Top Banner
25

Abstract of Papers:- - Malaysian Gas · PDF fileAbstract of Papers:-PETRONAS Carigali Sdn Bhd, Sarawak Operations (PCSB SKO) operates predominantly aged offshore pipelines principally

Mar 06, 2018

Download

Documents

phungnhu
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
  • Abstract of Papers:-

    PETRONAS Carigali Sdn Bhd, Sarawak Operations (PCSB SKO) operates predominantly

    aged offshore pipelines principally for oil and gas evacuation in Sarawak Malaysia. By

    implementing an integrated approach to pipeline integrity management comprising

    rigorous inspections, fitness for service assessments and risk assessments; a risk based

    asset integrity management programme has been developed which has enabled PCSB

    to prioritize and optimize pipeline integrity management with the objective of

    reducing incidents of pipeline failures and at the same time achieve life extension.

    The predominant integrity threat for the pipeline assets has been microbial influence

    corrosion (MIC). The integrity management programme implemented has enabled

    PCSB SKO to assess the pipeline asset risks to MIC as well as prioritize and optimize the

    internal corrosion mitigation programme.

  • An Integrated Approach to Managing the Integrity of Offshore Pipelines.

    Mohamed Amin Abdullah

    Head of Sarawak Operations

    PETRONAS Carigali Sdn Bhd

    7th APCE, 11th October 2011, Kuala Lumpur

  • Overview of PETRONAS Carigali Sarawak Operations (SKO) and its

    Pipeline System

    Primary Integrity Threats and Pipeline Condition Assessment

    Strategy.

    MIC Prediction

    Integrity Management Approach - Detection and Mitigation Strategy

    A Case Study

    Summary and Conclusion

  • Source: Regional pipeline data

    PCSB Sarawak Operation (SKO) involves in

    managing predominantly aging pipeline assets

    SKO Pipelines (1477km , 172 nos.)

    Size

    (in dia.)Up to 36

    Age

    (years)

    < 20 20-30 > 30

    47 58 67

  • PCSB Sarawak Operations operates about 1500 km of offshore pipelines

    connected to Crude Oil Terminals in Miri and Bintulu

    SKO Gas Customers

    Helang Layang

    B12B11

    Laila

    D21 D30

    D18

    Temana

    D28

    J4

    D35

    D16

    Bayan

    Hasnah

    Lembuk

    Sikau

    Siwa

    Fairley Baram

    D51D5D26

    D41

    D12

    D2

    S. Acis

    Singa Laut

    Patricia

    Sompotan

    Serunai

    Geduk

    N. AcisE2

    Gambang

    Sapih

    W. Lutong

    Tukau

    Bokor

    Betty

    ASAM PAYA

    Fatimah

    Merak

    Beryl BaroniaBaram

    Bakau

    Mawar

    Lemai

    BINTULU

    MCOT

    MIRI

    LUTONG

    D34

    MLNG

    MLNG-TIGA

    BCOT

    Not to scale

    MLNG DUA

    TK/SI

    F6

    F13

    E8

    Sh. ClasticsE6

    F28

    E4

    F23SW

    E11R-C

    E11R-B

    E11R-AE11

    JintanSerai

    F23Cili Padi

    M3M5G7

    M4

    F29

    F12

    F11F14

    F9

    Lada Hitam

    Selasih

    B.Sawi

    Bijan

    Bunga Pelaga

    M1

    F27F22

    Saderi

    Bokor South

    Tukau Timur

    Bakau Deep

    Bario

    J1

    J5

    J32

    J2

    K5

    Tenggiri Marine

    A21

    A23

    K4

    BentaraBalai

    J12Yu

    C13

    C2

    Selar Marine

    Jerong Marine

    OBO

    COB

    COB

    SarawakBrunei

    SKO Crude Customers

    ABF SMDS MLNG

    Crude Oil Group (COG)

    PC4

    Kumang

    PCPP SK305 Block

    Dana

  • CPIMS Enhancement

    Corrosion Management

    (product / process

    monitoring, cleaning, inhi

    bition / biociding)

    Internal Inspection

    External Inspection

    Contingency material &

    repair

    Pipeline/facility

    Rejuvenation and

    replacement

  • What is MIC?

    Microbial Influenced Corrosion (MIC): a

    modified form of localised corrosion that

    is enhanced by bacteria activity.

    In crude oil and water injection pipelines,

    Sulphate Reducing Bacteria (SRB) is a

    primary source.

    Growth and activity requires:

    - Water

    - An energy source (e.g. Light)

    - A carbon source (e.g. CO2)

    - An electron donor (e.g. organic /

    inorganic substrate)

    - An electron acceptor (e.g. SO4-, O2)

    J Healy et all. Development of appropriate inspection and maintenance options to mitigate microbial induced corrosion (MIC) in offshore oil pipelines. 4th Annual Middle East Pipeline Integrity Management Summit, Abu Dhabi, 23-24 February 2009

  • Primary Threats are internal corrosion (sub-sea

    pipelines) and external corrosion (risers)

    Primary cause of internal corrosion attributed to MIC

    This paper is focused on internal corrosion.

  • Typically the corrosion pits due

    to MIC tend to be small (8 15

    mm in diameter) and

    hemispherical in shape.

    Occurrence along pipeline can

    be random (low points, areas

    of low or stagnant flow) where

    biofilms could be established

    Recent experience of corrosion

    rates (unmitigated) due to MIC

    are in the range 0.5 to 6 mm/yr.

    Premature pipeline failures

    recorded (as early as 4 years

    after installation)

    SKO experienced very high corrosion rates

    including failures due to MIC

    ILI data showing Corrosion Growth

    Rates of 0.5 to 3mm/yr

    J Healy et all. Development of appropriate inspection and maintenance options to mitigate microbial induced corrosion (MIC) in offshore oil pipelines. 4th Annual Middle East Pipeline Integrity Management Summit, Abu Dhabi, 23-24 February 2009

  • Concentration of localised pits at the bottom of pipeline is

    a typical pattern of MIC from internal Inspection (IP)

  • MIC associated with deep pitting and high corrosion growth rates major implication on safe operation and remaining life prediction.

    MIC on older assets (>25 years old) experienced change in operations parameter, contamination of well and processing facilities.

    Such assets traditionally designed for CO2 (sweet) corrosion with no cleaning & biocide treatment facilities.

    Once established, MIC is difficult to control (no easy access to treat deep pits by cleaning and biocide dosing)

    Low flow rates also a major issue in achieving effective cleaning / water removal and biocide treatment.

  • Structured approach to assess the MIC susceptibility

    Risk Assessment to prioritise high risk / criticalpipelines.

    Inspection & condition assessment.

    Integrity (FFS) Assessment / Root Cause Diagnosis

    Mitigation Strategy to include feedback to enableeffectiveness of the Corrosion Management Plan(CMP) to be monitored and adjusted as appropriate.

    Pipeline Rejuvenation

  • MIC Prediction using monitored data has enabled quick

    identification of affected pipelines for treatment

    Sampling / Monitoring conducted for several of the field.

    Relationship between available nutrients, bacteria counts,

    other operational data and perceived risk established.

    Key issues identified:

    No water separation offshore

    Water injection and well contamination

    Recommendation for control / mitigation

    BiDi OP brush tool + biocide.

    Monitoring and condition assessment including

    Inspection frequencies (IP & UT).

  • SKO Wide Risk Assessment is used to rank and

    prioritize the pipelines for treatment

    Risk Assessment to prioritise high risk / critical pipelines.

    In-line Inspection to quantify the pipeline condition, risk level and extent of damage.

    Based on inspection data, evidence to diagnose (or otherwise) whether MIC is present

    Integrity (FFS) Assessment to define long term remedial and Corrosion Mitigation Strategy

    Rejuvenation to provide facilities for full CMP implementation.

  • Options:

    In-line inspection along length of the pipeline

    UT inspection at local high risk areas?

    Techniques:

    Conventional in-line Ultrasonic's (UT) or Magnetic Flux Leakage (MFL)

    Tethered UT

    Localised subsea external UT

  • Based on inspection data, evidence to diagnose whether MIC is present

    Immediate repair / investigation priorities is scheduled

    Based on available pipeline information, Corrosion Growth Rates can be estimated

    Operating conditions Monitoring information Corrosion modelling Detailed comparison of

    inspection data,

    Future repair priorities can be defined, together with revised Corrosion Management Plan (CMP).

    Inspection 1

    Inspection 2 Growth of Existing Features

    Growth of New

    Feature

    Inspection 1

    Inspection 2 Growth of Existing Features

    Growth of New

    Feature

  • A Case Study : 18 Crude Oil Pipeline.

    18 x 55km crude oil line with a design life of 30 years

    In service since 1983 (19 years at time of first inspection 2002)

    Transport crude oil, water cut 17%, pH 6.86, CO2 1.27 mole%

    No inhibitor / biocide applied.

    Operational cleaning & water removal with Bi-Di tool conducted

    monthly

    MIC Risk Assessment indicated HIGH risk level.

    First in-line inspection conducted in 2002 and repeat inspection

    conducted in 2007 using IP and Calliper tools.

    Survey of Cathodic Protection system indicated that the pipeline was

    adequately protected subsea.

  • IP result and its interpretation is used to

    determine major internal corrosion threat.

    Re-inspection in 2007,

    indicated significant increase

    in internal corrosion features

    (from 3,944 in 2002 to 26,276

    in 2007) Deepest Feature

    46%.

    Indicative of severe internal

    corrosion activity o