An interview with Vitaly Petrunin, First Deputy General Director, First Deputy General Designer at JSC “Afrikantov OKBM”
- I guess we should start with the RITM-200 project after all. How was the cycle of development and delivery of the RITM-200 reactor plant to the icebreakers of Project 22220? What was the most difficult thing? What original solutions were used?
- I will start with the fact that the RITM-200 reactor plant is a fundamentally new plant that differs significantly from the previous generations of ship reactors. It is of integral type, that is, the main equipment is placed directly inside the steam generating unit vessel. Due to such a solution it is 1.7 times lighter, two times more compact, and almost 20% more powerful than the currently used KLT reactor plants for the icebreaker fleet. This allowed us to make new icebreakers dual-draft and ensure the enhanced performance data of the vessel in terms of speed, icebreaking capability, and other parameters. Of course, we took into account the experience in building and operating reactor plants for the Russian icebreaker fleet: from OK-150, the first one on the icebreaker Lenin, to KLT-40S installed on the FNCP Akademik Lomonosov. Their total operating experience is more than 400 reactor-years.
RITM-200 is the first marine reactor plant fully manufactured within the outline of the Mechanical Engineering Division of Rosatom – Atomenergomash Company (JSC “Afrikantov OKBM” is the Chief Designer and Complete Supplier). The manufacturer of vessel equipment was ZiO-Podolsk that mastered this type of equipment from scratch. Naturally, the process of mastering faced certain difficulties. Some solutions had to be developed right on the go. Specifically, several new technologies and tools were introduced at once. Among them is a new technology of ultra-precise deep hole drilling, new types of cutting tools, and many others.
- How was the gained experience taken into account when developing the RITM-400 reactor plant? What characteristics will it have?
- The RITM-400 reactor plant is an evolutionary development of RITM-200 with unit power increased up to 315 MW, which outperforms all existing shipboard reactor plants. In the process of manufacturing the reactor plant, the already mastered element base and engineering solutions will be used. Currently the technical design of the plant has been developed. RITM-400 is 1.8 times more powerful than RITM-200, which allows the nuclear icebreaker Leader to have higher performance characteristics. Specifically, it will be capable of breaking the ice of 4.3 m in thickness and clearing channels of up to 50 m in width. This will result in year-round navigation on the Northern Sea Route (NSR), including large-capacity vessels.
- Will the size and layout of RITM-400 change?
- The main difference, as I have already said, is heat power increased by 1.8 times. The layout and circuit solutions will be similar in many respects to those of RITM-200 for the vessels under Project 22220, with the maximum unified element base and reactor plant equipment. Thus, we are getting a power range for the icebreakers of different designs, which is essential for the further development of the nuclear fleet.
- Reactor plants are always subject to higher safety requirements. What measures will be taken to eliminate emergencies with the new plant?
- You are right, the condition for the project implementation is compliance with the rules and application of all necessary systems to ensure active and passive safety. Already implemented projects ensure compliance with all IAEA requirements for use of atomic energy. The principle of defense in depth, including various protective barriers designed to prevent an accident or minimize the consequences, if any, is used. Safety systems include all the technical facilities currently available. The plant design also excludes the mutual influence of safety systems that prevents them from performing their functions properly. This is achieved, among other things, by means such as physical separation and functional independence.
- Will RITM reactor plants be used on other vessels or on land?
- Last year we completed the development of a conceptual design for a land-based twin-unit NPP with RITM-200 reactors. We took a serial ship reactor for new icebreakers and "inscribed" it into the land-based plant. The design has been approved by the Scientific and Technical Board of Rosatom and will become the basis for the development of projects aimed to build specific nuclear power plants in Russia. You know, I have been working on small reactors for a long time and I am glad that I have lived up to the day when the projects are getting implemented on a large scale. Over the past few decades, there have been many attempts, talks, and decisions. But, apart from the reactor for the FNCP, nothing has been implemented. The RITM-200 project was lucky though. Even in the Soviet times, a project was rarely implemented so quickly. In 2009, I defended the RITM-200 project at the Scientific and Technical Board of Rosatom, and in 2019, these reactors are being serially manufactured for FSUE “Atomflot.” Six reactors have already been manufactured and delivered for three icebreakers, and the first icebreaker of Project 22220 is expected to be commissioned in 2020.
- What modifications of this line are expected in the near future?
- Today the RITM-200B project has already been developed for a small-sized single-reactor offshore icebreaker intended for operation in shelf seas. On the basis of RITM-200 we have also developed a RITM-200M reactor plant for an optimized floating power unit (OFPU). Currently, a preliminary design of the OFPU and self-propelled electricity supply ship (ESS) with two RITM-200M reactor plants is being developed.
Furthermore, the prospects for use of RITM reactors are quite broad and are not limited only to the icebreaker fleet