Prototype scale demonstration of CECE detritiation

AECL has developed and demonstrated the Combined Electrolysis and Catalytic Exchange (CECE) Process for detritiation of heavy water. Although CECE has been the subject of pilot-scale demonstrations by various organizations, AECL is the first to demonstrate this technology in an industrial prototype plant. AECL designed, built and operated a CECE demonstration facility under CAN/CSA N286 Quality Assurance Program. The facility was licensed by the Canadian nuclear regulator. This was a two-fold demonstration of the CECE technology - for upgrading (removal of light water) and for detritiation of heavy water. In 1998 June, AECL began operating the facility in upgrading mode. The design feed rate ranged up to 25 Mg/a for 95 mol% D2O feed water. After 18 months of operation in upgrading mode, the facility was reconfigured and operated for an additional 9 months from 2000 August in detritiation mode. Design capacity for detritiation was 5 Mg/a with a detritiation factor (DF) of 100. However, significantly higher DFs, up to 56 000, were demonstrated. Highlights of the detritiation demonstration were: Proven robustness of AECL's proprietary wetproofed catalyst for Liquid Phase Catalytic Exchange; Demonstration of a trickle-bed-recombiner for stoichiometric combination of deuterium and oxygen; Demonstration of electrolysis of highly tritiated heavy water; High process availability and controllability was demonstrated by a long interrupted run; Low emissions; Demonstration of high DF - up to 56 000 - a significant advantage of the CECE process over other approaches to detritiation; Validation of AECL's simulation code for the CECE process over a range of DFs from 100 to 50 000. Apart from the technology, AECL has expertise in all aspects of setting up a new detritiation facility including design, engineering, safety assessment, licensing support, project management and training. AECL is also the engineering and design contractor for a tritium removal facility that is under construction at Wolsong, Korea. AECL has the demonstrated technology, engineering and project management skills for new detritiation facilities. AECL is currently collaborating with ICSI, Rm. Valcea, and closely working with Mr. Stefan Liviu, Head of Pilot Plant, to develop a proposal for feasibility study of a detritiation facility for CANDU reactors at Cernavoda. (authors)