock. The balance of the gas is mostly carbon dioxide with < 5 % hydrogen and usually < 1 % ethane and higher hydrocarbons. The byproduct water stream carries residual organics from 10 to 1000 mg1L COD, depending on the feedstock.

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DISCLAIMERPortions of this document may be illegible in electronic image products. Images are produced from the best available original document. SummaryThe main purpose of this work was to demonstrate the Dual Shell Pressure Balanced Vessel (DSPBV) as a safe and economical reactor for the hydrothermal water oxidation of hazardous wastes. Experimental tests proved that the pressure balancing piston and the leak detection concept designed for this project will work.The DSPBV was sized to process 10 gaVhr of hazardous waste at up to 399°C (750°F) and 5000 psia (34.5 m a ) with a residence time of 10 min. The first prototype reactor is a certified ASME pressure vessel. It was purchased by Innotek Corporation (licensee) and shipped to Pacific Northwest Laboratory (PNL) for testing. Supporting equipment and instnunentation were, to a large extent, transported here from Battelle Columbus Division. A special air feed system and liquid pump were purchased to complete the package. The entire integrated demonstration system was assembled at PNL.During the activities conducted for this report, the leak detector design was tested on bench top equipment. Response to low levels of water in oil was considered adequate to ensure safety of the pressure vessel.Shakedown tests with water only were completed to prove the system could operate at 35OOC at pressures up to 3300 psia. Two demonstration tests with industrial waste streams were conducted, which showed that the DSPBV could be used for hydrothermal oxidation. In the first test with a metal plating waste, chemical oxygen demand, total organic carbon, and cyanide concentrations were reduced over 90%. In the second test with a munitions .waste, the organics were reduced over 90% using H,O, as the oxidant.