Partitioning planning studies: Preliminary evaluation of metal and radionuclide partitioning the high-temperature thermal treatment systems

A preliminary study of toxic metals and radionuclide partitioning during high-temperature processing of mixed waste has been conducted during Fiscal Year 1996 within the Environmental Management Technology Evaluation Project. The study included: (a) identification of relevant partitioning mechanisms that cause feed material to be distributed between the solid, molten, and gas phases within a thermal treatment system; (b) evaluations of existing test data from applicable demonstration test programs as a means to identify and understand elemental and species partitioning; and, (c) evaluation of theoretical or empirical partitioning models for use in predicting elemental or species partitioning in a thermal treatment system. This preliminary study was conducted to identify the need for and the viability of developing the tools capable of describing and predicting toxic metals and radionuclide partitioning in the most applicable mixed waste thermal treatment processes. This document presents the results and recommendations resulting from this study that may serve as an impetus for developing and implementing these predictive tools

Development of a method utilizing drum headspace VOC concentration as a waste characterization tool

Pretest waste characterization for the bin-scale tests at the Waste Isolation Pilot Plant (WIPP) required sampling for volatile organic compounds (VOCS) from within transuranic (TRU) waste drums. Although the bin-scale tests have been postponed, the development and demonstration of accurate waste characterization methods continues. The objectives of extensive sampling of waste drums are to obtain a representative sample from each layer of confinement to identify volatile and gaseous constituents, verify process knowledge of the drum contents, and demonstrate compliance with regulatory requirements. A method to estimate the VOC concentration between layers of confinement from a single headspace sample collected beneath the drum filter of a vented waste drum is investigated. This method of characterizing the void space within a drum could eventually lead to a significant reduction in sampling time and cost. A model based on fundamental principles of transport phenomena is developed to estimate the VOC concentration throughout a waste drum based on the knowledge of the transport properties and the measured drum headspace VOC concentration. Model and experimental results are compared

Los Alamos National Laboratory Develops ''Quick to WIPP'' Strategy

The Cerro Grande forest fire in May of 2000 and the terrorist events of September 11, 2001 precipitated concerns of the vulnerability of legacy contact-handled (CH), high-wattage transuranic (TRU) waste stored at Los Alamos National Laboratory (LANL). An analysis of the 9,100 cubic meters of stored CH-TRU waste revealed that 400 cubic meters or 4.5% of the inventory represented 61% of the risk. The analysis further showed that this 400 cubic meters was contained in only 2,000 drums. These facts and the question ''How can the disposition of this waste to the Waste Isolation Pilot Plant (WIPP) be accelerated?'' formed the genesis of LANL's Quick to WIPP initiative

Mapping the fragmentation of acetylene with femtosecond resolution pump probe at LCLS using 2, 3, and 4 particle coincidences.

A three-layer delay line anode detector has been used in x-ray pump x-ray probe time-resolved measurement at LCLS. We used ~10 fs long pulses to initiate and probe ultrafast dynamics in the dication of acetylene. The dynamics are discerned from the temporal evolution of multi-particle coincidences

Measurement of VOC permeability of polymer bags and VOC solubility in polyethylene drum liner

A test program conducted at the Idaho National Engineering Laboratory (INEL) investigated the use of a transport model to estimate the volatile organic compound (VOC) concentration in the void volume of a waste drum. Unsteady-state VOC transport model equations account for VOC permeation of polymer bags, VOC diffusion across openings in layers of confinement, and VOC solubility in a polyethylene drum liner. In support of this program, the VOC permeability of polymer bags and VOC equilibrium concentration in a polyethylene drum liner were measured for nine VOCs. The VOCs used in experiments were dichloromethane, carbon tetrachloride, cyclohexane, toluene, 1,1,1-trichloroethane, methanol, 1,1,2-trichloro-1,2,2-trifluoroethane (Freon-113), trichloroethylene, and p-xylene. The experimental results of these measurements as well as a method of estimating both parameters in the absence of experimental data are described in this report

VOC transport in vented drums containing simulated waste sludge

A model is developed to estimate the volatile organic compound (VOC) concentration in the headspace of the innermost layer of confinement in a lab-scale vented waste drum containing simulated waste sludge. The VOC transport model estimates the concentration using the measured VOC concentration beneath the drum lid and model parameters defined or estimated from process knowledge of drum contents and waste drum configuration. Model parameters include the VOC diffusion characteristic across the filter vent, VOC diffusivity in air, size of opening in the drum liner lid, the type and number of layers of polymer bags surrounding the waste, VOC permeability across the polymer, and the permeable surface area of the polymer bags. Comparison of model and experimental results indicates that the model can accurately estimate VOC concentration in the headspace of the innermost layer of confinement. The model may be useful in estimating the VOC concentration in actual waste drums

Flammability Assessment Methodology Program Phase I: Final Report

The Flammability Assessment Methodology Program (FAMP) was established to investigate the flammability of gas mixtures found in transuranic (TRU) waste containers. The FAMP results provide a basis for increasing the permissible concentrations of flammable volatile organic compounds (VOCs) in TRU waste containers. The FAMP results will be used to modify the ''Safety Analysis Report for the TRUPACT-II Shipping Package'' (TRUPACT-II SARP) upon acceptance of the methodology by the Nuclear Regulatory Commission. Implementation of the methodology would substantially increase the number of drums that can be shipped to the Waste Isolation Pilot Plant (WIPP) without repackaging or treatment. Central to the program was experimental testing and modeling to predict the gas mixture lower explosive limit (MLEL) of gases observed in TRU waste containers. The experimental data supported selection of an MLEL model that was used in constructing screening limits for flammable VOC and flammable gas concentrations. The MLEL values predicted by the model for individual drums will be utilized to assess flammability for drums that do not meet the screening criteria. Finally, the predicted MLEL values will be used to derive acceptable gas generation rates, decay heat limits, and aspiration time requirements for drums that do not pass the screening limits. The results of the program demonstrate that an increased number of waste containers can be shipped to WIPP within the flammability safety envelope established in the TRUPACT-II SARP

WERF MACT Feasibility Study Report

This study was undertaken to determine the technical feasibility of upgrading the Waste Experimental Reduction Facility (WERF) at the Idaho National Engineering and Environmental Laboratory to meet the offgas emission limits proposed in the Maximum Achievable Control Technologies (MACT)rule. Four practicable offgas treatment processes were identified, which, if installed, would enable the WERF to meet the anticipated MACT emission limits for dioxins and furans (D/F), hydrochloric acid (HCI), and mercury (Hg). Due to the three-year time restraint for MACT compliance, any technology chosen for the upgrade must be performed within the general plant project funding limit of $5 M. The option selected consists of a partial-quench evaporative cooler with dry sorbent injection for HCI removal followed by a sulfur-impregnated activated carbon bed for Hg control. The planning cost estimate for implementing the option is$4.17 M (with 24% contingency). The total estimated cost includes capital costs, design and construction costs, and project management costs. Capital costs include the purchase of a new offgas evaporative cooler, a dry sorbent injection system with reagent storage, a new fabric filter baghouse, a fixed carbon bed absorber, and two offgas induced draft exhaust fans. It is estimated that 21 months will be required to complete the recommended modification to the WERF. The partial-quench cooler is designed to rapidly cool the offgas exiting the secondary combustion chamber to minimize D/F formation. Dry sorbent injection of an alkali reagent into the offgas is recommended. The alkali reacts with the HCI to form a salt, which is captured with the fly ash in the baghouse. A design HCI removal efficiency of 97.2% allows for the feeding 20 lbs/hr of chlorine to the WERF incinerator. The sorbent feed rate can be adjusted to achieve the desired HCI removal efficiency. A fixed bed of sulfur-impregnated carbon was conservatively sized for a total Hg removal capacity when feeding 10 g/hr Hg to the WERF incinerator. An added benefit for using carbon adsorption is that the activated carbon will also capture a large fraction of any residual D/F present in the offgas

Method of characterizing void volume headspace in vented transuranic waste sludge drums using limited sampling data

The Department of Energy must demonstrate to the Environmental Protection Agency that a drum headspace sample is representative of the volatile organic compounds (VOCs) within the entire void space of the waste container in order to demonstrate compliance in the future when drums could be directly emplaced in the Waste Isolation Pilot Plant in New Mexico. A test program is underway at the Idaho National Engineering Laboratory to determine if the drum headspace VOC concentration is representative of the concentration in the entire drum void space and demonstrate that the VOC concentration in the void space of each layer of confinement can be estimated using a model incorporating diffusive and permeative transport principles and limited waste drum sampling data. A comparison of model predictions of VOC concentration in the innermost layer of confinement with actual measurement from transuranic waste sludge drums demonstrate that the model may be useful in characterizing VOC concentration throughout entire drum void volume

Modeling unsteady-state VOC transport in simulated waste drums. Revision 1

This report is a revision of an EG&G Idaho informal report originally titled Modeling VOC Transport in Simulated Waste Drums. A volatile organic compound (VOC) transport model has been developed to describe unsteady-state VOC permeation and diffusion within a waste drum. Model equations account for three primary mechanisms for VOC transport from a void volume within the drum. These mechanisms are VOC permeation across a polymer boundary, VOC diffusion across an opening in a volume boundary, and VOC solubilization in a polymer boundary. A series of lab-scale experiments was performed in which the VOC concentration was measured in simulated waste drums under different conditions. A lab-scale simulated waste drum consisted of a sized-down 55-gal metal drum containing a modified rigid polyethylene drum liner. Four polyethylene bags were sealed inside a large polyethylene bag, supported by a wire cage, and placed inside the drum liner. The small bags were filled with VOC-air gas mixture and the VOC concentration was measured throughout the drum over a period of time. Test variables included the type of VOC-air gas mixtures introduced into the small bags, the small bag closure type, and the presence or absence of a variable external heat source. Model results were calculated for those trials where the permeability had been measured