Investigation of thermolytic hydrogen generation rate of tank farm simulated and actual waste

Assessment of Methane Generation from the Thermolysis of Organics in Caustic Waste

“…31 Methane generation was detected during HGR testing on Tank 38 waste and a high boiling point (HBP) simulant, as shown by the red dots in Figure 2-4. 1 Due to experimental limitations during the HBP simulant test, a methane generation rate could not be determined quantitatively from this study. From previous speciation testing of mercury in Tank 38, the concentrations of methylmercury and dimethylmercury were 160-200 mg/L and 0.0525-0.148 mg/L respectively.…”

“…Revision 0 vii [1][2][3][4] Methane was also detected in further thermolytic HGR testing, specifically with simulants containing trimethylsilanol (TMS). 1,5 This evidence of thermolytic methane generation prompted the authoring of the report, Evaluation of the Current State of Knowledge for Thermolysis of Organics within SRS Waste Forming Volatile Organic Compounds (VOCs). 6 That review assessed the current knowledge of VOCs from thermolysis in organics in SRS caustic tank waste, recommending further experiments to measure the methane generation rate.…”

“…In HGR radioactive waste testing, methane was detected in samples at elevated temperatures for Tanks 28, 38, and 44. [1][2][3][4] Volatile organic analysis (VOA) of the Tank 44 samples found 0.9 mg/L of octamethylcyclotetrasiloxane. 4 Octamethylcyclotetrasiloxane is possibly a degradation product or impurity of antifoam H-10, a polydimethylsiloxane-based antifoam that was formerly used in Concentration, Storage and Transfer Facility (CSTF) evaporators.…”

Evaluation of Thermolytic Production of Hydrogen from Glycolate and Common Tank Farm Organics in Simulated Waste

“…The apparatus consisted of a 1.2 L polytetrafluoroethylene (PTFE) kettle sealed with a PTFE lid. PTFE was identified as the preferred material of construction due to the observation in previous testing 11 that glass vessels tend to react with higher hydroxide loadings to form sodium aluminosilicates. The center of the lid was fit with a magnetic drive from Parr Instrument Company.…”

“…Note that the expressions given in Equations [9] through [11] inherently rely on a few assumptions. First, these expressions assume that only the components shown (aluminum, nitrite, nitrate, hydroxide, sulfate, carbonate, and sodium) have a meaningful impact on thermolytic HGR from glycolate.…”