UNDETECTED AND SILENT LEAKS
TANKS AND LINERS Advancements to Eliminate Major Risks
PRESENTED BY CURTIS GOAD, CEF
UNDETECTED AND SILENT LEAKS TOPICS
Leaks and Failures Secondary Containment/ Enviro Reality
Leak Detection Advancements
Plastic Welds Conclusion
UNDETECTED AND SILENT LEAKS 2 QUESTION
A Leak is:
A. Always a serious problem D. Easily found
B. Always worsening E. Always repairable
C. Inevitable F. All of the above
None of the above
UNDETECTED AND SILENT LEAKS 3 BASIC CONSIDERATIONS
No “Silver Bullet” Material Exists
Concentrations
Chemicals Temperatures and Mixtures Operating Low, High & Exothermic
All Service Parameters Must Be Considered
UNDETECTED AND SILENT LEAKS 4 BASIC CONSIDERATIONS
No “Silver Bullet” Material Exists
Any containment is only as good as its weakest element
UNDETECTED AND SILENT LEAKS 5 BASIC CONSIDERATIONS
No “Silver Bullet” Material Exists “ Plating tanks should not “ have drain valves.
FRANK ALTMAYER, NASF INSTRUCTOR
UNDETECTED AND SILENT LEAKS 6 BASIC CONSIDERATIONS
No “Silver Bullet” Material Exists “ Poor welding is a common “ cause of lining failure.
PHILIP A. SCHWEITZER
p. 345 Corrosion of Linings and Coatings 2007
UNDETECTED AND SILENT LEAKS 7 BASIC CONSIDERATIONS
No “Silver Bullet” Material Exists
All coatings fail eventually – some
“ fail prematurely – many failures are costly – most failures“ are preventable.
MIKE O’BRIEN, NACE INSTRUCTOR
UNDETECTED AND SILENT LEAKS 8 AGA SURVEY NASF SURVEY (2016) (2009)
% of companies said tanks and linings % 30 have not advanced as expected 50
71 % have experienced tank leaks 80 %
% rate their leaks as a major % 67 cost or burden 50
% have experienced % 18 catastrophic failure 10
UNDETECTED AND SILENT LEAKS 9 SO WHAT IS THE CONVENTIONAL WISDOM AS IT APPLIES TO TANKS AND LINERS?
Tanks are Suppliers are Plastic tanks are Polypro tanks commodities plentiful and cost-effective are great easily replaced
Bonded PVC Drop-in bag Spark testing is linings have liners save “best practice” issues money
UNDETECTED AND SILENT LEAKS 10 SO WHAT IS THE CONVENTIONAL WISDOM AS IT APPLIES TO TANKS AND LINERS?
Tanks are Suppliers are Plastic tanks are Polypro tanks commodities plentiful and cost-effective are great easily replaced
BondedNOT PVC Drop-in bag Spark testing is linings have liners save “best practice” issues money
UNDETECTED AND SILENT LEAKS 11 36 % OF AGA 50 % OF NASF HAVE HAD A POLY TANK FIRE
Frequently used Polypropylene (PPL) plastic tanks have a maximum heat release rate approaching that of gasoline when burning!
Oil 42 to 46 PE/PPL 46
Natural Gas 52 PVC-U 8.4 to 18.5
Dry Wood 17 to 19 PVC-Soft 4.2 to 27.2
NoneNone havehave usedused Fire Retardant PPL tanks since the material is not fit for tank use
Source: Tanks and Tank Linings Survey conducted by Monitor Consultants LLC, Fall 2009
UNDETECTED AND SILENT LEAKS 12 “A BURNING MATERIAL WILL ONLY SPREAD A FIRE TO ADJACENT MATERIALS IF IT RELEASES SUFFICIENT HEAT TO IGNITE THIS MATERIAL”
Max RHR ,in kW/m2 Total Heat Released and 1600 maximum Rate of Heat 1400 1200 Release are extremely 1000 important when 800 determining fire hazards 600 400 200 0 LSPVC PVC-U PE PPL
PPL’s total heat released number is 14 times that of PVC!
From Ohio State University: rate of heat release calorimeter OSURHR, it is obvious that PVC is less likely to ignite other adjacent items than most other materials
UNDETECTED AND SILENT LEAKS 13 FLAMMABILITY & PVC/CPVC
PVC is among the least easily ignitable polymers
PVC is one of the least flammable polymeric materials and one of those with the lowest flame spread rate
PVC will not continue burning unless a large, continuous heat source is applied to it, nor will it readily spread flame
UNDETECTED AND SILENT LEAKS 14 OTHER DRAWBACKS OF POLYPRO TANKS
AGA SURVEY NASF SURVEY (2016) (2009)
% have had their plastic tanks % 54 damaged or cracked 60
% have experienced problems finding % 37 and fixing plastic tanks leaks 50
% have had to put a % 19 bag liner in a plastic tank 40
Source: Tanks and Tank Linings Survey conducted by Monitor Consultants LLC, Fall 2009 AGA (American Galvanizers Association), NASF (National Association For Service Finishing)
UNDETECTED AND SILENT LEAKS 15 COPOLY PPL MUCH HARDER TO WELD
Hitting the glove is much harder than hitting the strike zone
UNDETECTED AND SILENT LEAKS 16 DO BAG LINERS REALLY SAVE MONEY?
Poor fit and wrinkles create problems
Leaks may be difficult to find and repair
Liner may float and move into working area
May not allow for inspecting steel and weld integrity
May promote rust to form behind liner
UNDETECTED AND SILENT LEAKS 17 BONDED PVC LININGS HAVE ISSUES
Repairs requiring outside service
Disposal
Leaks from pinholes or weld failures Bond separation
Old linings that have started to leak or crack Pitfalls with AC high voltage spark testing
Source: Tanks and Tank Linings Survey conducted by Monitor Consultants LLC, Fall 2009
UNDETECTED AND SILENT LEAKS 18 HAND WELDING PROBLEMS
Contaminated Weld
UNDETECTED AND SILENT LEAKS 19 “LET’S TRY SOMETHING NEW”
The alternative may survive the one year warranty, but then what?
UNDETECTED AND SILENT LEAKS 20 LEAK DETECTION
Spark Testing
. All plastic welds should be spark tested
. If plastic welds are over a non-conductive material, use graphite (carbon) or lead or aluminum tape behind welds, to allow for spark testing
. Caution! Ac (plug-in) spark testing can do damage
. DC spark testers (battery operated and requiring a ground) are safer, more efficient and effective
UNDETECTED AND SILENT LEAKS 21 LEAK DETECTION
Electrical Conduction
. Periodic full tank (or sump) leak checking via current flow
. Measures permeation
. An aggregate reading
. Simple and more sensitive than DC spark testing
UNDETECTED AND SILENT LEAKS 22 LEAK DETECTION
Tanks/Secondary Containment
. Visual – weep holes . Ultrasonic detection (using sound waves) . Volumetric . Chemical – Single: HF, HCL and H2S or Multiple . Ground water monitoring – best if product floats → requires wells . Tracers / Markers / Scent . Vapor monitoring – . Dye/Smoke injection best if product evaporates → requires wells . Hydrogen gas . Noise – finely tuned microphones, turbulent flow
Piping
. Line tightness testing (Hydrotest) . Boroscopes (video cameras) . Automatic line leak detectors – . Infrared radiometric for pressurized lines
UNDETECTED AND SILENT LEAKS 23 DESIGN TIPS
Try to Avoid Tanks want to be round
. Wet Pits Is that possible??? If so, it saves $$$ . Double Walls with one bottom . Rectangular Sumps Less Structure . Unnecessary Penetrations
. Overloading Rims
. Divider Walls
. Buried Pipes
Fewer Welds
UNDETECTED AND SILENT LEAKS 24 PLASTIC WELDS AND WELDING
Skill and Experience are Critical! All welding must be continuous, leak/pinhole free and mechanically strong
Highest Welding Machines Strength Dielectric Bending Butt-Welding Electrofusion (Radio Frequency) Only with
“machines can we guarantee “ Extrusion Welding Machines Fully melting the A single pass ( no heating welding rod results in Faster and less sensitive quality of welds. & cooling cycling as with a homogeneous weld to oxidation multiple pass welds) with fewer stresses DR. ING MICHAEL GEHDE, GERMAN MACHINE BUILDER
Least “Hand” Welds (including seam strip) – Hot Air Strength
The fewer the better – both linear feet and number of passes
UNDETECTED AND SILENT LEAKS 25 MANY PLASTIC SHOPS HAVE QUALITY ASSURANCE (Q.A.) PROGRAMS
Formal plastic Routine testing as specified welder training AWS b2.4 standard specification for welding
Qualified welders based Qualified plastic on above standard welding inspectors
Courtesy of Gary Hopkins, Plastek Werks, Inc.
UNDETECTED AND SILENT LEAKS 26 WHAT ABOUT SHOPS WITHOUT TRAINING, TESTING AND QUALIFICATION PROCEDURES?
A flawed plastic weld can result in
Environmental Pollution Costly Repair
Health and Safety Issues Product Failure
Litigation Costly Downtime
Courtesy of Gary Hopkins, Plastek Werks, Inc.
UNDETECTED AND SILENT LEAKS 27 MAJOR FACTORS FOUND IN PLASTIC WELD FLAWS
Untrained/Unqualified Welders Site Conditions
Improper & Poorly Maintained Weld Speed Welding Equipment
Improper Melt Temperature Filler Materials Not Compatible With Parent Materials
Improper Pressure Poor Workmanship
Lack of Weld Penetration Contamination
Courtesy of Gary Hopkins, Plastek Werks, Inc.
UNDETECTED AND SILENT LEAKS 28 Lack of Fusion (incomplete fusion), Extrusion Weld, AWS G1.10M, Annex IV, Flaw #4011
Courtesy of Gary Hopkins, Plastek Werks, Inc.
UNDETECTED AND SILENT LEAKS 29 AWS B2.4: PLASTIC WELDER AND WELDING PROCEDURE AND PERFORMANCE QUALIFICATIONS
Written examination
Weldment(s) per qualified Welding Procedure Specification (WPS) . Horizontal . Vertical . Other, if required
Examine/test weldments and document results
If acceptable, approve Performance Qualification Test Record (PQTR)
AWS B2.4 referenced within ASME standards
UNDETECTED AND SILENT LEAKS 30 SECONDARY CONTAINMENT DECISION PROCESS
110% (State) or 100% (Federal)
*Courtesy of Temple University
UNDETECTED AND SILENT LEAKS 31 Secondary Containment Requirements
. All liquid hazardous materials must be in approved secondary containment to prevent release and uncontrolled: – Mixing of incompatible chemicals – Discharge of hazardous materials through unplugged drains, cups sinks, storm drains, sewers, etc. – Damage associated with liquid materials leaking through tile and concrete floors to workplaces below . All liquid hazardous materials must be in approved secondary containment whenever stored on a floor . All hazardous materials must be in approved secondary containment whenever it has been declared a waste . Hazardous materials stored in non-approved or sub-standard storage cabinets or units that may pose an additional risk (flammables or oxidizers in wood cabinets) must be placed in secondary containment until an approved storage unit is installed . Secondary containment is required whenever specified by a federal, state or local regulation
Containment Volume
. Secondary containment for a single container will be 110% (State) or 100% (Federal) of the primary container . Secondary containment for multiple containers will be 150% of the largest containers volume or 10% of the aggregate volumes of all the containers, whichever is greater
Containment Construction
. Secondary containment must be compatible with the stored materials and be constructed of materials capable of containing a spill or leak
*Courtesy of Temple University
UNDETECTED AND SILENT LEAKS 32 RISKS
Catastrophic Failure . May overwhelm Secondary Containment
Bowing/Deflection CATASTROPHIC FAILURE “Hidden” Damage
Liability
Contaminated Soil or Ground Water
UNDETECTED AND SILENT LEAKS 33 EPA SETTLEMENTS
Chrome Facility Army Base
Pennsylvania hazardous Alabama must address waste lagoon estimated cost 19 million cubic yards of contaminated $4.5 million soil and/or ground water
Consent Decree (NRDC vs EPA) RCRA Classification
Storing hazardous waste for a Reducing risk of period longer than permitted. accidental releases $1.5 million (2017-2019) violation fine plus 2 years Federal probation
Ethan Ware, Attorney – WilliamsMullin.com
UNDETECTED AND SILENT LEAKS 34 EPA 2015 ENFORCEMENT “ACCOMPLISHMENTS”
$7 BILLION in investments and clean up
$404 MILLION in penalties and criminal fines
in projects from criminal $4 BILLION prosecutions 129 COMBINED YEARS OF $1.975 BILLION for superfund sites incarceration for sentenced
for environmental mitigation DEFENDANTS $39 MILLION projects for local communities
$13.4 BILLION Total
UNDETECTED AND SILENT LEAKS 35 ADVANCEMENTS To Minimize Risks
UNDETECTED AND SILENT LEAKS 36 INFUSED MACHINE WELDS
Full Corner Penetration
. No voids behind the sheet . No channels for solution to flow through
UNDETECTED AND SILENT LEAKS 37 ELIMINATE (OR MINIMIZE) SEAM STRIP (HAND) WELDING
Gap
No Gaps! Full Weld Penetration
UNDETECTED AND SILENT LEAKS 38 MOLDED CORNER INSERTS
UNDETECTED AND SILENT LEAKS 39 RIGID PVC & CPVC OPTIONS & CORNER COMPRESSION TESTING
Even under extreme loads
Weld hasn’t failed!
UNDETECTED AND SILENT LEAKS 40 DESTRUCTIVE COMPRESSION TESTING OF MACHINE WELDED PPL
1 2 3
Click here to view full video
UNDETECTED AND SILENT LEAKS 41 DESTRUCTIVE COMPRESSION TESTING OF MACHINE WELDED CPVC
1 2 3
Click here to view full video
UNDETECTED AND SILENT LEAKS 42 FULL WALL (OR LARGE) RADIO FREQUENCY WELDED PANELS
UNDETECTED AND SILENT LEAKS 43 OVERLAP EXTRUSION WELDS FOR VERY LARGE TANKS
UNDETECTED AND SILENT LEAKS 44 CLEAR PVC PROTECTS YET IS SEE-THROUGH
PPL Tank with Steel Structure and Insulation Coated Carbon Steel Lined Tank
UNDETECTED AND SILENT LEAKS 45 ANCHORED WELDING TECHNOLOGY
UNDETECTED AND SILENT LEAKS 46 PERIMETER ANCHORED LININGS
Perimeter welds mechanically anchor the lining to the tank
Can be both dropped in and field installed
No surface preparation is required
Old tank can be refurbished with new lining/warranty
Failed linings overlaid without costly removal
UNDETECTED AND SILENT LEAKS 47 UNDETECTED AND SILENT LEAKS 48 UNDETECTED AND SILENT LEAKS 49 1 2 3
Click here to view full video
UNDETECTED AND SILENT LEAKS 50 BAG LINER
1 2 3
Click here to view full video
UNDETECTED AND SILENT LEAKS 51 TYPE I VS. TYPE II PVC FOR TANK BUMPERS
1 2 3
Click here to view full video
UNDETECTED AND SILENT LEAKS 52 TYPE II PVC FOR BUMPERS
1 2 3
Click here to view full video
UNDETECTED AND SILENT LEAKS 53 DOUBLE TANK SYSTEM
Inner & outer tanks have water in the interstitial space under the inner tank for . Full tank electrical conduction leak detection
No bypass shorts
Water mitigates leak damage
Similar to Gas Station UST* Secondary Containment
*Underground Storage Tank
UNDETECTED AND SILENT LEAKS 54 TOTAL COSTS ANALYSIS
REPAIR or LOST TOTAL INITIAL MAINTENANCE YEARS of RELINING DOWNTIME PRODUCTION SQUARE FEET PRICE COST SERVICE LIFE COST OF COST (PROFITS) OWNERSHIP
80 Square Feet Tank (4’ x 4’ x 4’ deep, ID’s) “A”
IP MC RC D LP SF YEARS TCO $5,000 $500 $800 $600 $900 80 5 $19.50
$7,800 400 $19.50 “B”
IP MC RC D LP SF YEARS TCO $10,000 $800 $0 $0 $0 80 10 $13.50
$10,800 800 $13.50
“B” IS DOUBLE THE INITIAL PRICE YET SAVES 30% ON T.C.O. BY USING THIS FORMULA WE CAN COMPARE AMONG MATERIAL CHOICES
UNDETECTED AND SILENT LEAKS 55 CONCLUSION
Stay Informed
Insist on Responsible and Qualified Bidders (Plastic Welding AWS B2:4)
Leverage Advancements
Eliminate Major Risks
UNDETECTED AND SILENT LEAKS 56 APPENDIX Additional Slides That May Be Helpful
UNDETECTED AND SILENT LEAKS 57 TIPS
Steel Lined Tanks
. Store filled with salt water . If stored for an extended time inspect before putting into service . No steel welding or torch cutting allowed, as can damage interior lining
Plastic Tanks
. Be extremely careful with forks on lift trucks . Never drop or impact the tank . Is there adequate reinforcement? Rim load support? . Always fully support the entire tank bottom . Understand temperature expansion and contraction . Store tanks inside, out of direct sunlight and above 32°F
Leaching
. The safe practice is to leach new tanks or linings before filling with process solution . May not be required with all materials . May be a cost to avoid if one can safely do so
UNDETECTED AND SILENT LEAKS 58 TANK USERS DESERVE...
QUALITY MATERIALS
A FUNCTIONING SUPPLIER EXPERIENCED/TRAINED/SKILLED/TESTED QA/QC Program WELDERS OR APPLICATORS INSURANCE/REFERENCES/TECHNICAL SUPPORT SAFETY CERTIFIED/DRUG AND ALCOHOL FREE The Right to Inspect – both WARRANTIES DURING FABRICATION and ON TESTING before shipment LICENSED OR APPROVED, IF APPLICABLE
. NEUTRALIZED, CLEAN AND DRY TANK TO WORK IN WHEN CLEANING, WILL LIVE STEAM OR SOLVENTS DAMAGE THE LINING? SUPPLIER . DISPOSAL OF OLD LININGS BY OWNER EXPECTATIONS . NO TRAVEL OF HOISTS OR PARTS OVER TANK . A SAFE JOBSITE ON FIELD WORK CONFINED SPACE and LOCKOUT/TAGOUT . ADEQUATE POWER AND WATER (IF NEEDED)
UNDETECTED AND SILENT LEAKS 59 SAFETY TIPS AND TANKS
LEAVE SPILLS FOR CLEANUP LATER. CLEAN UP PROPERLY PLANK TANKS BEFORE DON’T SPILLS IMMEDIATELY – BEFORE AN ACCIDENT DO WORKING OVERHEAD RESULTS
ENGAGE IN HORSE-PLAY AROUND TANKS. DON’T A SPLASH OR TRIP COULD GIVE YOU A BAD MAKE SURE THAT A PROPERLY FUNCTIONING CHEMICAL BURN SELF-CONTAINED BREATHING APPARATUS, DO AND AN OPERATOR TRAINED IN ITS USE, IS AVAILABLE FOR EMERGENCY RESCUE CLIMB OUT OVER, LEAN OVER OR WALK ON DON’T TANK RIMS OR ANODES RODS – SLIPPING INTO A TANK IS A LEADING CAUSE OF VERY SERIOUS INJURIES
MAKE CERTAIN THAT ALL EQUIPMENT IS DO PROPERLY LOCKED OUT / TAGGED OUT CLIMB INTO A TANK, OR ENTER A CONFINED BEFORE WORKING SPACE, WITHOUT EMPLOYING THE BUDDY DON’T SYSTEM, ENSUING PROPER VENTILATION, AND FULLY COMPLYING WITH YOUR PLANT’S “CONFINED SPACE RULES”
EVER LIFT A BAG OR DRUM OF CHEMICALS INSPECT TANKS AND PIPING FOR LEAKS AND DON’T ABOVE THE TANK RIM. THE WHOLE CONTENTS DO CORROSION AND DEFLECTION (BOWING) COULD FALL IN, CAUSING A “BLOWUP”
UNDETECTED AND SILENT LEAKS 60 MAINTENANCE
Upkeep – Inspection – Record Keeping – Condition Monitoring – “Preventive”/”Pre-Emptive”
Leaks? Drips? – If tanks must have DRAIN VALVES they should be CHECKED DAILY!
Steel Tank Exterior
. Drip shields working? Rusting? Weld areas? Edges . Bowing/structural stability . Visual inspection (number of rust spots per square foot) . Solution puddling on girths or structure
Plastic Tanks – Exterior
. Bowing/structural stability . Damaged girthing . If encapsulated steel structure, look for “hidden” . Stress cracking corrosion – spark test encapsulation
UNDETECTED AND SILENT LEAKS 61 MAINTENANCE (CONTINUED)
Interior Linings
. Cuts or gouges . Chemicals coming back into tank from behind lining . Loose seams . Excessive parts in tank bottom . Cracking/“alligatoring”? Pay close attention to solution to air interface . Plating “trees” . Blistering
Plastic Tanks – Interior
. Stress cracking, especially at welds . Buckling/deformation . Note: a 30 foot long tank at 180°F – Pvdf and pp ≈ 3” expansion – Cpvc and pvc < 1.5” expansion
UNDETECTED AND SILENT LEAKS 62 REPAIRS
Can you do your own maintenance and repair?
Can the tank be sent to the FAB shop for repair or relining?
Can you perform or subcontract prep work locally to reduce field time and charges from the specialty contractor?
. Steel repair? . Priming? . Stripping old lining? . Dehumidification, Scaffolding? . Blasting? . Confined space – provide hole watch person?
Lined PVC Tanks . Small exterior coating defects should be “spot repaired” early and easily . Lining leaks or pinholes should be repaired as soon as possible . Strip welds cannot be repaired by reheating the weld and exerting pressure on the strip . A faulty weld (burned or cold welds) must be cut out, cleaned and re-welded . Do not burn or blister the sheet or the strip . A good strip weld should reveal flow lines along both sides of the welded strip. If not apparent, try to pry the strip loose from the sheet with a knife
UNDETECTED AND SILENT LEAKS 63