초록 ▼

2016년까지, ‘PRIDE/ ACPF 운전과 개량을 통한 공학규모 파이로 전해환원 모의 실증기술과 실험실 규모 파이로 전해환원장치 실증기술 및 공정장치 혁신기술 개발’, 이라는 목표를 달성하기 위하여, 본 과제에서는 1단계 (2012 - 2014) 연구기간 동안에 PRIDE/ACPF 시험체계 구축 및 공정시험을 수행하고 고용량 전해환원 핵심기술을 개발하여 왔음. PRIDE 전해환원 공정장치 설치 후 blank test 및 염 장입 (400 kg) 및 U 이용 전해환원 시험 수행을 통해 장치 성능을 검증하고 개선사항을 도출함. AC

2016년까지, ‘PRIDE/ ACPF 운전과 개량을 통한 공학규모 파이로 전해환원 모의 실증기술과 실험실 규모 파이로 전해환원장치 실증기술 및 공정장치 혁신기술 개발’, 이라는 목표를 달성하기 위하여, 본 과제에서는 1단계 (2012 - 2014) 연구기간 동안에 PRIDE/ACPF 시험체계 구축 및 공정시험을 수행하고 고용량 전해환원 핵심기술을 개발하여 왔음. PRIDE 전해환원 공정장치 설치 후 blank test 및 염 장입 (400 kg) 및 U 이용 전해환원 시험 수행을 통해 장치 성능을 검증하고 개선사항을 도출함. ACPF 전해환원 장치(1kg/batch)를 설계/제작하여 목업시험 시설에서 우라늄 및 모의실증연료를 이용하여 검증함으로써 핫셀 금속전환 실험을 대비한 연구를 수행하고 핫셀에 동일 장치를 설치, 시운전함. 대체 양극/재료/염/측정기술 개발을 통해 전해환원 공정장치의 장기안정성과 경제성 제고하는데 기여하고, 단위공정 모델개발을 통해 전산모사 기반을 확립하였음. 또한 배치당 50 kg 이상의 전해환원 시스템 규모 확대 가능성을 시험하기 위한 다전극 병렬모듈형 전해환원장치를 제작, 시험하여 고효율/고용량 단위공정 혁신공정장치 개발 기반을 마련함.

(출처 : 보고서 요약서 3p)

Abstract ▼

IV. Results of the Project
The PRIDE/ACPF electrolytic reduction system has been tested and evaluated. After the remote operation of engineering scale PRIDE electrolytic system (50 kgU/batch) in PRIDE Ar cell was successfully completed, the salt and U tests were carried out. U tests using mock-u

IV. Results of the Project
The PRIDE/ACPF electrolytic reduction system has been tested and evaluated. After the remote operation of engineering scale PRIDE electrolytic system (50 kgU/batch) in PRIDE Ar cell was successfully completed, the salt and U tests were carried out. U tests using mock-up ACPF electrolytic reducer (1 kgU/batch) were also successfully performed to prepare ACPF hot test. As key technologies for electrolytic reduction commercialization, a modular parallel electrolytic reduction system, alternative anode/salt/material/monitoring and unit process equipment simulation models have been developed.

1. Tests of the PRIDE electrolytic reduction system
The PRIDE electrolytic system consists of electrolytic reducer, electrolytic reduction cathode processor and rotation equipment. The function of the electrolytic reducer is to electrically convert oxide fuel to metallic product. The function of the cathode processor is to remove residual salt in the metal product of electrolytic reduction by distillation. Rotation equipment is used for the remote and automated operation of the electrolytic reducer and the cathode processor, and can handle vessels and baskets with various shapes and dimensions using motors.

After the PRIDE electrolytic system (50 kgU/batch) was installed in PRIDE Ar cell, the entire remote operation tests were performed according to the operation procedure of electrolytic reduction process. After the remote operation tests, modifications (or change) of several components (the anode ports, heat shields and gas outlet system of top flange, anode shroud material and bolting-up method etc.) of the PRIDE electrolytic reducer were determined and performed.

LiCl salt (400 kg) for the PRIDE electrolytic reducer was dehydrated through melting and cooling it under vacuum condition. It was proved that the level of moisture in the prepared LiCl ingot was dramatically reduced (2000 → ∼20 ppm). While the dehydrated LiCl salt of the pre-determined mass was successively loaded and melted in the PRIDE electrolytic reducer, the salt levels were measured using radar sensor and dipstick technique. The calibration data between salt mass and level was obtained using the results.

Salt was successfully evaporated and recovered using the electrolytic reduction cathode processor. The performance of the PRIDE electrolytic reducer was tested using titanium oxide (TiO₂) and uranium oxide (UO₂). After the preliminary reduction test using TiO₂, its reduction product was confirmed. U metals were obtained through two electrolytic reduction runs of UO₂ (5kgUO₂/batch). While the LiCl salt had been melted without cooling for more than 60 days, it was revealed that the heat shield and Pt anode of PRIDE electrolytic reducer did not show a significant damage. However, several improvement measures such as the speed of electrolytic reduction and the control of the Pt corrosion by the elements from the stainless steel and inconel material were determined. Thus, the optimization of the PRIDE electrolytic reducer　operation will be carried out in the second phase of this project. 　

2. Development of electrolytic reduction commercialization technology
· Modular parallel electrolytic reduction system
- Modular parallel electrolytic reduction system (∼1kgUO₂/batch) was designed and fabricated. The effects of the cathode/anode area ratio, the electrode configuration and shape on the reduction performance were investigated. Also, the experimental results were compared with those of the simulation.
· Alternative anode/salt/material/monitoring technology
- Several alternative anode materials (graphite, Sb, Nb:SrTiO₃, IrO₂-Ta₃O₇, SrRuO₃, TiN and La_0.33Sr_0.67MnO₃) were selected and evaluated through bench-scale electrolytic reduction experiments. While successful reduction products were obtained using graphite and La_0.33Sr_0.67MnO₃ anodes, it was revealed that Sb, Nb:SrTiO₃, IrO₂-Ta₃O₇, SrRuO₃ and TiN did not show a good stability under the electrolytic reduction condition. In the second phase of this project, the long-term stability and optimization tests will be carried out using graphite and La_0.33Sr_0.67MnO₃ anodes.
- MgO stabilized zirconia shows good chemical and mechanical stabilities during the electrolytic reduction runs.
- On-line monitoring using radar sensor was adopted and successfully used in PRIDE electrolytic reducer after a preliminary test in lab-scale.
· Development of unit process equipment simulation model
- It was predicted that the cell current consistently decreases with the distance between anode and cathode. Also, the total current in multi set experiments was in proportion to the number of electrode sets. The simulation results revealed that the total current increased proportionally for every each addition of anode 1 set with 2 anodes.

3. ACPF electrolytic reduction test
ACPF electrolytic reducer (1 kgU/batch) were designed and fabricated. Its performance was evaluated and modified through the mock-up test using UO₂ and simfuel (simulated fuel). After the electrolytic reduction runs conducted in a series, the reduction products with high reduction conversion rates (>99%) were obtained. Also, the amount of the residual salt in the metal product was dramatically reduced using the salt separation above the interface between the salt and gas at 650 ℃. After the ACPF electrolytic reducer was installed in Ar cell of hot cell, the heating test was successfully conducted.

(출처 : SUMMARY 11p)

목차 Contents

• 표지 ... 1
• 제 출 문 ... 2
• 보고서 요약서 ... 3
• 요 약 문 ... 4
• SUMMARY ... 10
• CONTENTS ... 14
• 목차 ... 15
• 표목차 ... 16
• 그림목차 ... 18
• 제1장 사용후핵연료 전해환원 기술개발 과제 개요 ... 31
• 제2장 국내외 기술개발 현황 ... 33
• 제 1 절 산화물 사용후핵연료 금속전환 기술 ... 33
• 제3장 사용후핵연료 전해환원 기술개발 수행내용 및 결과 ... 37
• 제 1 절 PRIDE 전해환원 공정장치 성능평가 및 개량 ... 37
• 1. PRIDE 전해환원 시험체계 구축 (blank test) ... 37
• 2. PRIDE 전해환원장치 시운전 및 공정장치 개량 ... 55
• 3. PRIDE 전해환원 공정시험 (공정장치 성능평가) ... 63
• 제 2 절 고용량 전해환원 핵심기술 시험 ... 99
• 1. 병렬 모듈형 전해환원 시스템 개발 ... 99
• 2. 전해환원 단위공정 모델 개발 및 전산모사 ... 133
• 3. 전해환원 대체 양극/염/재료/측정기술 분석 및 특성평가 ... 172
• 제 3 절 ACPF 전해환원 공정시험 ... 240
• 1. ACPF 전해환원 실증장치 설계도 생산 및 제작 ... 240
• 2. ACPF 전해환원 실증장치 개량 및 시운전/원격성 평가 ... 246
• 3. ACPF 종합 시운전 평가 ... 265
• 제4장 목표달성도 및 관련분야에의 기여도 ... 284
• 제5장 연구개발결과의 활용계획 ... 285
• 제6장 연구개발과정에서 수집한 해외과학기술정보 ... 286
• 제7장 참고문헌 ... 287
• 끝페이지 ... 288