International Research Institute for Nuclear Decommissioning

Presentation on theme: "International Research Institute for Nuclear Decommissioning"— Presentation transcript:

1 International Research Institute for Nuclear Decommissioning
Request for Proposal (RFP) for Conceptual Study of Innovative Approach for Fuel Debris Retrieval and Feasibility Study of Essential Technology International Research Institute for Nuclear Decommissioning

2 Purpose of this Project
Submersion Method RPV ＤＳP PCV Barrier Manipulator ・Cut/Store equipment ・Grabbing equipment Container 100t over head crane Method to exploit radiation shielding effect by water SFP → Submersion up to the top of the PCV or to the level required to cover accumulated fuel debris could be difficult given that the PCV was heavily damaged by the accident. Fuel debris Alternative retrieval method (Innovative Approach) without submerging PCV with water is deemed necessary and so stipulated in the Mid-to-Long-Term Roadmap by Japanese Government. Innovative Approach RPV ＤＳP オペフロ PCV Manipulator ・Cut/Store equipment ・Grabbing equipment Container 100t over head crane Barrier Method without submersion → Request for Information (RFI) on the Innovative Approach of Fuel Debris Retrieval and relevant technology that supports the Innovative Approach was performed by METI through the IRID. About 200 pieces of information were received from Japan and overseas countries. SFP Fuel debris In reference to RFI results, this project is aimed at the conceptual study of Innovative Approach to retrieve the fuel debris without submerging PCV with water and the feasibility study of essential technologies to support the Innovative Approach.

3 The concept of Innovative Approach vs submersion method
RPV ＤＳP PCV Barrier Manipulator ・Cut/Store equipment ・Grabbing equipment Container 100t over head crane RPV SFP ＤＳP PCV Barrier Container 100t over head crane Fuel debris Fuel debris Fuel debris is cut and stored under water. Innovative Approach RPV ＤＳP PCV Manipulator ・Cut/Store equipment ・Grabbing equipment Container 100t over head crane Barrier RPV SFP ＤＳP PCV Container 100t over head crane Barrier Fuel debris Fuel debris Fuel debris is cut under water but stored in the air, or cut and stored both in the air.

4 Description of the projects
Project 1: Conceptual Study of Innovative Approach of Fuel Debris Retrieval To conduct conceptual study for the method to retrieve the fuel debris in the air in a safe and stable condition Project 2: Feasibility Study of Visual and Measurement Technology for Innovative Approach To conduct feasibility study of technology to realize practical application of compact and light-weight visual equipment with lighting function, and measurement equipment to characterize the properties of the objects both of which can be used under the very high radiation environment Project 3: Feasibility Study of Fuel Debris Cutting and Dust Collection Technology for Innovative Approach To conduct feasibility study of technology to realize practical application of the equipment capable of cutting the fuel debris (with dust collection function)

5 Structure of this RFP project
Explained at Tokyo workshop in April Internal PCV/RPV investigation Conceptual study of method Fuel debris retrieval　Conceptual study of method Visual　 technology Monitoring technology Cutting technology Transport technology Supporting technology Categorizing RFI Explained in this workshop A-1： Internal PCV/RPV investigation　Conceptual study of method　 Internal PCV/RPV investigation　Conceptual study of method Transport technology Supporting technology Consider the execution on necessity basis Conceptual Study of Innovative Approach for Fuel Debris Retrieval Feasibility Study of Visual and Measurement Technology for Innovative Approach Feasibility Study of Fuel Debris Cutting and Dust Collection Technology for Innovative Approach Scope of this RFP project B-1：Fuel debris retrieval Conceptual study of method A-2： Internal PCV/RPV investigation 　 Required technologies B-2：Fuel debris retrieval　Required technologies Requested by RFI

6 Relationship between overall steps and RFP
Preparation, decontamination, removal of equipment and waste disposal Internal observation 　 Visual and Measurement Technology Safety control (Dose/Boundary/ Criticality etc.) Transfer of cutting or removal internal structure equipment Installation of container and overhead crane, 100- ton class, on the operation floor collecting the fuel debris in a canister and transport Cutting and removal internal structure (dedicated package) removal of used equipment Preparation and confirmation in the plant beforehand Transfer of Fuel Debris Cutting equipment RFP (Method) Installation of new openings and barrier Fuel Debris Cutting and retrieval Fuel Debris Cutting and Dust Collection Technology RFP (Method + Technology) Transfer of internal observation equipment R&D or operation by TEPCO

7 Assumptions and Prerequisites(Unit to study, Scope of study, Time schedule)
C/S and F/S shall be conducted in consideration with following conditions. Unit to study Select the unit to study in proposal. It could be all three units (unit 1 through unit 3) of Fukushima Daiichi NPS, or a specific unit Scope of study In principle, entire interior of PCV including RPV where fuel debris seems to exist. If the scope of the study is aimed at fuel debris retrieval of a specific part of the unit, please write clearly. Scope of the study covers from the start of the initial operation at the unit for fuel debris retrieval (e.g. removal of shield plug) to storing fuel debris in storage canisters and transferring them to the temporary storage. Time schedule (*) Assume that the status check of fuel debris inside the PCV in 2016 to ensure the feasibility in the fuel debris retrieval. Assume that the status check of fuel debris inside the RPV investigation in 2018 to ensure the feasibility in the fuel debris retrieval. Assume that the start of the fuel debris retrieval in 2020. （＊）Period required for licensing application and permit needs not be considered.

8 Assumptions and Prerequisites (On-site operation condition)
PCV/RPV is under high radioactivity and high humidity. Water is dripping inside. Water level inside PCV is the same as current measured or estimated one as of 2014. No radiation shielding effect by water is counted. Assume that air dose rate is 100 Gy/h inside PCV, and 1 kGy/h inside RPV. Give consideration to the possibility of the accumulation of hydrogen gas inside PCV/RPV when cutting fuel debris or internal structures. On-site operation condition Assume that the rubbles are removed and decontamination work proceeds in 2020 when fuel debris retrieval starts. PCV/RPV is under high radioactivity and high humidity. Water is dripping inside. Water level inside PCV is the same as current measured or estimated one as of 2014. No radiation shielding effect by water is counted. Acceptable maximum load for floor of 1.2t/m2 shall be considered. Visibility inside PCV/RPV is very low due to no lighting provided. Inside PCV/RPV are densely installed internal structures. Assume that air dose rate is 100Gy/h inside PCV, and 1kGy/h inside RPV. After the start of the fuel debris retrieval, effective dose rate on the operation floor is 1mSv/h, 3mSv/h in operation area other than operation floor; and 5mSv/h in a passageway inside the building. Use existing opening, hatch, and stairs inside the reactor building for accessing to each floor and delivering the equipment to each floor. No new openings, in principle, shall be created on the outer wall of the building. (Seismic resistance and prevention of leakage of radioactive substance should be considered, if new opening is indispensable.) Dimension of equipment to be brought in, in principle, shall meet with the passageway width of 1.2m and height of 3m. Give consideration to the possibility of the accumulation of hydrogen gas inside PCV/RPV when cutting fuel debris or internal structures. By the start of fuel debris retrieval, 100-ton type overhead crane is installed and available, and spent fuels in SFP and the equipment in DSP are all cleared off. Total weight of equipment installed on the operation floor shall be minimized in consideration of seismic safety. No shielding function or air tight function for boundary is counted to the container covering operation floor. Visibility inside PCV/RPV is very low due to no lighting provided. Inside PCV/RPV are densely installed internal structures. Assume that the rubbles are removed and decontamination work proceeds in 2020 when fuel debris retrieval starts. Acceptable maximum load for floor of 1.2 t/m2 shall be considered. By the start of fuel debris retrieval, 100-ton type overhead crane is installed and available, and spent fuels in SFP and the equipment in DSP are all cleared off. Total weight of equipment installed on the operation floor shall be minimized in consideration of seismic safety. No shielding function or air tight function for boundary is counted to the container covering operation floor. After the start of the fuel debris retrieval, effective dose rate on the operation floor is 1 mSv/h, 3 mSv/h in operation area other than operation floor; and 5 mSv/h in a passageway inside the building. Use existing opening, hatch, and stairs inside the reactor building for accessing to each floor and delivering the equipment to each floor. No new openings, in principle, shall be created on the outer wall of the building. (Seismic resistance and prevention of leakage of radioactive substance should be considered, if new opening is indispensable.) Dimension of equipment to be brought in, in principle, shall meet with the passageway width of 1.2 m and height of 3 m.

9 Assumptions and Prerequisites (On-site operation condition) (1)
PCV/RPV is under high radioactivity and high humidity. Water is dripping inside. Assume that air dose rate is 100 Gy/h inside PCV, and 1 kGy/h inside RPV. Water level inside PCV is the same as of 2014. No radiation shielding effect by water is counted. Give consideration to the possibility of the accumulation of hydrogen gas inside. Unit Unit 1 Unit 2 Unit 3 Water level of accumulated water in PCV Approx. 2.8 m from bottom of PCV (As of Oct 10, 2012) Approx. 0.3 m from bottom of PCV (As of June 6, 2014) Estimated to be approx. 6.5 m from bottom of PCV (As of May, 2014) Unit Unit 1 Unit 2 Unit 3 Humidity in PCV 100% (misty as of Oct, 2012) 100% (water dripping as of July, 2013) Unidentified Hydrogen concentration in PCV as of June 25, 2014 System A： 0.01vol％ System A： 0.05vol％ Dose rate in PCV Approx Sv/h (As of Oct 10, 2012) Approx Sv/h (As of March 27, 2012) Unidentified Dose rate in RPV

10 Assumptions and Prerequisites (On-site operation condition) (2)
現 地 作 業 条 件 作業開始予定の2020年におけるプラントの状況として、瓦礫は撤去され、除染も進められているも のとする PCV、RPV内部は高線量、高湿度。冷却のための注水により水が滴っている PCV内の水位レベルは2014年現在で測定あるいは推定される水位レベルと同等である 水による放射線の遮蔽効果は期待できない 重量物を建屋内に設置または搬入して使用する場合は、床等の耐荷重（1.2t/m2）を考慮する PCV、RPV内部は照明がないため視界不良 PCV、RPVの中には内部構造物が密に配置されている PCV内部の空間線量率は100Gy/hとし、RPV内部の空間線量率は1kGy/hとする PCV外部の実効線量率は、燃料デブリ取出し時はオペフロ：1mSv/h、オペフロ以外の作業エリア： 3mSv/h、建屋内の通路：5mSv/hとする 各階への作業者のアクセス及び遮蔽材や機材の搬入には、原子炉建屋内既設開口やハッチ及び 階段を利用するものとし、原則として建屋外壁に新たな開口を設けない（ただし、新規開口部を必 要とする場合は、耐震性や放射性物質の漏えい防止について配慮すること） 搬入する機材の大きさは、原則として通路の幅1.2m、高さ3mに適合すること PCV及びRPV内部に蓄積される可能性のある水素ガスについて配慮すること 燃料デブリ取出し作業開始時には、オペフロに100トン級の天井クレーンが設置済みで、使用済燃 料プール及び機器貯蔵プール内の使用済み燃料や機器は搬出済み 耐震安全性を考慮し、オペフロ等に新規に設置する機材等の総重量は極力少なくする バウンダリの検討において、オペフロを覆うコンテナには遮蔽機能及び気密機能を期待しない Visibility inside PCV/RPV is very low due to no lighting provided. Inside PCV/RPV are densely installed internal structures. Core shroud Feed water sparger Neutron flux measurement guide pipe Upper grid Core support plate Piping for core spray Jet pump Piping for detection of differential pressure and standby liquid control system Fuel assembly Steam dryer Steam separator Reactor pressure vessel head Control rod drive mechanism Main body of reactor pressure vessel *Photos are taken at Unit 5 (Just for reference)

11 Assumptions and Prerequisites (On-site operation condition) (3)
現 地 作 業 条 件 作業開始予定の2020年におけるプラントの状況として、瓦礫は撤去され、除染も進められているも のとする PCV、RPV内部は高線量、高湿度。冷却のための注水により水が滴っている PCV内の水位レベルは2014年現在で測定あるいは推定される水位レベルと同等である 水による放射線の遮蔽効果は期待できない 重量物を建屋内に設置または搬入して使用する場合は、床等の耐荷重（1.2t/m2）を考慮する PCV、RPV内部は照明がないため視界不良 PCV、RPVの中には内部構造物が密に配置されている PCV内部の空間線量率は100Gy/hとし、RPV内部の空間線量率は1kGy/hとする PCV外部の実効線量率は、燃料デブリ取出し時はオペフロ：1mSv/h、オペフロ以外の作業エリア： 3mSv/h、建屋内の通路：5mSv/hとする 各階への作業者のアクセス及び遮蔽材や機材の搬入には、原子炉建屋内既設開口やハッチ及び 階段を利用するものとし、原則として建屋外壁に新たな開口を設けない（ただし、新規開口部を必 要とする場合は、耐震性や放射性物質の漏えい防止について配慮すること） 搬入する機材の大きさは、原則として通路の幅1.2m、高さ3mに適合すること PCV及びRPV内部に蓄積される可能性のある水素ガスについて配慮すること 燃料デブリ取出し作業開始時には、オペフロに100トン級の天井クレーンが設置済みで、使用済燃 料プール及び機器貯蔵プール内の使用済み燃料や機器は搬出済み 耐震安全性を考慮し、オペフロ等に新規に設置する機材等の総重量は極力少なくする バウンダリの検討において、オペフロを覆うコンテナには遮蔽機能及び気密機能を期待しない Assume that the rubble is removed and decontamination work proceeds in 2020. By the start of fuel debris retrieval, 100-ton class overhead crane is installed and available, and spent fuels in SFP and the equipment in DSP are all cleared off. Acceptable maximum load for floor of 1.2t/m2 shall be considered. Total weight of equipment installed on the operation floor shall be minimized. No shielding function or air tight function for boundary is counted to the container covering operation floor. RPV SFP Torus room ＤＳP Operation floor PCV Container 100t over head crane Barrier

12 Assumptions and Prerequisites (On-site operation condition) (4)
現 地 作 業 条 件 作業開始予定の2020年におけるプラントの状況として、瓦礫は撤去され、除染も進められているも のとする PCV、RPV内部は高線量、高湿度。冷却のための注水により水が滴っている PCV内の水位レベルは2014年現在で測定あるいは推定される水位レベルと同等である 水による放射線の遮蔽効果は期待できない 重量物を建屋内に設置または搬入して使用する場合は、床等の耐荷重（1.2t/m2）を考慮する PCV、RPV内部は照明がないため視界不良 PCV、RPVの中には内部構造物が密に配置されている PCV内部の空間線量率は100Gy/hとし、RPV内部の空間線量率は1kGy/hとする PCV外部の実効線量率は、燃料デブリ取出し時はオペフロ：1mSv/h、オペフロ以外の作業エリア： 3mSv/h、建屋内の通路：5mSv/hとする 各階への作業者のアクセス及び遮蔽材や機材の搬入には、原子炉建屋内既設開口やハッチ及び 階段を利用するものとし、原則として建屋外壁に新たな開口を設けない（ただし、新規開口部を必 要とする場合は、耐震性や放射性物質の漏えい防止について配慮すること） 搬入する機材の大きさは、原則として通路の幅1.2m、高さ3mに適合すること PCV及びRPV内部に蓄積される可能性のある水素ガスについて配慮すること 燃料デブリ取出し作業開始時には、オペフロに100トン級の天井クレーンが設置済みで、使用済燃 料プール及び機器貯蔵プール内の使用済み燃料や機器は搬出済み 耐震安全性を考慮し、オペフロ等に新規に設置する機材等の総重量は極力少なくする バウンダリの検討において、オペフロを覆うコンテナには遮蔽機能及び気密機能を期待しない On-site operation condition After the start of the fuel debris retrieval, effective dose rate on the operation floor is 1mSv/h, 3mSv/h in operation area other than operation floor; and 5mSv/h in a passageway inside the building. No new openings, in principle, shall be created on the outer wall of the building. (Seismic resistance and prevention of leakage of radioactive substance should be considered, if new opening is indispensable.) Dimension of equipment to be brought in, in principle, shall meet with the passageway width of 1.2m and height of 3m. 60ｍSv/h From the bottom of 2-2.5m Unit 1 Reactor building 5th floor (Operation floor) From survey map of the building

13 Project 1 Conceptual Study of Innovative Approach for Fuel Debris Retrieval
Consider what we can do to retrieve the fuel debris assuming the water level inside PCV is the same as current measured or estimated one as of 2014.

14 Example of Innovative Approach
NB: This is an example. A proposal is NOT limited to this, and any feasible proposals are accepted. Fig Method of retrieving the fuel debris in the air from the top (fixed transport equipment)

15 Example of Innovative Approach
NB: This is an example. A proposal is NOT limited to this, and any feasible proposals are accepted. Fig Method of retrieving the fuel debris in the air from the top (mobile platform)

16 Example of Innovative Approach
NB: This is an example. A proposal is NOT limited to this, and any feasible proposals are accepted. Fig Method of retrieving the fuel debris in the air from the side

17 Goals and Objectives of C/S
Method of fuel debris retrieval Steps Layout Access Internal observation Debris cooling Collecting debris Retrieval technology Equipment Waste Items to be considered on safety operation Dose reduction Retention of boundaries Seismic safety Maintenance Hydrogen Development plan Others A scope of this C/S is a series of operations from delivery and installation of the equipment, fuel debris retrieval, and removal of used equipment.

18 Scope of C/S and F/S, and Requirements in RFP
Implemented in C/S and F/S The result of C/S and F/S should be equal or over the Goals and Objectives Goals and Objectives of C/S and F/S Additional Point Basic Point Implemented in RFP C/S： Conceptual Study F/S： Feasibility Study Basic Point All items should be filled out (No missing allowed to proceed to the step of proposal evaluation) Additional Point Optional Points are added according to the contents

19 Project 2 Feasibility Study of Visual and Measurement Technology for Innovative Approach
Visual and measurement technologies are requested to aim the challenging target specifications.

20 Measurement technology Measurement technology
Project Implementation - Scope of visual and measurement technologies - ・　 Usable under high radiation environment ・　 Compact and light-weight Common for visual and measurement technology ・　The equipment (with lighting function) shall be developed to detect conditions and locations of internal structures and the fuel debris in the PCV and the RPV. Visual technology ・　The equipment is required to be developed to distinguish fuel debris by its internal condition, external shape and properties. ・　The equipment to measure the radiation field around the objects to be cut, and to detect the hydrogen accumulation. Measurement technology 　Example of visual and measurement technology Visual technology camera, endoscope, and fiber scope Measurement technology radiation monitor, ultrasonic detector, laser scanner, radionuclide analyzer, thermography, and hydrogen concentration detector.

21 Target Specifications for Visual and Measurement Technologies
Severe conditions necessitate challenging specifications. Application process Application area Radiation resistance Basic shape Target object Status check of fuel debris PCV 1kGy/h or more 30kGy or more Dimension of X-6 opening (W550mm× H330mm) or less Internal structures and fuel debris RPV 10kGy/h or more 300kGy or more φ100mm or less Internal structures and fuel debris Fuel debris retrieval PCV, 10kGy/h or more 2MGy or more Radiation resistance (Cumulative dose rate) Operation hours to calculate cumulative dose rate are set as follows: Status check of the fuel debris： 1 day (24 hours) Fuel debris retrieval： 7 days (168 hour) Radiation resistance (dose rate) Status check of the fuel debris in PCV： About 10 times the air dose currently measured inside the PCV Fuel debris retrieval work and status check of the fuel debris in RPV： About 100 times the air dose currently measured inside the PCV Basic shape A basic shape of the equipment was determined envisaging the insertion of equipment from the existing opening.

22 Project 3 Feasibility Study of Fuel Debris Cutting and Dust Collection Technology for Innovative Approach Technology to be applied to cutting of various types of fuel debris is desired, as well as collecting and capturing resulted chips, crumbs, fumes, and dust.

23 Project Implementation
Uncertainties of fuel debris characteristics could be a key challenge for technology development. Cutting and Dust Collection Technology Usable under high radiation environment Capable of cutting fuel debris with different levels of hardness The function of collecting and capturing the resulted chips and crumbs, fume and dust need to be considered. Example of Cutting and Dust Collection Technology laser, plasma, core boring, and rock drill etc. Vickers Hardness in each Phase of Simulated Debris

24 Target object of Material
Target Specifications for Fuel Debris Cutting and Dust Collection Technology for Innovative Approach Application process Application area Target specification Radiation resistance Target object Target object of Material Cutting size Fuel debris retrieval PCV RPV 10kGy/h or more 2MGy or more Fuel debris Compound with different levels of hardness and brittleness in which boride, oxidized material, metal etc. are distributed heterogeneously 100 X100 X100 mm or less Target object of Material The material properties of fuel debris are based on the results of R&D for simulated debris addressed by a National Project. Vickers Hardness in each Phase of Simulated Debris Cutting size The cutting size is determined based on the capacity of fuel storage container used for TMI-2 『TMI Fuel Characteristics for Disposal Criticality Analysis（DOE/SNF/REP-084）』

25 Goals and objectives of F/S
Items to be studied in F/S of Project 2 and Project 3 are summarized as below. Basic principle and feasibility of the proposed technology Study of applicability of the technology to the site Study of schedule, project organization, and cost to realize the proposed technology

26 Summary RFP was launched on June 27, 2014 and will be closed on August 27, 2014. Considering the schedule to start the fuel debris retrieval expected in 2020, we’re awaiting many excellent proposals to arrive from Japan and from all over the world. Project 1: Conceptual Study of Innovative Approach for Fuel Debris Retrieval Project 2: Feasibility Study of Visual and Measurement Technology for Innovative Approach Project 3: Feasibility Study of Fuel Debris Cutting and Dust Collection Technology for Innovative Approach 26