above ground storage tanks & tank base sealing. - least expensive to construct - for storing...
TRANSCRIPT
Above Ground Storage Tanks &Tank Base Sealing
- Least Expensive to construct- For storing “Low Vapour Pressure” Products ( below 2 psi. )
Fixed Roof Tanks
Tank Base Sealing Types of Tank
Floating Roof Tanks
Fixed Roof Tanks- Least Expensive to construct- For storing “Low Vapour Pressure” Products ( below 2 psi. )
- To prevent evaporation loss- More expensive to build and maintain
Tank Base Sealing Types of Tank
Fixed Roof Tanks- Least Expensive to construct- For storing “Low Vapour Pressure” Products ( below 2 psi. )
Floating Roof Tanks- To prevent evaporation loss- More expensive to build and maintain
Silos- Ash (Fly ash)- Used for Storing “dry” products- Variety of construction materials
Tank Base Sealing Types of Tank
Tank Base SealingTank Base Construction
Large Storage Tanks – Typical Construction
1. Trench preparation for perimeter wall
2. Reinforced concrete containment wall
3. First sections of tank wall positioned
2 3
1
2 3
Tank Base SealingTank Base Construction
Large Tanks
4. Liner installed when required
5. Sand – bitumen foundation laid
6. Tank base installed 4
5 6
Large Tanks
Tank Base SealingTank Base Construction
7. Walls constructed
8. Roof welded in place
9. Tank completion 7
8 98 9
Tank Base SealingTank Base Construction
Large Tanks
1. Foundations prepared
2. Base and plinths constructed
3. Tanks installed
Tank Base SealingTank Base Construction
Small Tanks
1
2 3
Tank Base SealingProblem Areas – Tank Base
Corrosion of tank wall and chine angle
Determination seal
Corrosion of tank base
Tank Base SealingProblem Areas – Tank Base
Conventional methods to seal
tank base
Tank Base SealingProblem Areas – Tank Base
Asphalt & Bitumen
Mastics
Tank Base SealingProblem Areas – Tank Base
Bonded Rubber
Tank Base SealingProblem Areas – Tank Base
Steel Skirts
- Tank needs to be lifted up
Chine Angle
- Failure of Bitumen Seal
Corrosion at the Chine Angle
- Corrosion of wall / base / metal thinning- Contents to be emptied- Tank requires to be gas free – man entry- Sludge needs to be removed / disposed of
Tank Base SealingProblem Areas – Tank Base
Corrosion at the Chine Angle- Tank needs to be cut open for plate entry- New base needs to be built- Base welded into position- Hydro Test needs to be conductedApprox. Costs ( 90 foot tank )- $40,000 for cutting and entry / base removal- $8,000 for sand-bit floor screed replacement- $10,000 for flexible liner- $40,000 for new bottom plates- $100,000 for inspection and Hydro Test-------------- $198,000
Plus :- Tank cleaning / waste disposal costs- Tank out of service for 3 months
Tank Base SealingProblem Areas – Tank Base
Storage Tank Base Associated Problems
No grout or sealing measures Failed grout
Tank Base Sealing
Storage Tank Base Associated Problems
Failed grout Cracked Concrete Base
Tank Base Sealing
Tank Base Sealing
Conventional wisdom states: Replace failed system with more of
the same sealants Replace failed system with similar
sealants Switch sealing system to other
conventional sealing methods
PROVEN ^ LONG TERM, COST EFFECTIVE
SOLUTIONS ARE AVAILABLE
unconventional
Tank Base Sealing
Tank Base Sealing
Membrane systems for long term sealing of chine angle
Epoxy grouts for concrete ring repair and grout sealing
Urethane coatings for tank exterior
Tank Base SealingKey Features and Benefits
Weatherproof & Waterproof - Prevents ingress of water and provides long term corrosion protection
Seamless Encapsulant – Seals around irregular contours and is easily repaired if accidentally damaged
Tank Base SealingKey Features and Benefits
Maintains High Adhesion – Ensuring long service life
Flexible & UV Resistant – Long lasting and tolerant of movement through climatic variations unlike conventional sealants
Fire Resistant Systems Available
Tank Base SealingKey Features and Benefits
Durable & Tough – Long lasting and tolerant of industrial environments
Microporous – Allows trapped moisture to escape
Cold Applied – No hot work required ensuring safety in use where fire is a concern
Tank Inspection RequirementsAPI 653 ( American Petroleum Institute )
BS 2654 ( British Standard )
EEMUA 159 ( Engineering an Equipment Materials Users Association )
Requirement for all Tank users to Inspect and ensure integrity of their Structures
Frequency :1 Year visual / 5 Year integral
PA DEP 245 (Department of Environmental Protection)
Storage Tank Containment Issues
Before repair/coating After repair/coating
Tank Base Sealing
Maintain environmental compliance Maintain asset integrity Minimize headaches with
preventative maintenance
Questions?
Thank You for your time.