High Wet CO2 + H2S Gas High Wet CO2 + H2S Gas Vs Latest NACE 1075Vs Latest NACE 1075--20032003

atatCustomer seminar Nov. 13 2006Customer seminar Nov. 13 2006

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A. Kobori

2AgendaAgenda

1. NACE Old Vs New

2. Material selection by NACE Vs DR

3. High CO2 + H2S Gas Vs Latest NACE

4. Conclusion for material selection for High CO2 +H2S

3H2S Stress Cracking Corrosion( SSC)H2S Stress Cracking Corrosion( SSC)

Intergranular H2S Cracking, Intergranular H2S Cracking, SEM, x1000 magnificationSEM, x1000 magnification

Depth of Sulfide Stress CracksDepth of Sulfide Stress Cracks

4HH22S Crack test S Crack test --1972 in Japan1972 in Japan

7090

110130150170190

0.001 0.01 0.1 1

H2S partial pressure-psi

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AISI 4330

17-4PHMaterialAISI-4140

Remark: 0.05psi=0.3kPA,

We made 100KSI YP with AISI4330 and

105-115KSI YP with 17-4PH in old day

5NACE NACE --97 Vs NACE97 Vs NACE--20032003

(pCO2+pH2S) Vs pHN/AFig.D.1

pH2S Vs pHpH2S Vs PressureFig.1 for SSC by H2S

SSC by H2S,

SSC& CRA by (H2S+CO2)

SSC by H2SObject

H2S, H2S+CO2

H2S+Others

H2SWet Sour Gas

NACE MR0175/ISO 15156-3-2003EO

NACE MR-0175-97Title

6Fig 1 for H2S SSC by NACE Fig 1 for H2S SSC by NACE --9797

Note: 0.05psia= 0.3 kPA)

7Fig.1 of NACE 2003, H2S partial pressure Fig.1 of NACE 2003, H2S partial pressure Vs in situ pH for H2S SSCVs in situ pH for H2S SSC

Figure 1- NACE 2003

2.5

3.5

4.5

5.5

6.5

0.01 0.1 1 10 100 1000

H2S Partial Pressure kPa

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0.3

Region 0

Region 1

Region 2

Region 3

Note: Region 0,pH2S

8SSC Region by Fig .1 of NACESSC Region by Fig .1 of NACE--20032003

SSC Region 0: pH2S < 0.3kPa (0.05psi), No precaution for selection of material

SSC Region 1: Material from A.2, A.3 or A.4 steels

SSC Region 2: Material from A.2 or A.3 steels

SSC Region 3: Material from A.2

Where A.2 is for SSC(sulfide stress cracking corrosion) resistant & low alloy steel. A.2 is consistent with a previous established requirement of NACE MR0175

A.3 is SSC resistant steels through out Region 2

A.4 is SSC resistant steels through out Region 1

A.2,A.3 &A.4 is in Annex A of Part B of NACE 2003

Important: Fig.1 of NACE 2003 is only for gas containing H2S

9What is pH ?What is pH ?

Definition : pH = -Log[H+]

pH 0 1 2 3 4 5 6 7 8 9[H+] 1 10-1 10-2 10-3 10-4 10-5 10-6 10-7 10-8 10-9

AlkaliAcidpH < 3.5: Strong Acid

Neutral : [H+] = [OH-]=10-7 gram ion/Liter

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NACENACE--2003 ,Annex2003 ,Annex--D introduced pH of D introduced pH of condensed water under CO2 and H2S Pressurecondensed water under CO2 and H2S Pressure--1/21/2

Fig. D.1

100C

20C

Fig D.1 chart need to convert to Equation for practical usage!

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NACENACE--2003 ,Annex2003 ,Annex--D introduced pH of D introduced pH of condensed water under CO2 and H2S Pressurecondensed water under CO2 and H2S Pressure--2/22/2

Value below is read from Chart and converted into formula.pCO2+pH2S-kPa 0.1 1 10 100 1000 10000 600 0.3 2023 Temp

pH 5.36 4.87 4.39 3.89 3.4 2.91 3.5 5.13 3.25 At 20 CpH N/A 5.11 4.62 4.13 3.64 3.15 3.74 5.37 N/A At 100 C

Note: Fig. D-1 Chart is redrawn by KL

A. Proposed calculation formula based on approximation from D.1 Chart from NACE ( by AK on Feb

Y = - 0.49 Log 10 X + 4.87.( 1) for T= 20CY = - 0.49 Log 10 X + 5.11.( 2) for T= 100C

where Y: The pH of condensed water under CO2 & H2S X: pCO2 + pH2S in kPA

The pH at 20degC

234567

0.1 1 10 100 1000 10000pCO2+pH2S in kPA

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To determine Wet or Dry at InletTo determine Wet or Dry at InletH2O Saturation Temp Vs Pressure

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Temperature-degC

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Temp-C kg/cm2A kPA PSIA6.7 0.01 0.98 0.14

17.202 0.02 1.96 0.2823.771 0.03 2.94 0.4332.55 0.05 4.9 0.7138.66 0.07 6.86 0.9943.41 0.09 8.82 1.2849.05 0.12 11.77 1.7154.93 0.16 15.69 2.2759.66 0.2 19.6 2.8465.43 0.26 25.5 3.775.41 0.4 39.22 5.6980.86 0.5 49.03 7.11

Pressure

Note: H2S SSC and H2CO3 corrosion only occur at presence of water

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TableA.1:Guide to material selection TableA.1:Guide to material selection from Annex A of NACE 2003from Annex A of NACE 2003

Table A.30Table A.22Table A.6Compressor Component

Table A.26Table A.18Table A.2Any Equipment or Component

Precipitation Hardened S.Steel

Martensitic S.Steel

Austenitic S.Steel

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Martensitic Stainless SteelMartensitic Stainless Steel

Table A.22-Compressor component Alloy UNS No pH2S max-kPa pH Sulfur resistant? S41000 J91540 (CA6NM) S42400 (F6NM)

See remarks

See remarks

No data submitted

Table A.18- Any equipment or component Alloy UNS No pH2S max-kPa pH Sulfur resistant? S41000 J91540 (CA6NM) S42400 (F6NM)

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3.5

No data submitted

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Precipitation Hardened Precipitation Hardened S.SteelS.SteelTable A.27-Wellhead,Christmas tree component, valves& other subsurface equipment Alloy UNS No pH2S max-kPa pH Sulfur resistant? S 17400 3.4 4.5 No data submitted Note: Table 26 is for material of UNS S 66286 which is not applicable to DR. Table A.30-Compressor component Alloy UNS No pH2S max-kPa pH Sulfur resistant? S 17400 See remarks See remarks No data submitted

() Our interpretation of NACE 2003 for Martensitic and hardened precipitation S. Steel S17400 (17-4PH) is good for pH max of 4.5 by NASE. S41000( AISI410 ) is good for pH max of 3.5 by NACE. DR has same criteria J91450 (CA6NM) is good for pH max of 3.5 per NACE, but is operated at lower pH for

Shell job S42400(F6NM) is good for pH max of 3.5 per NACE, but is OK for max pH of 3.29 by

DR, Further it is under NACE testing in Olean. June 2006 will know result N07718 ( 718 Inconel) is good for pH lower up to 2.5 by DR

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DD--R metallurgist view for 410 SSR metallurgist view for 410 SS

1E-3 0.01 0.1 1 10 1002.5

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410 Stainless Steel NACE Testing

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H2S Partial Pressure (bar)

Fail, 0 PPM Chloride Fail, 100 PPM Chloride

Nace MR0175 Approved

410 is good for max. pH 3.5 with max H2S partial pressure of 0.1Bar(10kPA) based on NACE test

F6NM NACE test is good for max. pH 3.29

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High CO2 Gas+H2S Vs NACEHigh CO2 Gas+H2S Vs NACE

Check of past successful 100% CO2 gas with Equation 1 derived from Fig.1

pH calculation and comment for On-going project with high CO2+H2S

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pH pH CheckCheck for past CO2 compressorsfor past CO2 compressors--1/21/2pH = -0.49Log10 X + 4.87 which is equal to Fig. D.1 of NACE 2003.

Contract/ Ship Comp Section psia kPa4M9-5 1 15.5 106 131 3.87 AISI4103M10-7 2 63.6 438 109.4 3.57 AISI410

3 248 1709 109.4 3.28 AISI4104 1041 7177 129 2.98 AISI410

3M4-3 1 16.8 116 109.4 3.85 AISI410553B10-8 2 59.3 409 115 3.59 AISI410

3 203 1399 115 3.32 AISI4104 687.4 4739 115 3.06 AISI4101 20.4 140 113 3.81 AISI4102 66.1 456 113 3.56 AISI4103 240.9 1661 113 3.29 AISI4104 896.5 6181 113 3.01 AISI4101 20.8 143 107.6 3.81 AISI4102 104.95 724 107.6 3.46 AISI4103 406 2799 107.6 3.18 AISI4104 1250.3 8621 131 2.94 AISI4101 23.3 161 103 3.78 AISI4102 103.5 713 104 3.47 AISI4103 347.7 2397 104 3.21 AISI4104 1047 7219 122 2.98 AISI410

1st Stg Ps Ts-deg F pHcalculatedActualImpeller

MDR-1020C,1994

MDR-1016,1993

DML-6130E,1982

CT21124,1981

DML-6073E,1977 272B6/4

161B5/5

3M9-7

26.08B5/4

272B5/4

3M8-7

26.08B5/4

3M8-7

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pH for 100% wet CO2 application fallen into pH lower than 3.5 , but all units are operating well with S41000( AISI 410) impeller material. Note Table 18 for 410 says pH 3.5

As stated in para 8.2 of NACE 2003 ( Qualification based upon field experience) and wet CO2 gas is only contribute to

corrosion in lieu of stress cracking corrosion, we can conclude that pH judgment for wet CO2 gas is not correct method

pH Check for past CO2 compressorspH Check for past CO2 compressors--2/22/2

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Thank You.Thank You.

www.dresser-rand.cominfo@dresser-rand.com

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