Application of HiF Coat for Recontamination Reduction at

Background • Dose rate reduction effects don’t last long after operation. • Recontamination reduction

What is Hi-F Coat Film of Hi-F Coat Oxide film in plants Fe 3

Section photograph of film Formation of fine magnetite film（thickness：～ 0. 3μm） Outer (magnetite particle）

Reduction effect of activity deposition （laboratory data) Amount of 60 Co deposition (Bq/cm 2)

Outline of treatment procedure ＨＯＰ method Heat-up KMn. O 4 Base metal Fe 2

Outline of Hi-F Coat treatment equipments Only a little equipments are needed to decontamination

Outline of Hi-F Coat treatment chemicals Only iron formate is added to HOP method

Target of HOP decontamination & Hi-F Coat PLR piping ・PLR pump inlet & outlet

Hi-F Coat treatment conditions Parameter Planned value Measured value Fe conc. 250± 50 ppm

Hi-F Coat treatment results Test piece unit P P ※ この資料の複写、第 3者への公開を固く禁じます。 Surge tank

Hi-F Coat treatment results More than target value of 0. 1μm（60μg/cm 2) was achieved.

Surface observation (SEM) Before Hi-F Coat (After decon. ) After Hi-F Coat × 10000

Dose rate of PLR piping (1/2) ※ この資料の複写、第 3者への公開を固く禁じます。 All Rights Reserved. Copyright ©

Dose rate of PLR piping (2/2) ※ この資料の複写、第 3者への公開を固く禁じます。 All Rights Reserved. Copyright ©

Effect of dose rate reduction (1/4) Point 1: inlet piping ※ この資料の複写、第 3者への公開を固く禁じます。 All

Effect of dose rate reduction (2/4) Point 2: inlet piping ※ この資料の複写、第 3者への公開を固く禁じます。 All

Effect of dose rate reduction (3/4) Point 3: outlet piping ※ この資料の複写、第 3者への公開を固く禁じます。 All

Effect of dose rate reduction (4/4) Point 4: outlet piping ※ この資料の複写、第 3者への公開を固く禁じます。 All

Effect on chemical decontamination Hi-F Coat film was easy to be removed by chemical

Effect of Zn injection on Hi-F Coat 60 Co deposition amount (Bq/cm 2) Farther

Summary 1. Hi-F Coat was first applied to Shimane Unit 1 after chemical decontamination.

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Application of Hi-F Coat for Recontamination Reduction at Shimane Unit 1 Hitachi-ＧＥ Nuclear Energy, Ltd. M. Nagase, N. Usui, S. Oouchi Energy & Environmental Research Laboratory, Hitachi, Ltd. H. Hosokawa Chugoku Electric Power Company, Ltd. H. Kajitani, A. Yamashita, T. Minami ※ この資料の複写、第 3者への公開を固く禁じます。 All Rights Reserved. Copyright © 2009, 2008, Hitachi-GE Nuclear Energy, Ltd. 1 -0 0

　Background • Dose rate reduction effects don’t last long after operation. • Recontamination reduction is needed to keep low dose rate. ※ この資料の複写、第 3者への公開を固く禁じます。 All Rights Reserved. Copyright © 2009, 2008, Hitachi-GE Nuclear Energy, Ltd. 1 -1 11

　What is Hi-F Coat Film of Hi-F Coat Oxide film in plants Fe 3 O 4、 Fe 2 O 3、 Ni（Co)Fe 2 O 4 Outer Fe 3 O 4 Inner － Co. Cr 2 O 4、Cr 2 O 3 Size of particle ＜ 0. 2μｍ 1～ 10μｍ Thickness of film ＜ 0. 5μｍ 3～ 10μｍ Temperature 90℃ 280℃ Chemical form Principal of recontamination reduction Formation of fine outer magnetite film before power operation 　⇒Reduction of inner oxide film formation to pick up Ｃｏ Hi-F Coat : Hitachi Ferrite Coating ※ この資料の複写、第 3者への公開を固く禁じます。 All Rights Reserved. Copyright © 2009, 2008, Hitachi-GE Nuclear Energy, Ltd. 1 -2 22

　Section photograph of film Formation of fine magnetite film（thickness：～ 0. 3μm） Outer (magnetite particle） Coating layer (magnetite） Inner (chromite） Vapor deposited carbon Base metal（type 304 SS） Film formed under NWC 200ｈ (DO: 300 ppb) ※ この資料の複写、第 3者への公開を固く禁じます。 Vapor deposited carbon Base metal（type 304 SS） Film of Hi-F Caot All Rights Reserved. Copyright © 2009, 2008, Hitachi-GE Nuclear Energy, Ltd. 1 -3 33

　Reduction effect of activity deposition （laboratory data) Amount of 60 Co deposition (Bq/cm 2) ・Remarkable reduction of 60Ｃｏ deposition under HWC ・Continuous effect after ６ times of heat and cool（Stable) DO: <10 ppb, DH: 50 ppb, DH 2 O 2: 5 ppb Polished (no film) ～ 1/5 NWC treatment Hi-F Coat treatment Time (h) ※ この資料の複写、第 3者への公開を固く禁じます。 All Rights Reserved. Copyright © 2009, 2008, Hitachi-GE Nuclear Energy, Ltd. 1 -4 44

Outline of treatment procedure ＨＯＰ method Heat-up KMn. O 4 Base metal Fe 2 O 3，MFe 2 O 4 (M : Fe, Ni, Co) Oxidation Cr 2 O 3 Reduction, clean-up Dissolution of chromium oxides C 2 H 2 O 4 N 2 H 4 Repeat Base metal Hi-F Coat method Decomposition, clean-up Fe（HCOO）2 H 2 O 2 Hi-F Coat treatment N 2 H 4 Base metal Dissolution of iron oxides Base metal Decomposition Final clean-up ※ この資料の複写、第 3者への公開を固く禁じます。 Base metal Formation of fine ferrite (Fe 3 O 4) film All Rights Reserved. Copyright © 2009, 2008, Hitachi-GE Nuclear Energy, Ltd. 1 -5 55

　Outline of Hi-F Coat treatment equipments Only a little equipments are needed to decontamination equipments. Surge tank （with heater） Additional chemical injection system Catalyst column Pump Cooler Ion exchange column Target （PLR piping etc. ） Pump ※ この資料の複写、第 3者への公開を固く禁じます。 Filter All Rights Reserved. Copyright © 2009, 2008, Hitachi-GE Nuclear Energy, Ltd. 1 -6 66

　Outline of Hi-F Coat treatment chemicals Only iron formate is added to HOP method chemicals. HOP decon. process Hi-F Coat treatment process Chemical Conc. (ppm) KMn. O 4 200～ 300 For oxidation (COOH)2 2000 For reduction N 2 H 4 ～ 600 For ｐH control H 2 O 2 － Fe(HCOO)2 Remarks For decomposition of chemicals Fe：～ 250 Raw material for film formation Formic ion：～ Formic acid is used for LOMI* 500 process. H 2 O 2 － For ion value control N 2 H 4 200～ 500 For ｐH control *：LOMI is one of chemical decontamination method. ※ この資料の複写、第 3者への公開を固く禁じます。 All Rights Reserved. Copyright © 2009, 2008, Hitachi-GE Nuclear Energy, Ltd. 1 -7 77

Target of HOP decontamination & Hi-F Coat PLR piping ・PLR pump inlet & outlet ・Ring header ・Riser piping (A & B loops) ※ この資料の複写、第 3者への公開を固く禁じます。 HOP Hi-F Coat 1 st time 1 st &2 nd time All Rights Reserved. Copyright © 2009, 2008, Hitachi-GE Nuclear Energy, Ltd. 1 -8 88

Hi-F Coat treatment conditions Parameter Planned value Measured value Fe conc. 250± 50 ppm 263～ 296 ppm N 2 H 4 conc. 200～ 600 ppm 160～ 560 ppm ※ この資料の複写、第 3者への公開を固く禁じます。 All Rights Reserved. Copyright © 2009, 2008, Hitachi-GE Nuclear Energy, Ltd. 1 -9 99

Hi-F Coat treatment results More than target value of 0. 1μm（60μg/cm 2) was achieved. Sample item Application 1 st time 2 nd time Test piece 3 rd time 4 th time Temporary piping ※ この資料の複写、第 3者への公開を固く禁じます。 2 nd time 4 th time Sample No. 1 2 3 4 5 6 7 8 A B Deposited amount（ μg/cm 2) 230 270 302 192 125 132 402 498 150 359 All Rights Reserved. Copyright © 2009, 2008, Hitachi-GE Nuclear Energy, Ltd. 1 -11 11 11

　Effect on chemical decontamination Hi-F Coat film was easy to be removed by chemical decontamination. ※ この資料の複写、第 3者への公開を固く禁じます。 All Rights Reserved. Copyright © 2009, 2008, Hitachi-GE Nuclear Energy, Ltd. 1 -19 19 19

Effect of Zn injection on Hi-F Coat 60 Co deposition amount (Bq/cm 2) Farther Co deposition reduction can be expected with Zn injection. Time： 500 h Temp. ： 280℃ ECP：-0. 5 V 100 Polished Hi-F Coat 80 60 40 20 0 0 2 4 Zn conc. (ppb) ※ この資料の複写、第 3者への公開を固く禁じます。 6 Hitachi laboratory data All Rights Reserved. Copyright © 2009, 2008, Hitachi-GE Nuclear Energy, Ltd. 1 -20 20 20

Summary 1. Hi-F Coat was first applied to Shimane Unit 1 after chemical decontamination. 2. Hi-F Coat treatment was successfully applied to the decontaminated surface. Deposited amount of film was about 270 μg/cm 2 which was more than target value of 60 μg/cm 2. 3. Recontamination was suppressed about 1/2 to 1/3 after one operation cycle. 4. Coated film was easy to be removed by chemical decontamination. 5. Farther dose rate reduction can be expected with Zn injection. ※ この資料の複写、第 3者への公開を固く禁じます。 All Rights Reserved. Copyright © 2009, 2008, Hitachi-GE Nuclear Energy, Ltd. 1 -21 21 21