Fluidized Bed Steam Reforming of INEEL SBW Using THORsm Mineralizing Technology

Abstract

Sodium-bearing waste (SBW) disposition is one of the U.S. Department of Energy (DOE) Idaho Operation Office's (NE-ID) and State of Idaho's top priorities at the Idaho National Engineering and Environmental Laboratory (INEEL). Many studies have resulted in the identification of five treatment alternatives that form a short list of perhaps the most appropriate technologies from which the DOE may select. The alternatives are (a) calcination with maximum achievable control technology (MACT) upgrade, (b) steam reforming, (c) cesium ion exchange (CsIX) with immobilization, (d) direct evaporation, and (e) vitrification. Each alternative has undergone some degree of applied technical development and preliminary process design over the past four years. DOE desired further experimental data, with regard to steam reforming technology, to make informed decisions concerning selection of treatment technology for SBW. Mineralizing steam reforming technology, offered by THOR Treatment Technologies, LLC would produce a denitrated, granular mineral waste form using a high-temperature fluidized bed process. A pilot scale demonstration of the technology was performed in a 15-cm-diameter reactor vessel September 27 through October 1, 2004. The pilot scale equipment is owned by the DOE, and located at the Science and Technology Applications Research (STAR) Center in Idaho Falls, ID. Flowsheet chemistry and operational parameters were defined through a collaborative effort involving Idaho National Engineering and Environmental Laboratory, Savannah River National Laboratory (SRNL), and THOR Treatment Technologies personnel. Personnel from Science Applications International Corporation, owners of the STAR Center, operated the pilot plant.The pilot scale test was terminated as planned after achieving a total of 100 hrs of cumulative/continuous processing operation. About 278 kg of SBW simulant mixed with clay additive were processed that resulted in about 88 kg of solid product that included starting bed material and unreacted carbon. The process achieved about a 90% turnover of the starting bed. Samples of mineralized solid product materials were analyzed for chemical/physical properties and processing data were collected for operational analyses. Results of product performance testing conducted by SRNL will be reported separately by SRNL. 4 EXECUTIVE SUMMARYThe US Department of Energy (DOE) desired further experimental data, with regard to fluidized bed steam reforming (FBSR) technology, to make informed decisions concerning the selection of treatment technology for Idaho National Engineering and Environmental Laboratory (INEEL) sodium-bearing waste (SBW). Experimental data from tests using actual radioactive waste were desired to provide the most beneficial information to DOE. It was recognized that there was not an experimental fluidized bed test system/facility available to generate experimental radioactive data in the desired time frame. Therefore, a collaboration involving laboratory work at Savannah River National Laborat...