corrosion in upstream oil and gas industry[1]
DESCRIPTION
corrosionTRANSCRIPT
Deden Supriyatman
Vice President of Indonesian Corrosion Association
Presented in “The 2nd NDT - Corrosion Management Asia Conference & Exhibition”
Singapore, 7-8 December 2006
Corrosion in Corrosion in UpstreamUpstream OilOil & & GasGas IndustryIndustry: : SomeSome Key IssuesKey Issues
2nd NDT/Corrosion Management Asia Conference and Exhibition 2006, Orchad Hotel, Singapore 7-8 Dec 2006
2nd NDT/Corrosion Management Asia Conference and Exhibition 2006, Orchad Hotel, Singapore 7-8 Dec 2006
2nd NDT/Corrosion Management Asia Conference and Exhibition 2006, Orchad Hotel, Singapore 7-8 Dec 2006
Corrosion: how much does it cost ?
Too much ! An indisputable though imprecise affirmation 0.35 USD/boe: a precise, but hard to grasp affirmation15 million USD/year in corrosion prevention chemical alone25 million USD/year in regular paint maintenance expenditure1.4 billion USD/year in the US for upstream oil & gas sector alone out of 276 billion USD/year in total corrosion cost
2nd NDT/Corrosion Management Asia Conference and Exhibition 2006, Orchad Hotel, Singapore 7-8 Dec 2006
Oil & GasExploration Production
$1.4 Billion Per Year
2nd NDT/Corrosion Management Asia Conference and Exhibition 2006, Orchad Hotel, Singapore 7-8 Dec 2006
• Operation, Maintenance, Finance, Capital
•Surface Piping & Facility Costs M$589
•Downhole Tubing Expenses M$463
•Capital Expenses M$320
TOTAL B$1.36
Sector Summary: Oil & Gas
• Relative High Costs of Oil & Gas Production in the U.S.
•Maintenance Costs Must be Kept to a Minimum
•Emphasis on Controlling Internal Corrosion with Corrosion Inhibitors
2nd NDT/Corrosion Management Asia Conference and Exhibition 2006, Orchad Hotel, Singapore 7-8 Dec 2006
Wells, surface facilities (including pipelines) with high qualities are vital to oil and gas business as they contribute over their life cycle and optimum monetary value without compromising safety and environment standards.
Material degradation (read: corrosion) in the wells and pipelines have to be minimized through proper selection of materials.
Such proper selection (several alternatives) has to be based on mechanical and metallurgical properties lead to technically and economically sound final choice.
2nd NDT/Corrosion Management Asia Conference and Exhibition 2006, Orchad Hotel, Singapore 7-8 Dec 2006
• Advance design practices for better corrosion management
• Advance life prediction and performance assessment methods
• Advance corrosion technology through research, development, and implementation
Technical Preventive Strategies
• Increase awareness of the large corrosion costs and potential savings
• Change the misconception that nothing can be done about corrosion
• Change policies, regulations, standards, and management practices to increase corrosion savings
• Improve education and training of staff
Non-Technical Preventive Strategies
2nd NDT/Corrosion Management Asia Conference and Exhibition 2006, Orchad Hotel, Singapore 7-8 Dec 2006
Corrosion by H2S
Sour service is defined with respect to corrosion cracking related to Sulfide Stress Corrosion (SSC).SSC mainly affects high resistance carbon steels but also corrosion resistance alloys.
This phenomenon is characterized by a rapid crack evolution in the steel during and after H2S exposure leads to quick failures in hours to days:
- Sufficient H2S Partial Pressure (< 0.05 psi or 0.0035 bar)
- Considerably Low Fluid pH ( < 3.5)- Low Temperature (< 65 deg C)- H2O Presence
2nd NDT/Corrosion Management Asia Conference and Exhibition 2006, Orchad Hotel, Singapore 7-8 Dec 2006
Service Condition: SourpH-pH2S domain diagram (ISO 15156, NACE MR 0175)
- Zone-0 Sweet Service(only trace H2S): no specific metallurgical pre-caution unless pH < 3.5
- Zone-1 Mild Sour Service (minor precau-tion)- Zone-2 Intermediate Sour Service (increasing precaution is needed)- Zone-3 Severe Sour Service (most stringent precaution is necessary)
2nd NDT/Corrosion Management Asia Conference and Exhibition 2006, Orchad Hotel, Singapore 7-8 Dec 2006
Reference: ISO 15156 & NACE MR 0175
2nd NDT/Corrosion Management Asia Conference and Exhibition 2006, Orchad Hotel, Singapore 7-8 Dec 2006
BESIDE H2S, THE COMMON CORROSIVE AGENT IN THE WORLD ’S HYDROCARBON AND PROCESS SYSTEM IS CO2. THIS IS THE MOST FREQUENT TYPE OF INTERNAL CORROSION BY OIL AND GAS EFFLUENTS. IT IS A HIGHLY COMPLEX PHENOMENON A TYPE OF ACID CORROSION INFLUENCED BY ITS PARTIAL PRESSURE , ITS TEMPERATURE AND CHEMICAL COMPOSITION OF WATER (pH, ORGANIC ACID,..)
Partial Pressure
H2S
CO2 + H2S
Corrosion Rate
CO2
Corrosion by CO2
2nd NDT/Corrosion Management Asia Conference and Exhibition 2006, Orchad Hotel, Singapore 7-8 Dec 2006
NO CO2 CORROSION PREDICTION MODEL ACCEPTED BY EVERYONE, BUT SOME EMPIRICAL CORROSION RATE (CRt) CALCULATIONS HAVE BEEN DEVELOPED AT THE VARIOUS TEMPERATURES, pH, CO2 FUGACITIES, WALL SHEAR STRESS,…
EACH COMPANY USING ITS OWN MODEL RESULTING FROM ITS OWN EXPERIENCE.
2nd NDT/Corrosion Management Asia Conference and Exhibition 2006, Orchad Hotel, Singapore 7-8 Dec 2006
CORROSION CALCULATION/ MODEL & CORRECT INPUT DATA
CONSTRUCTION & COMMISIONING CONDITION
CONSIDERATION OF NORMAL AND UPSET OPERATING CONDITION e.g. UPHEAVAL BUCKLING
ACTUAL CORROSIVITY OF PRODUCED FLUID & CORROSION INHIBITOR EFFICIENCY
GEOMETRY OF CORROSION ATTACK e.g. TOP OF LINE CORROSION
2nd NDT/Corrosion Management Asia Conference and Exhibition 2006, Orchad Hotel, Singapore 7-8 Dec 2006
Definition : “Uplift of a restrained pipeline induced by expansion due to pressure & temperature and initiated at foundation imperfections”
Parameters :
Operating temperature higher than ambient
High pressure
Imperfection of the soil
Expansion
Axial restraint (friction)
Axial Compressive
Load
Vertical components exceed soil resistance
What is a Upheaval Buckling and why did it formed ?
2nd NDT/Corrosion Management Asia Conference and Exhibition 2006, Orchad Hotel, Singapore 7-8 Dec 2006
• - corrosion / erosion• - impact / navigation hazard• - static loading• - fatigue and plastic collapse
• - rupture• - safety and environment issues• - loss of production
Consequence
Problem
Risks Associated with Upheaval Buckling
2nd NDT/Corrosion Management Asia Conference and Exhibition 2006, Orchad Hotel, Singapore 7-8 Dec 2006
WaterCondensateGas phase
FlowT1, P1 T2, P2
Condensed waterStagnant pittingsTrickling uniform corrosion
Inhibited condensate
Inhibited free water
Heat fluxHeat flux
Flowing conditions favouring Top of Line Corrosion– Stratified flow regime: water-saturated gas phase segregated
from liquid phases flowing underneath– Cooling due to heat transfer to the ambient media– Top of Line Corrosion = Internal corrosion in the upper part of
the pipe (between 9 o'clock and 3 o'clock), due to water condensation
2nd NDT/Corrosion Management Asia Conference and Exhibition 2006, Orchad Hotel, Singapore 7-8 Dec 2006
So…to repeat:
1. H2S and/or 3. O2 and/or2. CO2 and/or 4. Organic Acid
Material degradation (read: corrosion) in oil & gas industry requires generally the presence (in addition to other factors including H2O) of the following component(s) :
2nd NDT/Corrosion Management Asia Conference and Exhibition 2006, Orchad Hotel, Singapore 7-8 Dec 2006
Microbiologically Induced CorrosionThe chloride ions, films of scales as well as bacteria leading to Microbiological Induced Corrosion (MIC) may also be involved in material degradation, although they are less frequent than the above 4 main components.
2nd NDT/Corrosion Management Asia Conference and Exhibition 2006, Orchad Hotel, Singapore 7-8 Dec 2006
The corrosion inhibitor selection equipment is beneficial for servingeducation (graduates and post-graduates) and industrial needs (manycompanies use this university’s expertise using such useful tool)
Beside in-house one, the researches (supported by petroleum industry) in university on corrosion aspect is worth considering…
Exploit University Technologies to Serve Industries…Good proactive example: ITB with TOTAL E&P INDONESIE
2nd NDT/Corrosion Management Asia Conference and Exhibition 2006, Orchad Hotel, Singapore 7-8 Dec 2006
Final Remarks
1. The fluid contact, acid, predicted service condi-tion, and other risks for upstream (pipelines, casing and tubing of new well under development) must be assessed.
2. Material selection including corrosion mitigation method has been of paramount importance. It could be : (a) do nothing else than applying a carbon steel material accepting future failure and replacement, (b) treat the fluid or service condition, (c) use of CRA.
3. Study in detail on the subject including cost evaluation is strongly advisable.
2nd NDT/Corrosion Management Asia Conference and Exhibition 2006, Orchad Hotel, Singapore 7-8 Dec 2006
Final Remarks - cont
4. Think Safety & Environment (S&E) ! Corrosion cost figures presented above, they are nothing in comparison with those that may result from a major failure (leaking export pipelines, production tubing or pressure vessels, deterioration of an FSO or FPSO …), the economic impact of which may quickly exceed hundreds million USD in addition to the potential repercussions in terms of S&E.
5. R&D Programs (including with universities). It has to be devised and implemented in parallel to investigate solutions.