Presentation on theme: "Wayne Geyer Steel Tank Institute November 18, 2013."— Presentation transcript:
Wayne Geyer Steel Tank Institute November 18, 2013
Who and What is STI/SPFA? Association of 180 fabricating and affiliate companies of steel construction products – shop-fab tanks, field erect tanks, pipe, pressure vessels and other special fabricated products STI members account for nearly all of the total shop fabricated underground steel storage tank production capacity in North America
What does the Steel Tank Institute do? UST and AST tank technologies Industry standards and recommended practices License manufacturers to build tanks to STI specifications Quality control Information resource Certification 4 – 50,000 Gallon Permatanks Installed at Northwestern Univeristy
STI Tank Registration Every tank built with an STI labeled is inspected by tank fabricator to meet STI specification Tank is registered with STI STI maintains database with over 400,000 entries
Tank Performance Evaluation All STI labeled USTs subject to 3 rd party warranty STICO Mutual has strong claims management program STI gets feedback on quality and performance
Education, Research, & Advocacy
STI Certification Programs 927 Certified SP001 Aboveground Storage Tank Inspectors 484 Certified Cathodic Protection Testers Over 130,000 sti-P3 tanks tested for cathodic protection through WatchDog program NEW: On Line Learning Program T*I*M Tank Integrity Management
STI Shop-Fabricated Tank Programs > 100 tank shops licensed and inspected 14 tank fabrication standards 19 recommended practices for testing, installation and inspection – NEW: R111 Storage Tank Maintenance – Under Development: SP131 - UST Inspection, Repair, & Modification
Years in Number after 1970
Coatings Provide Corrosion Protection
Underground Storage Tanks Primarily used at service stations today Tanks are getting larger STI Database Average capacity in 2013 for jacketed tank exceeds 15,000 gallons 25 years ago, the typical UST at a service station was 8000 – 10,000 gallons
Compartment Tanks Compartment tanks have become very common for both USTs and ASTs Multiple fuel types can be stored within one tank unit Provides user/owner versatility as more fuels develop
Underground Storage Tanks UL 58 is the principle standard for steel tank construction – single wall and double wall steel UL 1746 is the principle standard for corrosion control and for jacketed (non-metallic outer wall) tank construction
Underground Storage Tanks Regulations require all tanks incorporate secondary containment Today, jacketed tanks are favored by many buyers as outer containment provides a corrosion barrier and secondary containment Other corrosion systems use two walls of steel
Fabricating Steel Secondary Containment After the primary tank is built and tested, the outer wall is fabricated atop the primary tank. The second wall is intimately wrapped atop the primary tank wall.
Testing the Interstice Most fabricators will test the interstice by bleeding air from a 3-5 psi pressurized inner tank into the secondary tank. The volume of the interstice is very small and can get pressurized rapidly. Access to the interstice can be fabricated in different ways
Production Test to Verify Both Walls are Tight Upon completion of production testing of the interstice with positive air pressure, and soap testing the welds of the secondary containment, all air is released. Then a vacuum is pulled within the interstice and monitored by the fabricator for tightness over time.
Preparing the Tank for Delivery After ancillary equipment installed, coatings applied, etc. the tank is made ready for shipment. Fabricators apply a vacuum into the interstice of secondary containment tanks.
Interstitial Vacuum After the vacuum is applied, the tank is held in storage until it is made ready for delivery The vacuum remains on the tank during storage, delivery, and during much of the installation. An easy view of the vacuum gauge to verify retention of the vacuum assures that both walls remain tight.
Tank Compatibility - Biofuels E10, E15, E85, B2, B20, B100 Steel Tank Manufacturer Certification Statements STI Web Site Performance Tanks are Cleaner – Sludge Biodiesel Shelf Life Water Concerns Phase Separation - Ethanol
Recent Events Biofuels 23 Sumps EPA ORD Research NIST Research Publications Compatibility of UST Systems with Biofuels, Published by ASTSWMO Case Studies Research and Work Groups Underground tanks storing E85
Ultra Low Sulfur Diesel Issues 24 Corrosion of metal components within FRP tanks storing ULSD Clean Diesel Fuel Alliance supported research from Battelle Labs - completed in 2012 Further studies under consideration STI Research Tanknology hired to visually examine the insides of steel and FRP ULSD tanks Fuel samples extracted and tested Example – Las Vegas service station tanks under same owner FRP tank vapor control fitting – top right photo Steel tank vapor control fitting – bottom right photo
Inspection and Maintenance of the Tank System
Inspection and Maintenance STI R111 Storage Tank Maintenance STI SP001 AST Inspection
Aboveground Storage Tanks Most popular choice for shop-fabricated tanks for: Fleet motor vehicle fueling applications Fuel for emergency power generators Bulk oil and chemical storage Secondary containment
Aboveground Storage Tanks UL 142 is the principle standard for steel tank construction – single wall and double wall steel. UL 2085 is the principle standard for two hour fire protected tank construction.
Aboveground Storage Tanks Secondary contained shop-fabricated steel tanks are preferred: Serves as spill control to meet fire codes Meets SPCC rules with proper use of overfill prevention equipment Double wall construction preferred over diking
31 ASTs with 2-Hr Fire Test Ratings
Protected ASTs Protected aboveground tanks preferred when: Installed in close proximity to buildings & property lines Dispenser mounted on tank Minimize fire safety hazards Meet codes for motor vehicle fuel dispensing
SPCC – AST Inspections EPA references STI SP001 standard for smaller tank inspection and integrity verification Category 1 preferred Double wall tanks can be easily tested with vacuum to prove containment integrity Category 3 – Higher Risk to Environment
Facilities with a mix of tanks require one type of inspector
Release Prevention Barrier (RPB) Liquid containment barrier Under the AST Diverts leaks toward the perimeter of the AST where they can be easily detected
Risk Matrix Concept – SP001 Tank SizeCategory 1Category 2Category 3 Shop built tanks PPP, E&L(10) ,000 PP, E&L(10)[P, E&L(5), I(10)] or [P, E(5) & L(2)] 5, ,000 P, E(20)[P, E(10)& I(20)] or [P, E(5) & L(10)] [P, E&L(5), I(10)] or [P, E(5) & L(1)] 30, ,000 P, E(20)P, E&L(5), I(15)P, E&L(5), I(10) Field erectedP, E(5), I(10) Portable containers PPP ** More Risk
Category 1 – Secondary Containment and CRDM Double-wall Tank Tank in a with Overfill Prevention Concrete Dike