Battelle Energy Alliance, LLC, has demonstrated the effectiveness of the hot isostatic press (HIP) process for treatment of hazardous high-level waste known as calcine that is stored at the Idaho Nuclear Technology and Engineering Center (INTEC) at Idaho National Laboratory. HIP trials performed with simulated calcines at Idaho National Laboratory's Materials and Fuels Complex and an Australian Nuclear Science and Technology Organization facility from 2007 to 2010 produced a dense, monolithic waste form with increased chemical durability and effective (storage) volume reductions of ~10 to ~70% compared to granular calcine forms. In December 2009, the U.S. Department of Energy signed an amended Record of Decision selecting HIP technology as the treatment method for the 4,400 m 3 of granular zirconia and alumina calcine stored at INTEC. Testing showed that HIP treatment reduces the risks associated with radioactive and hazardous constituent release, post-production handling, and long-term (repository) storage of calcines and would result in estimated storage cost savings in the billions of dollars. Battelle Energy Alliance has the ability to complete pilot-scale HIP processing of INTEC calcine, which is the next necessary step in implementing HIP processing as a calcine treatment method.

Trapping experiments have been performed at the Idaho National Laboratory to assess the performance of AgX sorbent media in capturing volatile iodine during the oxidation of irradiated oxide fuel. The demonstration of iodine release and capture from the used fuel has been accomplished with laboratory-scale equipment in a hot cell environment. Iodine loadings as high as 6 ug/g media have been achieved via chemical adsorption with filter efficiencies in excess of 90%. In addition to iodine, significant quantities of tritium have also been collected on the AgX filter media. Filter media loaded with radioactive iodine has been sequestered in a tin matrix by hot isostatic pressing at 200°C. The placement and encapsulation of the sorbent media was examined by neutron radiography, thus confirming the sequestration of radioactive iodine.

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Voloxidation is a potential process used to prepare fuel for spent-oxide-fuel treatment. The spent oxide fuel is heated to an elevated temperature in oxygen or air to promote separation of the fuel from the cladding. Low pressures are also required to enhance volatizing the fission products. The Idaho National Laboratory and the Korea Atomic Energy Research Institute have been collaborating on voloxidation research through a joint International Nuclear Energy Research Initiative project. The new high temperature multiple zone furnace and off-gas trapping system (OTS) are designed for remote operation in the Hot Fuel Examination Facility. The OTS is designed to handle vacuum, oxidizing environments, and high temperatures. Distinctive temperature zones of the furnace are used to selectively capture the fission products. Vacuum conditions at elevated temperatures are achieved by incorporating various metal seals. The OTS has proved durable under these aggressive operating conditions. A detailed description of the second generation furnace and OTS with enhanced capabilities will be presented. INTRODUCTIONIdaho National Laboratory (INL) and the Korea Atomic Energy Research Institute (KAERI) have been investigating an advanced head-end processing concept to declad and oxidize (DEOX) spent oxide nuclear fuels. The objective of the DEOX process is to achieve separation of the spent fuel from the cladding. The feed material is spent fuel from light water reactor uranium oxide (UO 2 ) or fast reactor mixed oxide (MOX). Remote tools are used to cut the spent fuel into shorter segments that fit within the operating envelope. The main pieces of equipment are used to heat the segments in an oxygen-rich environment and to collect the off-gas fission

Battelle Energy Alliance, LLC, has successfully tested a remote welding process to seal radioactive waste containers prior to hot isostatic pressing (HIP). Since the 1990s, a variety of radioactive and hazardous waste forms have been remotely treated using HIP during trials within Idaho National Laboratory (INL) hot cells. For HIP treatment at INL, waste was loaded into a stainless-steel or aluminum canister, which was evacuated, seal welded, and placed in a HIP furnace. HIP simultaneously heats and pressurizes the waste, reducing its volume and increasing its stability, thus lowering the cost and risk associated with disposal. Weld integrity must be ensured in order to prevent the spread of contamination during HIP. This paper presents a process for sealing HIP canisters remotely using modified, commercially available equipment. This process includes evacuation, heating, welding, and weld inspection. The process and equipment have proven to reliably seal canisters in continued HIP trials.