Spent Fuel Management and Research Activities in Korea

33rd Spent Fuel Management Seminar (January 23 ~ 25, 2018, Alexandria, VA)

Woo-seok Choi

Director of RAM Transport and Storage Dep’t

2/22

Contents

DPC and Concrete Cask Development

Seismic Performance Evaluation Test and Analysis

Heat Removal Performance Test and Analysis

Aircraft Impact Test and Analysis

Metal Seal Accelerated Test

Analysis for Vibration and Shock Condition

1. Inventory of Spent Fuel in Korea

2. Traces of Efforts on SF Management in Korea

3. National Policy of HLW Management

4. Overview of Research and Development

5. Summary

3/22

I. Inventory of SF in Korea

4/22

499,632

Wolsong

430,576

Hanbit

9,017

6,034

Hanul

7,066

5,263

Kori

6,494

6,024

Shinwolsong

1,046 253

STORED(#FA)

CAPACITY(#FA)

Operation : 24 Construct : 5 Plan : 2

Hanbit

Hanul

Wol- song

Kori Hanbit

Hanul

Shin-Hanul

Wolsong

Shin-Wolsong

Kori

Shin-Kori

Site Location and Current SF Pool Status (as of 2017. June)

5/22

II`. Traces of Efforts on SF Management in Korea

6/22

Dec. 2004 : The 253rd Atomic Energy Commission(AEC)

• Decided that the project of HLW management should be carried out separately from

the that of LILW management • The LILW repository was sited in Nov. 2005 and complete it in Aug. 2015

1

Dec. 2009 : Legal ground for the public engagement

• Made to stipulate definition of the public engagement and function of the public

engagement commission in the Article 6.2 of RWMA

2

Apr. 2007~Aug. 2012 : Study and Research 3

• ON methods and procedures of public engagement and SNF management options

through the involvement of experts, NGOs and local residents

• TF for SNF Public engagement (Apr. ‘07~Jun. ’08), Experts’ study on technical

options for SNF management (Dec. ‘09~Aug. ’11), SNF Policy Forum (Nov.

‘11~Aug. ’12)

Traces of efforts on SF Management in Korea

Introduction of Policy on HLW management in Korea, KORAD, 7, 2016

7/22

Jul. 2015~Apr. 2016 : TFT for national plan for HLW management

• Consisting of 50 people(including experts of academic field, related organizations, and

government agencies and lawyer) have in-depth review of the draft national plan

• AEC decided the National plan for HLW management in Jul. 25, 2016.

5

Oct. 2013~Jun. 2015 : Public Engagement Commission on SNF(PECOS)

• Collected opinions of the public, local residents of NPP areas and stakeholders by

means of various tools such as town hall meeting, deliberative poll, etc. (about 370,000

people participated)

• Submitted the recommendation report to the government (Jun. 2015)

4

Deliberative Poll Discussion at the National Assembly Town hall meeting

Traces of efforts on SF Management in Korea

Introduction of Policy on HLW management in Korea, KORAD, 7, 2016

8/22

• Siting URL(2020)→Start of RD&D on SNF disposal(2030)→Operation of final repository(2051)

• Constructing predisposal storage within URL site, but on-site short-term storage also considered if necessary

• Setting up ‘Environment Monitoring Center(tentative)’ in the siting region of URL & repository, to which the related costs will be paid

• In case of constructing on-site short-term storage, the storage fee will be paid to the regions and the ‘Foundation of local residents(tentative)’ will be organized

• Legislating & amending the related laws, and preparing for the phased plan for R&D and regulatory system

• Establishing the organization for R&D and management of SNF

• Organizing the ‘Minister’s Meeting(tentative)’ & ‘Task group for SNF management(tentative)

2020 2030 2040 2051

Foundation of local residents Storage fee to be paid

Environment Monitoring Center Costs to be paid

Site selected

Starting RD&D Construction of final repository

PECOS’s Recommendations

9/22

III. National Policy of HLW Management

10/22

National Policy of HLW Management(2016.07)

KINS-NRC Technical Meeting, 11, 2017

11/22

National Policy of HLW Management

1. Site / Storage Type

2. Master Plan

3. Business Contract

4. Licensing Prep.

Licensing Review

Construction/Manufactur

-ing

Operation (~’35)

(April, 2018) Applying CPOL*

(Dec., 2019)

Completion (Dec., 2024)

Construction permission

Hanbit (Younggwang) Kori

* Change Permit of Operating License

KHNP-Spent Fuel Dry Storage Facility Project Plan (Preliminary)

KINS-NRC Technical Meeting, 11, 2017

12/22

IV. Overview of research and development for storage

13/22

KORAD 21 (Dual purpose cask) and KORAD21C (Concrete storage cask)

DPC and Concrete Cask under Development

Neutron

absorber cover

Lid bolt Lid

Trunnion

Thermal

fin

Neutron

absorber

Canister

Impact

limiter

Trunnion

Cask lid

Canister lid

Trunnion

Heat transfer fin

Cask shell

Neutron shield

Disk

Cask body Basket assemblies

Lid bolt

Support rod

Cask lid

Air outlet

Cask body

Air inlet

Disk

Outer shell

Canister

Inner shell

(SUS)

Reinforced

concrete

14/22

DPC and Concrete Cask under Development

Items Description

Capacity - 21 PWR F/A(WH & CE)

Design Basis

Spent fuel

- BU : 45,000 MWD/MTU

- Enrichment : 4.5wt.% U235

- Cooling time : 10 yrs

- Decay heat : 16.8 kw/ canister

Dimensions

- Canister: 1,686 mm O.D. X 4,880 mm L

- Metal cask: 2,216 mm O.D. X 5,285 mm L

- Concrete cask: 3,266 mm O.D. X 6,030 mm L

Weight

- Canister: 33.0t (with loaded fuel)

- Metal cask: 104.7t (with loaded canister)

- Concrete cask: 143.8t (with loaded canister)

Systems descriptions of KORAD 21 and KORAD21C

KORAD21

KORAD21C

15/22

- Scale

Theory

- Heat

Removal

Test

Structural Thermal Aging (Degradation)

TR – Regulatory requirement

ST –Structural Analysis Verification

ST – Thermal Analysis Verification

ST – Thermal Analysis Input Data

ST – Concrete Freeze-Thaw

ST – Canister SCC

ST – O-Ring Test

- 9 m Drop

- 1 m Puncture

- 800 ℃ Fire

- 200 m

Immersion

- Aircraft crash

Test

- Tip-over Test

- Seismic Test

- Horizontal

Mode

- Vertical

Mode

- Property

Test

- Freeze-

Thaw of

Ring

Structure

- Stainless

Steel SCC in

salty

Environ.

- SCC

Mechanism

- O-Ring

leakage

- Leakage-

salty air

* SCC: Stress

Corrosion

Cracking

KAERI’s Performance Evaluation Tests & Analyses

16/22

Test model and measurements

Full scale model

98 thermocouples (80 on cask, 18 ambient)

Flow rate measurements

Heat load : 16.8 kW simulated with heater (no

internal structure)

Test conditions

Normal condition

Off-normal condition (half blockage of air inlets)

Accident condition (full blockage of air inlets)

Sensitivity analysis for bird-screen mesh size

0°

90° 180°

KORAD21C heat removal test facility

Half-blockage types

Heat Removal Performance Test

Mesh Wire dia.

(mm) Opening

(mm) Open area

(%)

4 0.71 5.64 78.9

6 0.71 3.53 69.6

8 0.71 2.46 60.2

10 0.71 1.83 51.8

Bird-screen mesh types

17/22

▲Temp. measure

▲ Test model with measurement systems

Thermo- couples

T/C Scanner

Signal Conditioning & Amplifier

A/D Board

P/C

Scanner (Pitot tube, DPS)

Data Logger

▲ Flow velocity

▲ pressure measure

Test for Effective Thermal Conductivity

Purpose

To find out the detailed temp. distribution

Comparison with analysis results

To develop the valid porous model for analysis

Single canister test model

Test model: Dummy fuel (16x16), Basket, canister

Orientation: Horizontal, Vertical

Heat capacity: 400, 800, 1200W

17 thermocouples x 4 sections

18/22

Impact resistance performance evaluation for KORAD21

and KORAD21C over-pack

Confinement performance evaluation test for DPC under Aircraft

engine crash

Concrete over-pack failure evaluation scheme for high aviation

object impact

Basic research for evaluation of BDB accident (aircraft crash)

Extracted concrete over-pack model under the civil aircraft crash

Collaboration with ADD (Agency of Defense Development)

Test and analysis results for KORAD21C over-pack Test and Analysis results for another over-pack

Impact test for DPC

Aircraft Impact Test and Analysis

19/22

Research Purpose

Verification of sealing performance of metal seal during expected storage period

Accelerated Test

Metal seal: Helicoflex HND 229

Seal test configuration: flanges, heating chamber, leak detector

Accelerated condition based on Larson Miller parameter (LMP)

Metal Seal Accelerated Test

Metal seal

Section

He inlet

He outlet

tCTLMP 10log T : Temp. (K), t : Time (hours)

Chamber

Specimens Equivalent Condition (C=16)

Temperature Time

Real Condition 128 ℃ 50 years

1st 180 ℃ 9 weeks

2nd 160 ℃ 39 weeks

▲ Flange assembly ▲ Heating chamber ▲ Test configuration

20/22

Critical leak rate

Critical leak rate

Design life

1st accelerated test

At the temperature of 180 ℃

Leak rate had been in allowable range.

Target life of metal seal was verified

Keep testing for additional 4 weeks

2nd accelerated test

At the temperature of 165 ℃

Leak rate has been in allowable range.

Target life of metal seal was verified.

Plan to keep testing for a while

Metal Seal Accelerated Test

21/22

Sylvia J. Saltzstein, “Courtesy of Surrogate Spent Nuclear Fuel International Multi-Modal Transportation Test”, Aug. 24, 2017.

Cradle

Plate form (Deck)

Analysis for Vibration & Shock Condition

MMTT(Multi-modal Transport Test)

22/22

The national plan for HLW management was decided in Jul. 2016.

Site selection by 2028

Interim storage operation from 2035

Final repository operation from 2053

KAERI has been performing various evaluations for the storage and

transportation conditions through safety evaluation tests and

numerical simulations.

KORAD21, DPC was verified to maintain its structural integrity

under HAC.

KORAD21C, concrete storage system was demonstrated to

comply with requirements successfully.

Transportability assessment after storage has been conducted based

on data from DOE-ENSA MMTT(Multi-modal Transportation Test).

Test will be planned for Korean sea transport condition.

Summary

23/22

Thank You for Your Attention