Overview of the Korean Nuclear Fuel Cycle and Recovered Uranium Fuel Program in Korea

Since Kori Uint 1 started to generate electricity on April 29, 1978, the nuclear share of the total electricity generation rate has continued to rise to the current value of 40.3% as of the end of 2006 in Korea. The average availability of the Kore an NPPs for the last 8 years ranges around 90% and ranked highly in the world for the past 3 years . However due to the delicate situation that Korean Penninsula faces, the nuclear fuel cycle program ha s neither been that much ambitious nor successful for the past few decades. As closed fuel cycles usi ng a wet process has not been possible, alternative proliferation-resistant nuclear fuel technology suc h as DUPIC has been developed and a series of irradiation tests are being carried out at the HANA RO reactor. As Korea has not only PWRs as a major vehicle but also CANDUs as minor vehicle, a s ymbiotic fuel cycle linking PWRs and CANDUs is quite attractive as an supplementary option besi des the PWR-SFR linkage concept via a pyroprocess. Another viable symbiotic option is the use of recovered uranium (RU), in CANDUs. Current direct disposal of PWR spent fuel option i s expectd to result in a steep rise of the spent fu el accumulation reaching 70,000 ton by 2100, but with the fuel recyle based on SFRs, it is expected to reduce to 4,000 ton. In the case of the RU program, the fissile of 0.9 to 1.0% makes it possible for a reuse in CANDU without a re-enrichment. Using RU fu el would produce a significant increase in the fuel discharge burnup of about twice that of NU in a CANDU reactor, thereby increasing the resource utilization and reducing the fuel requirements. Spe nt fuel volumes and fuelling costs are also reduced by using RU in CANDU reactors. Therefore, the use o f RU in CANDU reactors potentially offers economic, environmental and public acceptance benef its for both the front-end and back-end fuel cycles. The major carrier of the RU fuel for CANDU is 43-element CANFLEX, 24 NU bundles of which has already been irradiated in Wolsong for de monstration purpose. The changes in the fuel element and fuel bundle design from 37 to 43 elemen t bu dle contribute to the many advantages offered by the 43 CANFLEX bundle.