Scaled-Down Simulation of BN-350 Sodium Coolant Processing Facility
Design and Development of a Scaled-Down Simulation Complex of Automated Control and Dataware System for BN-350 Sodium Coolant Processing Workflow
Tech Area / Field
- FIR-DEC/Decommissioning/Fission Reactors
8 Project completed
Senior Project Manager
Zalouzhny A A
Nuclear Technology Safety Center, Kazakstan, Almaty
- National Nuclear Center of the Republic of Kazakstan, Kazakstan, Kurchatov\nMAEC-Kazatomprom, Kazakstan, Aktau
- Argonne National Laboratory (ANL) / West, USA, ID, Idaho Falls\nRWE NUKEM limited, UK, Dors, Winfrith Newburgh
Project summaryIntroduction and Overview.
The nuclear power engineering development as one of the most promising branches of heat and electric power generation is directly related to solving a set of tasks aimed at enhancement of efficiency and safety of nuclear power facilities and nuclear waste recycling, reprocessing and disposal. Recently, nuclear waste recycling, reprocessing and disposal has become highly acute as the number of nuclear power facilities steadily goes up and nuclear facilities commissioned in the past require either reconstruction and improvement or decommissioning followed by conservation.
Considering specific physical-chemical features of sodium and nature of using it as a coolant, the processing procedure consists of a number of major stages:
1. Decontamination of the first loop sodium coolant, i.e. removal of the most active and long-lived fission products, particularly, cesium-137.
2. Sodium discharge from the first and second loops into special tanks for long-term storage.
3. Low-active sodium reprocessing into a neutral substance (chemically inactive) suitable for safe long-term storage or disposal.
4. Safe long-term storage of sodium processing products for 50 years and more, means to control and monitor the state of the substance stored being provided.
The most labor-intensive and hazardous process with regard to the sodium coolant processing is its transfer into a chemically neutral substance which can later be stored in appropriate places specially equipped for these purposes.
An important stage of the sodium processing is technology testing. This implies solving of tasks related to development of optimal algorithms of the workflow management, its dataware, analysis of emergency situations, personnel training in techniques of safe sodium processing facility operation, etc. At present, this task package may be solved applying up-to-date design techniques, including computer modeling (simulation).
Nuclear Technology Safety Center (NTSC) coordinates activities on development of a liquid-metal coolant processing facility at BN-350 carried out under the US assistance programs for BN-350 decommissioning.
Expected Results and Their Application.
The research under the present project falls under the technology area of fission reactors decommissioning (FIR-DEC).
The activities under the present project are mainly aimed at development of workflow control (adjustment) and dataware (measurement and control of workflow parameters) systems for the liquid-metal sodium processing facility and at advancement of sodium processing technology, study of emergency situations possible during operation of the processing facility operation and training the operating personnel.
Computer-based modeling methods provide a basis for solving these tasks. They are capable to create workflow model complexes of any complexity with partial or full utilization of real equipment that takes measurements, fulfills control functions, and processes and presents information. This approach is quite effective for solving tasks related to workflow mastering and advancement, synthesis of control algorithms, information processing and presentation.
As a result of this project, an approved technical design is expected for development of control and data systems of the sodium processing facility in full scope. The design will comply with all regulating documentation currently in force in the Republic of Kazakhstan. An operating sample of a simulation complex of the sodium processing facility is also expected to result from this project. The knowledge and experience of solving these tasks can be used in practice in many scientific, technical and economical areas of the Republic of Kazakhstan.
Meeting ISTC Goals and Objectives.
This project has the following as its objects: reorientation of scientists and engineers formerly engaged in nuclear weapon developments, particularly in design and operation of weapon-grade breeding facilities or in researches of nuclear weapon components and elements to an area of activities related to their knowledge and expertise application to solve tasks in peaceful Kazakhstan economy. This area includes the tasks directly related to nuclear power plants safety development, design and implementation of decommissioning and reconstruction projects and programs for served-out reactors, particularly, BN-350.
New knowledge and expertise gained in the course of this project implementation will be useful in the world engineering practice to solve tasks related to nuclear power engineering.
Scope of Activities.
Design and development of a scaled-down simulation complex of automated control and dataware system for BN-350 sodium coolant processing workflow will allow solving a package of technical issues related to processing technology, synthesis of control algorithms, information processing and granting, workflow management operational schemes testing, emergency analysis, and operating personnel training. The order of the project implementation is presented in tasks below.
Task 1 – Structural and Functioning Design of a Scaled-Down Simulation Complex.
Under this task, technical requirements to the sodium coolant processing facility are formulated and specified. All the available information relevant to the task of management and dataware systems designing for sodium processing facility taking into account similar experience obtained by other institutions previously.
Structural and functional schemes of the simulation complex and designed. Sodium processing technology is analyzed and revised, mathematical formulation of the control algorithm and workflow description is developed.
Task 2 – Software and Algorithm Design.
Under this task, the following issues are addressed: selection and justification of hardware and software required to realize mathematical models of the simulator reflecting the sodium process workflow functioning. Applied software of the simulator is being developed. Impedance matchers are developed for the process workflow mathematical model with real equipment applied to realize the sodium process workflow control and dataware tasks. Control algorithms are developed for the workflow and technological data processing and granting.
Task 3 – Realization of a Scaled-Down Simulation Complex.
This task implies full realization of the scaled-down simulation complex of automated control and dataware system for BN-350 sodium coolant processing workflow, adjustment, setup and testing.
Task 4 – Adjustment and Model Research and Tests of a Scaled-Down Simulation Complex.
This task is the final stage of a scaled-down simulation complex realization and implies the following work: complex model study of the scaled-down simulation complex; testing of dataware control algorithms; specification and correction of sodium processing technology, if necessary; studying emergency situations related to the sodium processing workflow; workflow operational schemes testing; and operating personnel training.
Task 5 – Contract Administration.
This task implies activities related to coordination of the project work between the performers, project work arrangement, technical and administrative control and deliverables analysis, deliverables translation into English, execution of and payment for materials and equipment required for the project implementation, organization and hold of science and technology workshops under the project, financial administration and project-related financial-accounting records keeping. Implementation of this task is fully laid upon the Nuclear Technology Safety Center.
Role of Foreign Collaborators/Partners.
For a long time, the US and Argonne National Laboratories (ANL) in particular, take an important part in implementation of different-nature projects related to BN-350 reactor decommissioning. Since ANL is widely experienced in the fast (breeder) sodium-cooled reactors designing, construction, operation, deactivation and decommissioning, the ANL leading role in the implementation of projects related to BN-350 reactor decommissioning is invaluable.
When Kazakhstan declared its intention to decommission BN-350 reactor and put it into a safe storage state, an inquiry was made for provision of US/ANL support to Kazakhstan. ANL and other experts in the area of sodium-cooled reactors are eager to share their knowledge and expertise with Kazakhstan specialists in the field of fast (breeder) reactors decommissioning on the basis of implementation of appropriate programs, projects and R&D seminars.
Technical Approach and Methodology.
Classical and up-to-date design methods are employed for the control system synthesis, i.e. selection of an optimal algorithm to control the process parameters. These methods are used for both linear and non-linear control objects. Usually, these methods have a control object concept as a basis. In our case, the control object is the workflow of the liquid-metal sodium processing. When designing a control system, an essential task is to describe the control object in detail. For this purpose, methods for identification, modeling and simulation of the dynamic object or the workflow are applied, based on the mathematical formulation or presentation of the control object.
The information theory used to identify the sampling frequency of the measurement information and methods for its processing and presentation is applied to design and develop a data acquisition system that will gather, process and present the workflow information.
The International Science and Technology Center (ISTC) is an intergovernmental organization connecting scientists from Kazakhstan, Armenia, Tajikistan, Kyrgyzstan, and Georgia with their peers and research organizations in the EU, Japan, Republic of Korea, Norway and the United States.
ISTC facilitates international science projects and assists the global scientific and business community to source and engage with CIS and Georgian institutes that develop or possess an excellence of scientific know-how.