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How To Solve Corrosion, Sludge, & Fouling Problems in
ULSD Fuel Systems
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These Problems Lead To…
• Expensive, high maintenance
• Frequent replacement of equipment
• Slow pumping → Lost Business
• Pumps out of service → Lost Business
• Leaks
• Spills
6The Manager
• Dan JenkinsDan Jenkins: Some common myths about : Some common myths about ULSDULSD
• Bob TatnallBob Tatnall: What is different about : What is different about ULSD? What causes fouling, sludge and ULSD? What causes fouling, sludge and corrosion in ULSD?corrosion in ULSD?
• Tom FolkessonTom Folkesson: Where does fuel : Where does fuel polishing fit in?polishing fit in?
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Speakers and Subjects
• Stan SmithStan Smith: The pros and cons of tank : The pros and cons of tank cleaningcleaning
• Bob TatnallBob Tatnall: How do we : How do we stopstop fouling, fouling, sludge, and corrosion in ULSD sludge, and corrosion in ULSD systems?systems?
• DiscussionDiscussion
Some myths about ULSD
(“Truths” to follow later)
Myth 1: ULSD Fuel is ULSD Fuel is unstable,unstable, which which leads to sludge. Therefore, you should leads to sludge. Therefore, you should add stabilizers to your ULSD fuel to add stabilizers to your ULSD fuel to
prevent sludge formation.prevent sludge formation.
Myth 2: Algae Algae are a problem in are a problem in ULSDULSD
Myth 3: The more rapidly you turn your fuel over, the less sludge and
fouling there will be.
High Turnover Marketing Techniques High Turnover Marketing Techniques
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Quote from Fuel Dealer Advertisement
“All our fuels are filtered prior to leaving our bulk plant. With our fuels you're always assured of "Fresh Diesel Fuel" because of the rapid turnover of our products.”
Myth 4: I have my fuel polished and the contractor shows me clean fuel…..
Therefore my tanks are clean.
Myth 5: Biocides are the answer because, if I kill the Bugs, they can’t
cause problems.
Myth 6: If I useIf I use Detection Kits Detection Kits I can I can detect Microbes and Fungus Growth. Then detect Microbes and Fungus Growth. Then
I can add Biocides to kill them and the I can add Biocides to kill them and the problems will go away.problems will go away.
Myth 7: You can use an additive toYou can use an additive to remove all water remove all water from your tanks so from your tanks so bugs can’t grow and cause problems.bugs can’t grow and cause problems.
Bob Tatnall, P.E.
• For 30 yrs. – internal consultant at DuPont (equipment failures, corrosion, biocorrosion), group leader in biocorrosion research at DuPont
• Co-founder NACE committee on MIC• Published >40 papers and articles• Developed Fuel Right® treatment for #2 fuels to prevent sludge, fouling and corrosion in fuel systems
What is different about What is different about ULSD? ULSD?
What causes fouling, sludge What causes fouling, sludge and corrosion in ULSD?and corrosion in ULSD?
Each “generation” of #2 Fuel has unique properties and challenges
• Straight run distillate (prior to ’60’s) – excellent fuel but limited supply
• Cracked, high-sulfur #2 (’60’s-80’s) – unstable
• Low-Sulfur #2 (into 21st century) – excellent fuel, stable, air pollutant
• ULSD (since 2000) – excellent fuel, stable, low-pollution, poor lubricity, low conductivity
All generations of #2 fuel have certain common properties:
• They are mixtures of dozens – maybe hundreds – of different hydrocarbon molecules
• They contain paraffin and thus have cold-flow issues
• They support growth of certain bacteria, yeasts and molds when water is present
Regarding sludge, fouling and corrosion, the problem is not the fuel, but rather the “critters” that
grow in the fuel.
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Biofilms 101
Taken from: •“Simple methods for the investigation of the role of biofilms in corrosion” Bio-corrosion network, Brite-Euram III Thermatic Network
We store and transport fuels in open or vented containers. Because of this, nearly all fuels contain - water, and - microbes (“critters”)
WATER IN FUEL
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Water can be present in fuel as:
• Dissolved water (invisible, not a problem)
• Suspended water (emulsion or haze)
• Free water layer (in bottom of tank)
Emulsions or suspended water:
- Do not form in “pure” fuel
- Are formed by chemical surfactants
(from additives – or from microbes)
- Support growth of “critters”
- Can cause rusting of steel/cast iron
- Are usually (but not always) bad news
Microbes in #2 Fuel Microbes in #2 Fuel ……
1. Include bacteria and fungi
(yeasts, molds)
2. May come from the air, water, dirt and debris
3. Are always present in stored fuels
4. Cause problems, including sludge, fouling, and corrosion.
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The entire Supply Chain may be contaminated
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SLUDGE
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In Higher-Sulfur Fuels In Higher-Sulfur Fuels the Sludge was Black and “Slimy”the Sludge was Black and “Slimy”
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Classic, black sludge consists of: Classic, black sludge consists of:
• Water Water
• Degraded (solid) fuelDegraded (solid) fuel
• Trapped particles/debrisTrapped particles/debris
• Bacterial slimeBacterial slime
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Microbiologically Influenced Corrosion.
(MIC)
33Results Of MIC
Sludge and FoulingSludge and Fouling in ULSD may be in ULSD may be different – reddish instead of blackdifferent – reddish instead of black
First Signs are Slow Pump, Dispenser Issues First Signs are Slow Pump, Dispenser Issues and Need to Replace Filters Frequentlyand Need to Replace Filters Frequently
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Corrosion in ULSD SystemsCorrosion in ULSD Systems
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This Corrosion occurred in less than 18 months
How Long Does It Take for Corrosion to Occur?
• When Free Water is Present• When Sludge grows on metal surfaces
To Review: Corrosion Will Occur……
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The Battelle Report:
• Studied six underground ULSD tanks to attempt to understand corrosion occurring in those systems
• Concluded that the corrosion was probably caused by acetic acid generated by bacteria from ethanol contaminant in the fuel
• Did not provide “good science” due to inadequate funding.
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Questions So Far?
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“Captain” Tom Folkesson
Where does fuel polishing fit into this picture?
Fuel PolishingFuel PolishingCapt. Tom FolkessonCapt. Tom Folkesson
Oceanview Marine Services, LLCOceanview Marine Services, LLC
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Fuel Polishing
If you see this: Then you have this:
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Fuel PolishingFuel Polishing
Benefits:
a. Removes “Free Water”- this part is best value of
polishing.
b. Removes Loose “Debris”- Metal Sulphide-coffee
grounds, Aluminum Oxide-sandy grit, Common Dirt.
c. Removes Bottom Sludge- Asphaltene, bacterial slime.
d. Immediate Gratification- Pretty fuel samples.
e. Solves filter plugging issues “Today”!
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Fuel Polishing Fuel Polishing
Concerns:
1. Nothing More Than Industrial Filtration for loose particulate and water. Expensive filters, Disposal.
2. Does Not Address Suspended or Emulsified Water, nor acid value caused by bacteria waste.
3. Hard to reach area limited without expensive or dangerous access techniques .
4. Does not remove “Live” embedded bacteria in tank walls, fuel lines or pumps.
5. Bacteria re-growth never stops, even when Free Water is gone.
6. Not a long term solution.
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Stan Smith (“Smitty”)
• ’73-’88 - Owned Anthony Oil, Commercial Fuel Sales and Service
• “88-Present - Owns Atlantic Bulk Carriers, Delivers fuel, lubricants and water to ships; Removes “sludge” and disposes of or recycles; Operates No. Carolina to Maine
How About Tank Cleaning?
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Small tanks (≤ 2000 Gal.) Usually cleaned from outside.
(Difficult to do well.)
Larger tanks (≥ 5000 Gal.)Usually require manned entry.(Expensive, safety concerns.)
If scraped and shoveled only, cleaning is marginal, re-growth
of sludge is rapid.
High-pressure water blast is better – but expensive – and re-
growth is still fairly rapid.
Water Blast followed by Sand Blast is better yet – but even
more expensive – and tank is still not sterile so re-growth occurs
over time. (Also, sand blasting is destructive to tank walls.)
Regardless of method used, cleaning is not perfect, re-growth
occurs, and there is the added cost of disposal of hazardous
waste (sludge, etc.)
Summary: Benefits of Tank Cleaning
• Provides operating benefits for some time, which depends on method(s) used.
• Is the surest way to quickly get rid of accumulated sludge in tank.
Summary: Down-side of Tank Cleaning
• Expensive
• Requires extended tank outage
• May have safety concerns for workers
• Generates hazardous waste for disposal
• Not a permanent fix – will have to be done again and again
Bob Tatnall
What are the best answers for sludge, fouling and corrosion in
ULSD tanks?
But First… the “truths” associated with common myths.
Myth 1: ULSD Fuel is ULSD Fuel is unstable,unstable, which which leads to sludge. Therefore, you should add leads to sludge. Therefore, you should add stabilizers to your ULSD fuel to prevent stabilizers to your ULSD fuel to prevent sludge formation.sludge formation.
Truth: ULSD is usually very stable, and Truth: ULSD is usually very stable, and studies have shown that chemical stabilizers studies have shown that chemical stabilizers do little or nothing to stop sludge and do little or nothing to stop sludge and corrosion.corrosion.
Myth 2: Algae Algae are a problem in ULSDare a problem in ULSD
Truth: Algae are microscopic plants Truth: Algae are microscopic plants that need sunlight. Therefore they are that need sunlight. Therefore they are one type of “critter” not found in fuel one type of “critter” not found in fuel systems.systems.
Myth 3: The more rapidly you turn your fuel over, the less sludge and fouling there will be.
Truth: Bacteria are limited in what they can use in the fuel. Turning it over rapidly supplies more food for their growth – and therefore more growth. (Look at how fast fuel filters grow sludge!)
Myth 4: I have my fuel polished and the contractor shows me clean fuel….. Therefore my tanks are clean.
Truth: Clean, filtered fuel does not necessarily mean a clean tank. How did the process remove sludge and water from the bottom of the tank?
Myth 5: Biocides are the answer because, if I kill the Bugs, they can’t cause problems.
Truth: biocides usually can’t penetrate into the biofilm (slime) to reach and kill the harmful bacteria – and, even if they did, they would do nothing to stop corrosion.
Myth 6: If I useIf I use Detection Kits Detection Kits I can detect I can detect Microbes and Fungus Growth. Then I can add Microbes and Fungus Growth. Then I can add Biocides to kill them and the problems will go Biocides to kill them and the problems will go away.away.
Truth: Test kits are a good way to sell biocides, Truth: Test kits are a good way to sell biocides, because they almost always show living critters because they almost always show living critters in fuel. The microbes they measure are free-in fuel. The microbes they measure are free-floaters – most of whom are doing nothing of floaters – most of whom are doing nothing of concern. Kits generally don’t sample the biofilm concern. Kits generally don’t sample the biofilm on the walls and bottom of the tank – and, even on the walls and bottom of the tank – and, even if they did, biocides don’t work there anyway!if they did, biocides don’t work there anyway!
Myth 7: You can use an additive toYou can use an additive to remove all water remove all water from your tanks so bugs from your tanks so bugs can’t grow and cause problems.can’t grow and cause problems.
Truth: While some additives do contain Truth: While some additives do contain alcohols that can “hide” water in fuel, alcohols that can “hide” water in fuel, they do not remove it from the system. they do not remove it from the system. This “wet” fuel is now more corrosive This “wet” fuel is now more corrosive than was water alone (to tanks than was water alone (to tanks andand engines) – and great food for bacteria!engines) – and great food for bacteria!
So, how do we stop sludge, fouling and corrosion in ULSD?
(Thought you’d never ask!)
The Answer: With Dual Filming Amine Technology
The Dual Filming Amines in Fuel Right®:
• Dissolve existing slime into the fuel, where it passes through and burns up harmlessly (i.e. no more old sludge)
• Coats all wetted surfaces in the system to preclude bacterial attachment – thus slime formation (i.e. no new sludge)
• This coating also protects steel and iron against corrosion – even if there is free water present!
And there’s more good news…
• The amines clean injectors and lower fuel surface tension – thus improving atomization and reducing unburned fuel and smoke,
• The amines act as micro-emulsifiers, pulling some of the water present into the fuel as a slight haze – where it goes through and produces a little steam without causing corrosion or other problems,
• The amine film acts as a lubricating film and greatly reduces metal wear in pumps, etc.
In other words,
• Dirty tanks clean up,• Clean tanks stay clean, and• Corrosion of wetted surfaces stops within
days following first treatment – even though the existing sludge takes some time to go away
• Diesel systems work the way they are supposed to!
What Fuel RightWhat Fuel Right®® customers say customers say
1. Easy To Use
2. No Special Handling Requirements
3. Economical
4. Easy to Measure Success 71
Fuel Right – Does it Work?Fuel Right – Does it Work?
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The Battelle Report revisited(raw, unedited version as originally issued by Battelle)
• Tanks tested for “total DNA” = relative amount of fouling
• One with no apparent problems yet tested very high in total DNA
• One treated twice in prior year with well-known biocide tested very high in total DNA
• One treated once 6 months prior with “biocide” [sic] Fuel Right tested very low in total DNA
Questions / Discussion
Bob Tatnall (technical questions) [email protected] (302) 425-4400Dan Jenkins (sales inquiries) [email protected] (813) 877-4665
See also: www.fuelright.com
Thank You!
For More Information About Solving ULSD Problems:
www.fuelright.com
References:•“Simple methods for the investigation of the role of biofilms in corrosion” Bio-corrosion network, Brite-Euram III Thermatic Network
Essential steps of bacterial biofilm formationpasteur.fr
kingtanktechnic.co.uk / shentongroup.co.uk
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