Download - FRP Vessels and Piping in Chemical Processes
FRP Vessels and Piping in
Chemical Processes
Michael P. [email protected]
NACE Coating Inspector Level 3 #50795
Richard Taraborelli [email protected]
RT Consultants NACE Conference: March 18, 2015
• Comparison of FRP to alternatives in the chlorine and sulfur rich chemical environments.
• Case Studies with FRP lined steel and dual laminate construction.
• Improvements in technology and cost economics.
• The value of knowing what you are receiving.
Table of Contents
“You can expect what you inspect- nothing more.”
- John H. Mallinson
• You must know what you require and know how to identify it. Quality Inspections are needed.
Let the Results Speak for Themselves
• FRP has a distinct advantage handling these two elements and compounds.
• Awareness of the importance of material selection for application.
Two Scenarios: Chlorine and Sulfur
• Taking Brine and separating NaCl to make caustic and chlorine.
• Considered the harshest environment for corrosion and chemical attack.
• Have greatest needs for protection from harsh chemicals.
Background of Chloro-Alkali Plants
Electrolysis of NaCl or KCl:
2 NaCl + 2 H2O → 2 NaOH + H2 + Cl2
Chlorine reaction with water
Cl2 + H2O → HCl + HOCl (*NaOCl)
Trace of chlorate is formed:
2 HOCl + ClO-→ ClO3- + 2 Cl- + 2 H+
Some plants may produce HCl:
H2 + Cl2 → 2 HCl
Chloro-Alkali Processes
• Planning/Design/Development
• Purchase/Installation
• Maintenance/Repair
• Inspections
• Downtime/Lost Business Cost
Comparing Alternate Solutions
Chemical Environment Vulnerabilities
Chlorine/Halogens Sulfur/Sulfur Compounds
• Permeation and diffusion.
• Aggressive ion exchange (valence number).
• Lots of vulnerable compounds.
• Used to make many composites/elastomers
• Hardening and brittle effect on steel/rubber (N/L steel, cross-linkage).
• Permeation and diffusion.
• Localized chemical attack.
•
The Typical Composite
Filament Winding or Laminate (Ex. Pipe, Tank, Ducting, etc.)
Interior
Corrosion FRP Barrier
Veil andMat layer
Exterior
Structural FRP (Provides the Strength)
Different ratios of resin/glass depending on design
• Most substitution of materials is between the two choices.
• Each material has its own area of superior performance.
• Mainly compared from a lining standpoint.
Apples to Apples: FRP to Rubber
Stainless Steel 316L in Chlorine Service after 2 years
*Severe Pitting and Cracking
Materials Sulphuric Acid Hydrochloric
Acid Acid Chloride
Salts
FRP (epoxy vinyl ester resin)
100ºC to 30% 80ºC to 15% 100ºC all
concentrations
ChlorobutylRubber lining 80°C to 20% 79°C to 15%
52°C for sea water
Stainless Steel 316L 30 ºC to 5% Will Rust outWill Rust out above 60°C
Chemical Resistance
Halogens/Sulfur
Rubber TechnologyHandbook Reference
Rubber not recommended for chlorine.
Comparison between Rubber and FRP lined equipment
FRP Lining
Good with Silica Carbide
Rubber Lining
Excellent Wear Resistance
(dependent on hardness
and size of particles)
Chemical Resistance
Permeation resistance
Installed Cost
Life cycle maintenance and
cost
Excellent
Excellent
$100,000
+15 years**
Good
Fair/Poor
$80,000
3-6 Years* (NaClO)
*Data from White’s Handbook of Chlorination
Properties
** FRP life expectancy dependent on curing formulation
Repairing Rubber to FRP
Rubber Linings
• Labor intensive
• Repair is deficient to original
• Bonding Issues
• Longevity Issues
Fiber Reinforced Polymers
• Easy to repair with qualified workers
• Repair is close to original (depends on location)
• Can be reused and relined
Dual Laminate FRP Tanks w/ CPVC Liner
Steel Tanks Internally Lined w/ FRP
Resin: Epoxy Novolac Resin for Tanks &
EN Formulated Steel Lining Systems
Case Study: Spent Sulfuric Acid Tanks
@ Max Temp = 140F
Lining Life = 10 - 15 yrs.
Recommend 5-yr. inspect intervals
Environment:
Up to 80% Sulfuric Acid w/ Dissolved Cl2
Design Expectorations:
Case Study: Spent Sulfuric Acid Service
•
•11.
Storage Tank in 36% phosphoric acid
Temp= Ambient
Age = 35+ years
Pulp/Paper Manufacturing
Design Expectorations:
Case Study: Phosphoric Acid Used in Water Treatment
Still in Service
FRP Distinct Environment Advantages
Scrubber Vessels
Piping for
chlorine/acids/caustic
Stack Liners
Brine piping and tanks
Chemical titration and mixing
Hydrocarbon and sulfur/halogen
compound storage
Rubber Distinct Environment
Advantages
Transporting Containers
Railcar linings
Abrasive slurries
Steel pickling
Vacuum service
Dual Laminate FRP
Stand alone Construction
Take steel or concrete
out of the equation.
Longer service life in
corrosive environment
and service.
Dual Laminates Considerations
Selection Parameters
Compatibility
Alkalinity
Permeation
Design Temperature
Complexity/Geometry
Fabricator Expertise
Service Life Expectations
Availability
Lining Materials Used
PVDF Homopolymer
PVDF Copolymers
ECTFE Homopolymer
ECTFE Copolymer
ETFE
MFA
FEP
PFA
PTFE not common...
Modularization of Large
Construction of FRP
Scrubber assembly for desulfurization
Inlet for Seawater
Case History: Flue Gas Towers
Location: Power Plant in Bełchatów
Service ConditionsChemicals: SO2,SO3, NOx, H2S
Dimensions: 34 meters long x 7.6 meters wide(One Section)
Exceptional Performance in sulfur rich conditions.
Oblation Technology
• Developed in streamlining FRP construction of larger objects.
• Can be engineered to withstand elements and comply with ASME Section X.
• Very Fast fabrication time= Labor Savings.
Tank Bottom Installation
Modularization for FRP= Oblation System
50 ft diameter, 40 ft high tank. Assembled in less than two months.
36% Concentration HCl Tanks
Large Stacks and Tanks
Sulfur Rich Exhaust
What Price Offers
Service Life
10 years Life
15 years Life
30 years+
Service Rating
Oilfield Service
ChemicalService/Treatment
ASME RTP-1 Tanks
Cost to Steel Ratio
1.2 Ratio 1.5 Ratio 2.0 Ratio
What Inspections Find
• Mechanical Abuse.
• Excessive Temperature.
• Chemical Attack
• Diffusion and Permeation
• Material Specifications
Elastomers Common Failures
Poor curing (initial)
Diffusion
Applied stress
Embrittlement
Micro-cracking
Swelling
Impact
Environmental cycling
Aging (Time)
Issues Affecting Laminate Performance
In the realistic world:
Lack of Fusion and Poor Fit
Nozzle Misalignment
Air Voids Defects
More Issues
Blisters Delamination from Substrate
Laminate CrackingStress FailureMatrix shrinkageDry Spots and bad cure
And More…
Compliance
• Drawings
• Design Specifications
• Materials (lot numbers)
• Ambient Conditions
• Standards (ASME RTP-1)
• Verify Quality Control
• Pass/Fail Criteria
Quality Assurance Through Inspections
FINAL INSPECTION
Documents Review
Non Conformance
Reports
Cutouts
Resin Cure
Peel Adhesion Test (picture)
Dimensions and thickness
Physical properties
Quality is What Will Last
It took a hammer with a crowbar to rip it off
• Proper Material Selection for Service
• Comprehensive and descriptive specifications
• Qualify experienced GRP manufacturer
• Quality assurance throughout the process
• Inspect, Inspect, Inspect…
Lessons Learned
Keys to a Successful Project
“You can expect what you inspect- nothing more.”
- John H. Mallinson
“I prefer a composite bike to a steel one. “
- Michael Yee