MANAGING CORROSION CHALLENGES ASSOCIATED WITH HEAT EXCHANGERS - GCC Chapter
MANAGING CORROSION CHALLENGES ASSOCIATED WITH HEAT EXCHANGERS For Presentation at GPA-GCC Special Session on Corrosion Management in Gas Processing Facilities Manama, Bahrain November 28, 2007 M. A. Saleem & A. A. Hulaibi Saudi ARAMCO Uthmaniyah Gas Plant Southern Area Gas Operations
Outline Objective Operational Criticality Functionality of Heat Exchangers Corrosion Challenges Root Causes Corrosion Management Strategies Integrity Management Program Conclusions
Objective Review Corrosion Challenges Associated with Heat Exchangers and the Integrity Management Programs being implemented for Safety & Reliability Enhancement.
Process Overview C2 to Yanbu & Ju'aymah C2 sphere C2 NGL To Sales Gas Grid HP Fuel Khuff Gas Khuff Conditioning Cond to Crude Inj Associated Gas Slug Catchers LP Fuel H P Chilldown D G A Sweet Gas G a s T r e a t Sales Gas Comp. SEC Power Generation Fuel Gas Comp. In-Plant Fuel Usage Acid Gas Sulfur Recovery Sulfur to Truck Loading
Functionality of Heat Exchangers Heat exchangers (HE) are crucial for plant Operations. HE help to achieve: Heat transfer between two process streams Phase transformation
Types of Heat Exchangers HE are of different types and the design depends on Process requirements. Air Cooled Shell & Tube Double Pipe Plate & Frame Based on the application, HE are categorized as: Condenser, Reboiler, Cooler, Chiller, Evaporator/Vaporizer, Steam Generator, Heater, Waste Heat Boiler
Air Cooled Heat Exchanger Air Seal Tube Keeper (top) Lifting Lug Air Seal Header Tube Nozzle Header Fins Tube spacer Side Frame Tube Support (bottom) Air Seal
Shell and Tube Heat Exchanger Tube side Flow Out Shell side Flow In Shell Tube Bundle Shell side Flow Out Tube side Flow
Double-Pipe Heat Exchanger Shell Cover Gasket Vent External Fin Pipe Shell Shell Cover Return Bend (welded) Drain Sliding Support Twin Flange Fixed Support Shell End Piece
Plate and Frame Heat Exchanger Aout Bin Nozzle Header Separating Sheet Cin Corrugated Sheet Effective Width Heat Transfer Section Effective A Length Side Bar Distributor Distribution Section Cout Bout Ain B
Corrosion Challenges: Critical HE Hydrocarbon Service Propane Condensers Stripper Overhead Condenser Amine Service Lean Solution Coolers Cooling Water Service Cooling Water Heat Exchangers Cooling Tower Steam/BFW Service Sulfur Condensers Boiler Feed Water Heat Exchangers Condensate Reboilers Regen Steam Condensers
Propane Condenser HE Type: Air Cooled Service: Propane Material: Carbon Steel (with Al Fin on the external) Number of Tubes: 220 per bank Total No of Tubes: 220 x 48 banks 10,560 tubes Mode of Attack: Internal Pitting
Propane Condenser Tube
Internal Corrosion - Pitting
Internal Pit Penetration ID OD
Propane Condenser Tube Inspection Metal Loss Æ 20% 20-40% 40-60% 60% Inspected Restricted E-161A 2,559 2,270 378 66 5273 7 E-161B 1,247 2,144 458 109 3958 2 Total # of 3,806 Tubes 4.414 836 175 9231 9
Propane Condenser Tube Assessment 3000 2500 # of Tubes 2000 1500 1000 500 0 20% 40-60% Restricted % Metal Loss (Corrosion) E-161A E-161B
Prop Condenser Tube Corrosion Review Internal Corrosion Process Contaminants: H2S & Moisture Source of Contaminants: ¾ From Condensate Stripper ¾ Propane Make-up stream From Depropanizer Resolution: Source of contaminants eliminated by Rerouting
Lean Amine Cooler HE Type: Air Cooled Service: Lean DGA Material: Carbon Steel (with Al Fin on the external) Number of Tubes: 258 per bank Total No of Tubes: 258 x 40 banks 10,240 tubes Mode of Attack: Tube-end Erosion (1st Row) Fouling
Lean Amine Cooler
Lean Amine Cooler Tub-end Deterioration
Lean Amine Cooler Tube-end Restoration
Lean Amine Cooler Corrosion Review Internal Corrosion: Tube-end Erosion ¾ Increased Velocity ¾ Suspended Solids Fouling due to: ¾ Corrosion Products ¾ Heat Amine Stable Salts
Sulfur Condenser HE Type: Shell & Tube Service: Shell side: Boiler Feed Water Tube side: Acid gas/Sulfur Material: Carbon Steel Number of Tubes: 3159 Mode of Attack: Pitting
Sulfur Condenser
Sulfur Condenser Tube – External Pitting
Sulfur Condenser Corrosion Review Shell side (Tube External) Corrosion ¾ Dissolved Oxygen ¾ Lack of Adequate Treatment Internal Corrosion: ¾ Under deposit
Closed Recirculating Cooling System To Cooling Tower Heat Exchanger Batch Chemicals From Cooling Tower Make-up Water Surge Tank Pumping Station
A Typical Cooling Water System
Cooling Water Heat Exchanger HE Type: Shell & Tube Service: Shell side: Cooling Water Tube side: Cooling Tower Water Shell/Tube sheet Material: Carbon Steel Bundle Material: Aluminum Bronze Number of Tubes: Mode of Attack: Localized Tube sheet Deterioration
CW Heat Exchanger Tube sheet
CW Heat Exchanger Tube sheet
CW Heat Exchangers – Tube sheet
CW HE Tube sheet – After Restoration
Heat Exchanger Restoration
Cooling Tower Type: Cross flow Cooling Tower Service: Cooling Water Tube side: Cooling Tower Water Material: Redwood Number of Tubes: 1595 Mode of Attack: Chemical & biological
Cooling Tower Structure & Basin
Cooling Tower Wood Deterioration
Treated Wood -Susceptibility to MIC
Boiler Feed Water Heat Exchanger HE Type: Shell & Tube Service: Shell side: Steam Condensate Return Stream Tube side: Boiler Feed Water Shell Material: Carbon Steel Tube Material : Aluminum Bronze Number of Tubes: 2294/Unit Mode of Attack: Dealloying
Boiler Feed Water Heat Exchanger DGA Steam Condensate (Shell-Side) E110 -D E110 -E E110 - F Steam Condensate Tanks D-102 A/B DGA Steam Condensate (Shell-Side) E110 -A E110 - B Dearator Feed Water (Tube-Side) To Dearators D-103 A/B/C E110 -C
Condensate Stripper Reboiler Type: Shell & Tube Service: Shell side: Sour Wet HC Tube side: Steam Shell Material: Carbon Steel Tube Material : Carbon Steel Mode of Attack: External Pitting/Fouling
Tube Bundle: External Fouling
Regen. Steam Condenser Type: Air Cooled Service: Steam Material: Carbon Steel Number of Tubes: 273/unit Mode of Attack: ?
Regen. Steam Cond. - Closed Header Box
Root Causes Mode of Operation Contaminants Metallurgical Design Corrosion Fouling Need For Corrosion Management program with Predictive & Preventive Strategies
Corrosion Management Strategies Enhance Monitoring: ¾ Video Borescoping ¾ Magnetic Flux Leakage (MFL) ¾ Internal Rotary Inspection System (IRIS) ¾ Laser Optic Tube Inspection System (LOTIS) ¾ Remote Field Eddy Current (RFEC) Explore suitable corrosion protection options: ¾ New Clad Fabrication Vs Strip lining of existing equipment, ¾ Use of tube inserts than retubing ¾ Thermal Sprayed Coatings , Coatings ¾ Corrosion Inhibition, VCI
Corrosion Management Strategies Monitor Process chemistry Establish Best Practice, Corrosion Control Manual Partner with CSD in Amine JIP ¾ Develop database ¾ Parametric evaluation of Temp, CO2/H2S ratio, HSAS, Organic Acids ¾ Develop software corrosion prediction tool (Predict-Amine) ¾ Expand R&D For Better Understanding of the New problems Partner with CSD/BPC in CAST Validation ¾ Prediction of corrosion and scaling tendencies in BFW ¾ Diagnose process stream chemistry variations
Integrity Management Programs Process Stream Monitoring Program Timely Evaluation of Monitoring Data Predictive and Preventive Corrosion Management Involvement in Design Phase Explore suitable Corrosion Protection Options Enhance Corrosion Monitoring Program System Upgrade Conduct Risk Based Assessment Conduct Fitness-For-Service MOC Implementation
Asset Integrity Management (AIM) Contributing Factors Operational Integrity ¾ Operating envelopes Methods ¾ Contaminants Inspection Design Integrity Technical Integrity ¾ Inspection ¾ Process ¾ Maintenance ¾ MOC Operation Maintenance Technology Design Verification Standards Reliability ¾ Technical function AIM Maintainability ¾ Verification/Review Availability ¾ Design Condition
Conclusions HE are critical Process Equipment and require periodic comprehensive integrity assessment. Identify Damage Mechanisms. Corrosion trend can be generic but can also be plant specific, which requires careful evaluation. Conventional NDE techniques have Limitations. Advanced NDE is crucial. Establish comprehensive process stream monitoring program Ensure an Active On-Stream Inspection Program Enhance Corrosion Monitoring Program Evaluate the Monitoring Data in coordination with other disciplines Partner with Other Organizations or JIP Implement the Integrity Management Program
Acknowledgements Process Eng Unit, UGP ME&CCD, Consulting Services Dept. M&CED, Consulting Services Dept PED, P&CSD R&D Center Inspection Technology Unit
Boiler Feed Water Heat Exchanger Dearator Feed Water (Tube-Side) DGA Steam Condensate (Shell-Side) Steam Condensate Tanks D-102 A/B To Dearators D-103 A/B/C E110 -A 10 - B E110 -C E110 -D E110 -E E110 - F DGA Steam Condensate (Shell-Side) Condensate Stripper Reboiler Type: Shell & Tube
About Corrosion 4 Parts of a Corrosion Cell Anode (location where corrosion takes place) o Oxidation Half-Reaction Cathode (no corrosion) o Reduction Half-Reaction Electrolyte (Soil, Water, Moisture, etc.) Electrical Connection between anode and cathode (wire, metal wall, etc.) Electrochemical corrosion can be
Technical Data Sheet Online Only 00816-0100-3045, Rev CA Corrosion and Its Effects May 2003 2 CORROSION BASICS Corrosion is the gradual destruction of a metal by chemical or electrochemical means. The most generic form of corrosion is galvanic corrosion. A combination of a cathode, an anode
1 Corrosion Overview: Internal Corrosion, External Corrosion and Cathodic Protection 2016 AGA/SPE Underground Storage Operators Workshop April 5, 2016
PURPOSE: The purpose of this experiment is to illustrate the principles and practical aspects of corrosion and corrosion prevention. LEARNING OBJECTIVES: By the end of this experiment, . corrosion-o2-production-FV.pdf Corrosion Prevention. There are a number of methods used to stop or slow down the spontaneous corrosion of iron. Barrier
Choose materials compatible with environment. Do not create corrosion cell through design/construction details. Corrosion Inhibitors Alter the environment adjacent to metal to passivate and protect metal. Concrete or mortar on steel are inhibitors Concepts of the Four Basic Methods Corrosion Control
Jan 22, 2015 · the atmosphere directly by some industries, accelerating the corrosion process on metals these substances en-counter. Atmospheric corrosion is ubiquitous and is responsible for more metal damage than any other form of environmental corrosion. 1.3. Sources of Corrosion There are several sources which
Table 4.10: Minideck B - ASTM G 109 Corrosion Rate ( A/cm2) Table 4.1 1 : Minideck B - ASTM G 109 Corrosion Potential (mV) Table 4.12: North Main Street Eastbound GECOR 6 Corrosion Rate ( A/cm2) Table 4.13: North Main Street Eastbound GECOR 6 Corrosion Potential (mV) Table 4.14: North
Corrosion Passivation 2H 2 O O 2 4H 4 e– H 2 2H 2 e– Fig. 1 C (77 F), show-ing the theoretical domains of corrosion, immunity, and passivation. Source: Ref 1 8 10 6 4 2 1.0 0.8 0.6 0.4 0.2 2 4 6 8 10 Days on test Corrosion rate, mils/yr 1 20 40 60 80 A B Fig. 2 Corrosion
