KR9600298KAERI/AR-436/96

The Status of Improved PressurizedHeavy Water Reactor Development

- A New Option for PHWR -

VOJ, '•? 0 5

7 ^

1996V1

H 900

CANDU ^ " ^ 4 i ^ ^If- ^ 7l7lt- 7l^-

V^ 4807}]

(Darlington

Bruce BW1 «l«fl

Summary

Currently, the 900 MWe class Improved Pressurized Heavy Water Reactor (PHWR),

which is a type of CANDU reactor based on the systems and components of

operating CANDU plants, is under development. The improved PHWR has a 480 fuel

channel calandria, uses 37 element natural uranium fuel bundles and has a single unit

containment Adaptation of a steel-lined containment structure and improved

containment isolation systems permit a reduced exclusion area boundary (EAB)

compared to the existing larger capacity CANDU reactors (Darlington, Bruce B).

The Improved PHWR buildings are arranged to achieve minimum spacing between

reactor units. Plant safety and economy are increased through various design changes

based on the operating experience of existing CANDU plants.

CONTENTS

Summary

Contents

1. Introduction

2. Design Basis

3. Design Improvements

3.1 Plant Layout

3.2 Reactor Building

3.3 Reactor System

3.4 Heat Transport System

3.5 Shutdown Cooling System

3.6 Moderator System

3.7 Safefy System

3.8 Control and Instrumentation System

3.9 Other Systems

4. Operation and Maintenance

4.1 Capacity Factor

4.2 Operation and Maintenance Cost Reduction

4.3 Reliability Improvements

4.4 Plant Life Time Extension

5. Conclusion

References

2.

3.

Summary

Contents

3.1

3.2

3.3

3.4

3.5

3.6

3.7

3.8

3.9

4. £ 3 5J

5.

4.1

4.2

4.3

4.4

1.

, S.

3. 1.

1995. 12. 31

Pickering 1Pickering 2Pickering 3Pickering 4Bruce 1Bruce 2Bruce 3Bruce 4Point LepreauGentiUy-2Wolsong 1EmbalsePickering 5Pickering 6Pickering 7Pickering 8Bruce 5Bruce 6Bruce 7Bruce 8Darlington 1Darlington 2Darlington 3Darlington 4Cernavoda 1-5Wolsong 2,3&4

CanadaCanadaCanadaCanadaCanadaCanadaCanadaCanadaCanadaCanadaKorea

ArgentinaCanadaCanadaCanadaCanadaCanadaCanadaCanadaCanadaCanadaCanadaCanadaCanada

RomaniaKorea

-%-ig MWe (net)515515515515848*848*848*848*633638638600516516516516860860860860881881881881

665 x 5668 x 3

197119711972197319771977197819791983198319831984198319841984198619851984198419871990198919911992

1995/19991997/1999

* Electrical equivalent (electricity plus process steam)

- 1 -

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- 11 -

REACTIVITYMECHANISMS

SHIELD TANK OVER 0 E C K

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REACTOR VAULTROOF

VERTICAL REACTIVITYCONTROL UNITS

LIQUID ZONECONTROL TRENCHES

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CANDU 6 ^ ^V^TJl-S- ^ w l m f e S. 5 4

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CANDU 6 4 ^

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CANDU 6 4 i o J

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CANDU 3 4 ^Tfu<H-i-

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Shield Tank/ End Shield

CANDU 6 4 ^

- 23 -

REACTOR BUILOINQ

GAS ISOLATIONVALVES

-, . " : . ISOLATION• m' VALVES

RECOVERY SUMPPUMPS ISOLATION

VALVES

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13.

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3.8

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Unavailability^- ^ ^ . ^ l ^ ^ - c - Computer-based Shutdown System

Large central mimic display

Sit-down Console^^

- 25 -

Station Infoimation System

Main Control Area

Operator Workstation

Main Control Area

Operator Wortcstation

Plant Control System Group 1Safety System

Monitor

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QroupiChannel Test

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Special SafetySystems

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- 26 -

3.9

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5. CANDU

Double-ended Refuelling System^- A]-g-§]-jL ^^)nv 4^.3}. ^-o

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TOP GUIDE

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OUTER SUSPENSION FRAME

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15%

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4.3

(Human Factors Engineering) 7]#^g-

4.4

(Pressure

- 29 -

5.

CANDU

900

DarUngton CANDU

Bruce B

CANDU 3

ifl-¥-°fl Steel-liner!- 0.2% volume per day

700ml-

377fl ^S . ^ - t)-«-g-

CANFLEX

Single Loop Type-i-

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One-way Rupture DiscsS

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CANDU

(EABM-

7fl

- 30 -

1. "Technical Outline, CANDU 9 480/NU", 69-01372-TED-001 (Rev.O), AECL (May

1995)

2. "Improved Pressured Heavy Water Reactors", 69-01371-050-002 (Rev.O),

KAERI/AECL (Dec., 1994)

3. R.S.Hart et al, "CANDU 9 - Overview" Jun. 1993, IAEA Technical Committee

Meeting on Advances in Heavy Water Reactors.

4. R.S.Hart and D.NPadhi, "Emergency Core Cooling System Simplification", Jun.

1993, IAEA Techical Committee Meeting on Advances in Heavy Water Reactors.

- 31 -

1996. 3.

4 i ^ : -^^2,3,4X7)7l^^e)^ | : 3-g- : ^ 1 ^ 7 1 ^ ^ ^ ^ : M]-Efle

if ^ f

^ cL / r

if:-84 ^

J4 Jl ^ -g- »

R.R T.R A.R

O

R.R : Research Report

T.R : Technical Report

A.R : State-of-the-Art Report

BIBLIOGRAPHIC INFORMATION SHEET

Performing Org. ReportNo.

Sponsoring Org.Report No.

Standard Report No.INIS Subject

Code

KAERI/AR-436/96

Title/Subtitle

The Status of the Improved Pressurized Heavy Water Reactors Development/A New Option to PHWR

Project Manager and Dept Tae-Keun PARK Wolsong 2,3,4Tech. Coord. Dept

Researcher and Dept

J. W. Yeo, Project Development Dept.

Pub. place Taejon Pub. Org KAERI Pub. Date 1996. 3.

Page P. Ill and Tab Yes ( o ) No ( ) Size cm

Note

Classified Open ( o ), Class Report Type State-of-the-Art-Report

Sponsoring Org. Contract No.

Abstract (About 300 words)

Currently, the 900 MWe class Improved Pressurized Heavy Water Reactor

(PHWR), which is a type of CANDU reactor based on the systems and

components of operating CANDU plants, is under development The improved

PHWR has a 480 fuel channel calandria, uses 37 element natural uranium fuel

bundles and has a single unit containment Adaptation of a steel-lined

containment structure and improved containment isolation systems permit a

reduced exclusion area boundary (EAB) compared to the existing larger capacity

CANDU reactors (Darlington, Bruce B). The Improved PHWR buildings are

arranged to achieve minimum spacing between reactor units. Plant safety and

economy are increased through various design changes based on the operating

experience of existing CANDU plants.

Subject Keywords (About 10 words)

Improved PHWR, Large CANDU, CANDU 9, Development of Improved PHWR

INIS

KAERI/AR-436/96

(TR, AR-g-2,3,4^71

( o ),-?-( ) 3.7]

1996. 3.

cm

CANDU

900 MWef CANDU

: 4807fl

>Q:#± (Darlington 31 Bruce BW «1«J (EAB)*

, CANDU 9,