Presentation on theme: "Trends with Shop-Fabricated Storage Tanks"— Presentation transcript:
1Trends with Shop-Fabricated Storage Tanks Wayne GeyerSteel Tank InstituteNovember 18, 2013
2Who 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 productsSTI members account for nearly all of the total shop fabricated underground steel storage tank production capacity in North America
32012 Annual Product Awards: Steel Fabricated Products Driving traffic to our website, promoting steel and sustainability.Please take a look!Any questions?Thank you for this opportunity to share our efforts with you.
5What does the Steel Tank Institute do? UST and AST tank technologiesIndustry standards and recommended practicesLicense manufacturers to build tanks to STI specificationsQuality controlInformation resourceCertification4 – 50,000 Gallon Permatanks Installed at Northwestern Univeristy
6STI Tank RegistrationEvery tank built with an STI labeled is inspected by tank fabricator to meet STI specificationTank is “registered” with STISTI maintains database with over 400,000 entries
7Tank Performance Evaluation All STI labeled UST’s subject to 3rd party warrantySTICO Mutual has strong claims management programSTI gets feedback on quality and performance
9STI Certification Programs 927 Certified SP001 Aboveground Storage Tank Inspectors484 Certified Cathodic Protection TestersOver 130,000 sti-P3 tanks tested for cathodic protection through WatchDog programNEW: On Line Learning ProgramT*I*M Tank Integrity Management
10STI Shop-Fabricated Tank Programs > 100 tank shops licensed and inspected14 tank fabrication standards19 recommended practices for testing, installation and inspectionNEW: R111 Storage Tank MaintenanceUnder Development: SP131- UST Inspection, Repair, & Modification
13Underground Storage Tanks Primarily used at service stations todayTanks are getting largerSTI DatabaseAverage capacity in 2013 for jacketed tank exceeds 15,000 gallons25 years ago, the typical UST at a service station was 8000 – 10,000 gallons
14Compartment TanksCompartment tanks have become very common for both UST’s and AST’sMultiple fuel types can be stored within one tank unitProvides user/owner versatility as more fuels develop
15Underground Storage Tanks UL 58 is the principle standard for steel tank construction – single wall and double wall steelUL 1746 is the principle standard for corrosion control and for jacketed (non-metallic outer wall) tank construction
16Underground Storage Tanks Regulations require all tanks incorporate secondary containmentToday, jacketed tanks are favored by many buyers as outer containment provides a corrosion barrier and secondary containmentOther corrosion systems use two walls of steel
17Fabricating 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.
18Testing 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
19Production 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.
20Preparing 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.
21Interstitial VacuumAfter the vacuum is applied, the tank is held in storage until it is made ready for deliveryThe 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.
22Tank Compatibility - Biofuels E10, E15, E85, B2, B20, B100Steel Tank Manufacturer Certification StatementsSTI Web SitePerformanceTanks are Cleaner – SludgeBiodiesel Shelf LifeWater ConcernsPhase Separation - Ethanol
23Recent Events Biofuels SumpsEPA ORD ResearchNIST ResearchPublications“Compatibility of UST Systems with Biofuels,”Published by ASTSWMOCase StudiesResearch and Work GroupsUnderground tanks storing E85
24Ultra Low Sulfur Diesel Issues Corrosion of metal components within FRP tanks storing ULSDClean Diesel Fuel Alliance supported research from Battelle Labs - completed in 2012Further studies under considerationSTI ResearchTanknology hired to visually examine the insides of steel and FRP ULSD tanksFuel samples extracted and testedExample – Las Vegas service station tanks under same ownerFRP tank vapor control fitting – top right photoSteel tank vapor control fitting – bottom right photo
28Aboveground Storage Tanks Most popular choice for shop-fabricated tanks for:Fleet motor vehicle fueling applicationsFuel for emergency power generatorsBulk oil and chemical storageSecondary containment
29Aboveground 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.
30Aboveground Storage Tanks Secondary contained shop-fabricated steel tanks are preferred:Serves as spill control to meet fire codesMeets SPCC rules with proper use of overfill prevention equipmentDouble wall construction preferred over diking
32Protected AST’s Protected aboveground tanks preferred when: Installed in close proximity to buildings & property linesDispenser mounted on tankMinimize fire safety hazardsMeet codes for motor vehicle fuel dispensing
33SPCC – AST InspectionsEPA references STI SP001 standard for smaller tank inspection and integrity verificationCategory 1 preferredDouble wall tanks can be easily tested with vacuum to prove containment integrityCategory 3 – Higher Risk to Environment
34Facilities with a mix of tanks require one type of inspector
35Release Prevention Barrier (RPB) Liquid containment barrierUnder the ASTDiverts leaks toward the perimeter of the AST where they can be easily detected