"Update on the Intrinsic Proliferation Resistance and Physical Protection Features of CAREM-25 Reactor"

Transcription

1 "Update on the Intrinsic Proliferation Resistance and Physical Protection Features of CAREM-25 Reactor" D. F. Delmastro and L. Garrigo CNEA, Argentina Technical Meeting on Options to Incorporate Intrinsic Proliferation Resistance Features to Nuclear Power Plants with Innovative SMRs, August 2011, Vienna, Austria.

2 CAREM CAREM is a CNEA (Comisión Nacional de Energía Atómica) project. This project consists on the development, design and construction of a small nuclear power plant. First, a prototype of an electrical output of about 27 MW, CAREM 25, will be constructed in order to validate the innovation of CAREM concept and then developed to commercial version.

3 CAREM National Law 26566/2009 On 17th December 2009, the law declares of national interest, inter alia, the design, construction and start up of CAREM prototype, establishing a special regime. CNEA was entrusted to complete these tasks. After several years of development the CAREM Project reached such a maturity level that the Argentine government decided the construction of CAREM prototype. Several activities are ongoing with the purpose of obtaining the Construction License.

4 CAREM -25 Distinctive Features Integrated primary cooling system Primary cooling by natural circulation Self-pressurized Safety systems relying on passive features

5 Residual Safety First Second Pressure Supression Containment Injection Heat Shutdown Relief Removal Pool System System Redundancy Independence Physical separation Diversification Fail safe Long grace period Containment and safety systems

6 Residual Heat Removal System The Residual Heat Removal System (RHRS) has been designed to reduce the pressure on the primary system and to remove the decay heat in case of Loss of Heat Sink. It is a simple and reliable system that operates condensing steam from the primary system in emergency condensers. The emergency condensers are heat exchangers consisting of an arrangement of parallel horizontal U tubes between two common headers. The top header is connected to the reactor vessel steam dome, while the lower header is connected to the reactor vessel at a position below the reactor water level. The condensers are located in a pool filled with cold water inside the containment building.

7 Residual Heat Removal System The inlet valves in the steam line are always open, while the outlet valves are normally closed, therefore the tube bundles are filled with condensate. When the system is triggered, the outlet valves open automatically. The water drains from the tubes and steam from the primary system enters the tube bundles and condenses on the cold surface of the tubes. The condensate is returned to the reactor vessel forming a natural circulation circuit. In this way, heat is removed from the reactor coolant. During the condensation process the heat is transferred to the water of the pool by a boiling process. This evaporated water is then condensed in the suppression pool of the containment.

8 Proliferation Resistance and INPRO Proliferation Resistance is defined as that characteristic of a nuclear energy system that impedes the diversion or undeclared production of nuclear material, or misuse of technology,... The degree of proliferation resistance results from a combination of, inter alia, technical design features, operational modalities, institutional arrangements and safeguards measures. These can be classified as intrinsic features and extrinsic measures. IAEA-TECDOC-1434, Methodology for the assessment of innovative nuclear reactors and fuel cycles. Report of Phase 1B (first part) of the International Project on Innovative Nuclear Reactors and Fuel Cycles (INPRO)

9 Proliferation Resistance and INPRO Intrinsic proliferation resistance features are those features that result from the technical design of nuclear energy systems, including those that facilitate the implementation of extrinsic measures. Extrinsic proliferation resistance measures are those measures that result from States decisions and undertakings related to nuclear energy systems. IAEA-TECDOC-1434, Methodology for the assessment of innovative nuclear reactors and fuel cycles. Report of Phase 1B (first part) of the International Project on Innovative Nuclear Reactors and Fuel Cycles (INPRO)

10 Proliferation Resistance and INPRO UR2.2: The combination of intrinsic features and extrinsic measures, compatible with other design considerations, should be optimized (in the design/engineering phase) to provide costefficient proliferation resistance. UR2.2 recognizes that there are cost trade-offs between intrinsic features and extrinsic measures, and encourages their optimization for cost effectiveness. The UR further recognizes that the features and measures must be compatible with other design considerations such as safety and economics, and that the verification costs must be reasonable. IAEA-TECDOC-1434, Methodology for the assessment of innovative nuclear reactors and fuel cycles. Report of Phase 1B (first part) of the International Project on Innovative Nuclear Reactors and Fuel Cycles (INPRO)

11 CAREM and safeguard implementation CAREM NPP has 4 main handling and storage fuel areas: - Fuel reception area - Fresh Fuel Storage Room - Reactor Pressure Vessel - Spent Fuel Storage Pool An important feature is that there is only one entrance-exit point.

12 CAREM and safeguard implementation SF Pool Reactor

13 CAREM and safeguard implementation To increase proliferation resistance all the refueling tasks will be developed in the reactor hall, which is designed to allow remote monitoring of all nuclear material handling. The entrance-exit and the interfaces have been designed to allow items accountability / surveillance during they movement / transfer. There is only one spent fuel exit point for controlling and monitoring, so surveillance in extremely facilitated.

14 CAREM and safeguard implementation All the irradiated fissile material is located here Hall integrity checked by remote system No Physical Way to get Access to unauthorized persons Strongly reduce Spent Fuel Control Strongly reduce Reactor I/O Control

15 CAREM core life length Fuel Rod Fuel Assembly

16 CAREM core life length The core life length could be optimized selecting for instance a common variable that should be applied to all the steps of the fuel cycle. Safeguards related costs could be also included. The use of a discount rate is necessary as different steps occur at different times. The influence of the use of different enrichment on CAREM prototype, CAREM-25, was analysed. An important result is that safeguard costs are very small compared against fuel costs and they do not significantly impact on the optimum enrichment (below 5%).

17 PHYSICAL PROTECTION SYSTEM CAREM 25 (PPSC)

18 OBJECTIVES FOR PPSC PREVENT, DETECT, AVOID, DELAY and RESPOND TO MALICIOUS ACTS AFFECTING CAREM-25, PARTICULARLY THOSE AIMING TO: Sustraction and/or disperson of nuclear material. Sabotage or intrusion to power plant, that may generate an accident with severe radiological consequences. Provide the necessary means to avoid that nuclear material, equipment and/or installations are subject to unauthorized use, as established by the Nuclear Regulatory Authority. Monitor and control personnel movements, in order to avoid thefts and vandalic acts. Prevent the unatuthorized use or transmission of technologically-relevant information.

19 RELEVANT DOCUMENTATION A.R.N. AR Norma de protección física de materiales e instalaciones nucleares (Physical protection of nuclear materials and installations) AR Garantías de no desviación de materiales nucleares y de materiales, instalaciones y equipos de interés nuclear. OIEA IAEA-TECDOC-1276 Handbook on the physical protection of nuclear materials and facilities (Año 2002) INFCIRC/225/Rev.4 The Physical Protection of Nuclear Material and Nuclear Facilities (Año 1999) IAEA-TECDOC-967 (Rev.1) Guidance and considerations for the implementation of INFCIRC/225/Rev.4,The Physical Protection of Nuclear Material and Nuclear Facilities (Año 2000) IAEA Nuclear Security Series No. 4 Engineering Safety Aspects of the Protection of Nuclear Power Plants against Sabotage (Año 2007) IAEA Nuclear Security Series No. 8 Preventive and Protective Measures against Insider Threats (Año 2008) Others Nuclear Safety Convention (1994) OIEA INFCIRC/449

20 DEVELOPMENT OF PPSC According to the recommended practice by IAEA:

21 THREAT ANALYSIS Credible threats 1. External attack 2. Airplane impact 3. Explosives detonation in the plant (suicidal attack or not). 4. Car-bomb attack (suicidal or not). 5. Explosives detonation outside the perimeter of the installation. 6. Sabotage to systems, structures and components without using explosives. 7. Theft of nuclear material 8. Attack to the Physical Protection System (in order to facilitate intrusion). 9. Attack to the Physical Protection Control Center 10. Demonstrations against the power plant 11. Submittal of explosive letters or packages 12. Occupation and control of the installation for a short period of time

22 CONSEQUENCES ANALYSIS Reactor core CONSEQUENCES SOURCE ACT CONSEQUENCE Irradiated Fuel Elements Unirradiated fuel elements Sabotage to systems that assure safe shutdown Theft Sabotage to refrigeration and shielding systems Theft Release to containment, and possibly to the environment, of large queantitires of radioactive material. Nuclear explosives preparation Radiation exposure of plant personnel Nuclear explosives preparation

23 AREA LIMITS DEFINITION --- Protected Area --- Controlled Area

24 SATELLITE VIEW

25 AREA LIMITS DEFINITION Area with FE Vital Area I

26 DESIGN CRITERIA OBJECTIVE OF PPCS BACKGROUND CAPACITY OF PPCS SYSTEMS OUTSIDE MONITORING PERIMETER PROTECTION ACCESS CONTROL MONITORING AND CONTROL COMMAND

27 DESIGN CRITERIA PHASES SYSTEM Site preparation Civil Outside Protection Visual control Visual control, systematic. PHASES Construction Electromechanical Early warning by means of optical and electronic equipment Start-up Early warning by means of optical and electronic equipment Perimeter protection Establish perimeter limits. Avoid or delay intrusions Idem + perimeter fence completed Idem + Detect intrusions. Reactor fence completed Idem. Fully functional. Access Control Control: *Personnel In/Out *Idem *Interact with Perimeter Protection System and Control and Monitoring System *Idem + Reactor Perimeter control Control: In/Out Protection: Detect, avoid and delay unauthorized entries.

28 DESIGN CRITERIA PHASES FUNCTIONS SYSTEM Monitoring and Control (functions do not change, but areas of interest do) Site preparation *Establish authorized areas and scheduled hours. *Detect intrusions and anomalies. *Detect unatuthorized use of CAREM materials and equiment. PHASES Building and Construction Civil Electromechanical Start-up Idem Idem Idem Fully functional Command *Collect and process information realtive to PPSC systems. *Establish reliable communication channels *Provide immediate response Idem Idem Idem Fully functional

29 OUTSIDE MONITORING The Outside Monitoring System acts in order to detect and inform of activities that may constitute a threat to the installation. Structure Outside lighting Clear visibility from the inside Optical and electronic detection systems. Surveillance and oversight

30 PERIMETER PROTECTION SYSTEM Its definition has been coordinated with NA-SA. STRUCTURE Two perimeters Outer perimeter: Encompasses the whole Lima-Carem Site and consists of a fence and detection equipment. Inner perimeter: Encompasses the reactor building and consists of a double fence and detection equipment.

31 PERIMETER PROTECTION SYSTEM FENCE OUTER PROTECTION PERIMETER Microphonic detectors Surveillance and inspections Cleared zone

32 PERIMETER PROTECTION SYSTEM Double Fence INNER PROTECTION PERIMETER Microphonic detectors Microwave sensors Surveillance Lighting

33 ACCESS CONTROL SYSTEM IN-DEPTH PROTECTION Access control to vital and sensitive areas Zona Controlada Vital or Sensitive Area Protected Area Access control to protected area Access control to controlled area

34 ACCESS CONTROL SYSTEM CONTROLLED AREA ACCESS CONTROL

35 ACCESS CONTROL SYSTEM ACCESS TO PROTECTED AREA 1- Metal detector gate 2- X-ray Scanner 3- Turnstiles 4- Radiation detector 5- Security Camera 6- Checkpoint Surface partially covered

36 ACCESS CONTROL SYSTEM Vehicle access to Protected Area Vehicular access

37 MONITORING AND CONTROL SYSTEM Acts on: Controlled Area Perimeter Zones of Controlled Area close to Protected Area Protected Area Perimeter Open Spaces Inside Buildings EQUIPMENT: CCTV Areas being monitored

38 COMMAND SYSTEM Gendarmeria Nacional Director Response Force Administrative Support Operations Maintenance Alarms Central Station Organic relationship Functional Relationship Gates Coordination

39 Feedback from Fukushima Accident CAREM-25 considers in it design base the loss of heat sink and black-out during the grace period. Provisions are considered to allow after the grace period core decay heat removal using the fire extinguish system or an autonomous system. Provisions are considered to allow after the grace period containment cooling using the fire extinguish system or an autonomous system.

40 Feedback from Fukushima Accident Provisions are considered to allow after the grace period electrical supply to safety related systems using autonomous generation systems. Seismic requirements were reviewed. Provisions are considered to cover the spent fuel pool. These provisions could improve Safety, Intrinsic Proliferation Resistance and Physical Protection.

41 Conclusions Evaluating proliferation resistance different costs should be considered. Intrinsic proliferation resistance features that facilitate the implementation of extrinsic measures are considered in CAREM design. Argentina has a wide experience in the surveillance and control of nuclear material.

42 Conclusions CAREM-25 considers in it design base the loss of heat sink and black-out during the grace period. Provisions are considered to protect spent fuels and to facilitate after the grace period core decay heat removal. These provisions could improve Safety, Intrinsic Proliferation Resistance and Physical Protection.

43 Thank You