NISTM New York Storage Tank Conference November 2015 Tank Acidification and the Affect of Dry Nitrogen to Reduce Water Vapor and Oxygen in the Tank Ullage Presenter: Greg Young Vaporless Manufacturing, Inc. gyoung@vaporless.com Gregory Young 06/08/2014
Quality Petroleum Equipment Solutions for Over 25 Years Nitrogen Blanketing Tank Ullage Monitoring 11/03/2015
Nitrogen Blanketing Tank Ullage Monitoring To Stop: Aggressive Corrosion In the Tank In the Sump
To Stop: Nitrogen Blanketing Tank Ullage Monitoring Petroleum Vapor Intrusion PVI Contamination to the ground and structures in the area due to Petroleum Hydrocarbons - PHC s that have been released or escaped from the UST into the surrounding environment.
Nitrogen Blanketing Tank Ullage Monitoring To Reduce Fuel Loss Through Insuring the Tank Ullage is tight and stays tight By blanketing the hydrocarbon with nitrogen
Nitrogen Blanketing Tank Ullage Monitoring Reduce Hydrocarbon Emissions to the Air
Nitrogen Blanketing Tank Ullage Monitoring Stop Moisture Infiltration Prevent air with water vapor from being drawn into the UST; RH = 65% Dry Nitrogen 65% to <2% May float up to 10% when fuel is dropped
Nitrogen Blanketing Tank Ullage Monitoring To Reduce Oxygen content in the UST Ullage
Aggressive Corrosion What it is Not Typical Form of Protection are Not Effective It is not Galvanic Corrosion Sacrificial Anodes Not Effective Impressed Current Not Effective
Aggressive Corrosion What it is Not Phase Separated Fuel
Aggressive Corrosion What it is It is rampant growth of one or more Acetobacter Bacteria cultures It is the waste of the bacterial growth, Acetic Acid and other stronger acids that chemically form
Why Then, Why Now? Ultra Low Sulphur Diesel Different Refining Techniques Different Fuel Stocks Reduction of Water Use Reuse of Water New Fuel Formulations Reduced Sulphur Helped keep bacteria in check Anybody heard of Ultra Low Sulphur Gasoline everywhere in USA by 2017
VMI s Experience In 2006 / 2007 VMI began hearing of corrosion issues, asked to investigate competitors MLLD failures frozen open In 2007 VMI eliminated all red metals, stopped using untreated aluminum Improved steel treatment Introduced stainless steel vent lines By 2008 on all of our product lines converted
Untreated, Mistreated or the Wrong Metal May Be a Problem
While we were monitoring all fuels and all equipment, the EPA and Regulators were seeing and focusing on; Problems in the Sump(s) With Ethanol Fuels
The Conclusion of this Study was: A link exists between ethanol in motor fuels and the corrosion of metals in the sumps of an undereground storage tank.
The Conclusion of this Study was: Acetic acid bacteria (Acetobacter) can use oxygen from the atmosphere to rapidly transform the ethanol to acetic acid. The acetic acid (and other acids formed) will facilitate the corrosion of metals.
While others were worried abot the sump, Some were worried about the inside of the tank, The headspace and the attached equipment. Drop tubes that would not easily pull Submersibles that were difficult to pull High filter use and metal granules Meter wear and replacement Overfill prevention failure Sticking tank probe floats Bungs spinning in fiberglass tanks
Faced with a tank that had corrosion so bad the submersible motor column broke off and fell to the bottom of the tank, then replaced, and rapidly corroded again. The dispensers were replaced, the meters in the new dispensers had to be replaced, tank cleaning was regularly used along with biocide, the corrosion continued. A nitrogen blanket system was installed Note, 2 tanks on site
Copper coupon installed in tank vent 10/15/2013 On 01/15/2014 after 3 months the tape was removed The coupon stayed in the tank for 7 more months without significant corrosion.
Environmental Corrosion Control for Large Fuel Tanks and Reducing the Risk of Explosive Atmospheres These protocols have been a recommended practice and have been proven in use at refineries, bulk fuel storage facilities, bulk fuel transfer terminals, and airports worldwide for over 7 years VMI has Patented and scaled a customized solution for tanks 50,000 gallons and less
How to Reduce / Eliminate the Acidic Attack The bacterial growth is accelerated by the presence of: water and oxygen The Acetobacter Bacteria is everywhere
How to Reduce / Eliminate the acidic attack Keep water / moisture out of the tank Rain Caps for all tanks P/V Valves for all tanks Keep the tank top fittings tight / sealed
Problems Even When the Tank Top is Tight The more successful (higher volume) the site is, the more air that is drawn into the tank Incoming air has moisture Moisture condenses on cool tank interiors Tank top moisture is food for bacteria
Eliminate the Tank Breathing P/V Valve Monitor tank vapor pressure to determine ullage pressure Deliver dry Nitrogen to replace the air drawn into the tank No moisture to condense No oxygen for bacteria
USEPA Recognition of Study National Tanks Conference The USEPA Studied 42 sites The Aggressive corrosion was worse than anticipated Recommendations Keep tank dry Reduce oxygen in headspace of tank
What we have proved Dry Nitrogen Works The retrofit concept is very workable New installations are even easier
Daily Testing of the Tank Top is achievable Monitoring the pressure of the ullage of the tank is achievable. Monitoring the Oxygen content of the Ullage is possible Monitoring the relative humidity in the Ullage is possible Reporting of Alarm status
Daily Testing of the Tank Top is achievable Water ingress due to failure to properly reconnect fittings, probes or other connections is reduced or eliminated. Failure during maintenance or testing to reattach or correctly tighten fittings is identified and communicated.
Reduction of bug kill treatments Premature failure of tank top equipment is significantly reduced or eliminated, including pumps, probes, overfill protection equipment etc. Reduced filter replacements Reduced tank cleans Reduced or eliminated sump failures Reduced or eliminated fill-pipe failures Premature tank failure is reduced or eliminated
Acidification of the Sump 1. Stop the destruction of the portion of the sump you cannot see, inside the tank 2. Stop the transfer of the acidic atmosphere from tank ullage to the inside of the sump
After the Tank Ullage Stops Acidifying, Decaying and Dropping Debris If there has been high filter replacement If meters have been replaced Eliminating Established Colonies A tank cleaning may be recommended
One Byproduct of the Process Nitrogen A constant supply of nitrogen to top off vehicle tires that have nitrogen filled tires We can supply the nitrogen for this at little expense.
New solutions Zane Miller