A Loss Control DreamA Tank Full of Money
I recently had the opportunity to give a paper at a School on Hydrocarbon Measurement. Because of the influx of work and the human tendency to procrastinate, things began to build up, and my time was squeezed from all directions. I waited until the proverbial last minute to start my paper. I worked well into the night. I found it hard to put across a simple message that people would understand. Finally I just went home to get some sleep.
When I got home I went straight to bed and was out before you could say “American Petroleum Institute, Manual of Petroleum Measurement Standards".
I awoke in the middle of the night thirsty, and went to the kitchen to get a glass of water. I walked out of the bedroom and straight into the back yard. I thought to myself, “Where is the kitchen?” Did my wife remodel the house today? However, there sitting in the middle of the back yard, was an aboveground storage tank (AST). “How strange”, I thought.
I went back into the bedroom and woke my wife.
I said; “Honey, there is an Aboveground Storage Tank (AST) in the backyard.”
She asked, “Have you been drinking?”
I said, “No, I was unable to find the kitchen.”
She asked me, “Maybe it’s filled with oil? Maybe we’re rich!”
I said, “I don’t know what’s in the AST but I will go check.”
I went to the backyard, climbed to the roof of the AST, and opened the manway. It didn’t smell like petroleum. I couldn’t see any liquid, so I went back into the bedroom to get a flashlight. When I came back and shined the light into the manway, all I could see was money. Lots and lots of money!
I climbed down the tank and ran back into the bedroom.
I told my wife, “The AST in the backyard is full of money!”
She said, “Full of money? Are you sure you have not been drinking?
I said, “Yes, money, and no, I’m not drinking. At least not yet.”
She said, “You are a tank gauging expert, how much money is in the AST in the backyard?”
I said, “Lots and lots of money.”
She asked “How much money? Ten dollars, a thousand dollars? Maybe a million dollars?”
Being an expert in tank gauging, I went back out to the AST in the backyard with a measuring tape. The AST measured 24 feet in height. From the top of the manway to the top of the money it measured 7 feet even.
I went back into the house and told my wife, “We have exactly 17 feet of money.”
She asked, “If all the money was stacked up it would be 17 feet high?”
I said, “No, a lot more than that. It looks to be 17 feet high across the diameter of the tank.”
She asked, “What is the volume of the money in the tank?”
Dumbfounded, I couldn’t answer. She had been paying attention all these years when I was talking about work.
She asked me, “What is the diameter of the tank? Would that be enough information to calculate how much money is in the tank?”
I said, “The AST in the backyard is very similar to tanks that I have strapping tables on at work. I can estimate the amount of money, or the volume of money, by the height and diameter of the AST!”
She then asked me, “How can you tell me the amount of money in the AST if you don’t know what type of money is in the AST? Is it filled with ones? Is it fives or tens? Are their any twenties or fifties? Did you see any hundreds? Have you seen my slippers?”
We then went to the AST for a further look inside.
We looked into the manway. There were ones, fives, tens, twenties and an occasional fifty and hundred.
My wife asked, “What’s this?”
I said, “That is a gauge well for measuring and sampling the product within an AST.”
She said, “Shouldn’t we measure and sample the money here to get an accurate measurement?”
Together we measured the money in the gauge well. It was eight feet from the reference point.
She asked, “Did we lose a foot of money?”
I said, “It could be the extra weight on the roof. Didn’t you notice the roof flexed when we climbed on top of it?”
She said, “What did you say? Are you calling me fat?”
I said, “No, Dear. The tank roof naturally flexes when it is filled. The gauge well is used to provide a reference point not effected by roof movement.”
She said, “That’s what I thought you said.”
We then took a sample from the gauge well. It was fifties, hundreds, an occasional one, and nothing but paper near the bottom.
My wife asked, “How can you estimate the amount of money in the AST if the quality of the product varies with depth?”
I said, “Stratification; I need to think about this one.”
She asked, “How come there is nothing but paper towards the bottom of the tank? Should we subtract that volume? Besides, are you sure we are not losing any money from our tank? The level has gone down a foot. Are you positive there isn’t a leak?”
Just then we saw a fifty fluttering by in the wind. It was followed by bills of all denominations.
She asked, “What’s happening?”
I said, “I think we are suffering from emissions?”
She said, “How much money are we losing from emissions?”
I said, “I don’t know. We need to close the manway and the gauge hatch.”
She quickly did.
We then climbed back down to the bottom of the tank. We were standing there pondering the situation when my wife noticed a pile of money at the base of the tank.
She asked, “Is the money overflowing my tank?”
I said, “No we just measured it. There is still room left within the tank so I don’t think the money is overflowing our tank.”
She asked, “Could my money have expanded?”
Maybe was I dreaming. This was starting to sound familiar.
She asked, “Could there be a hole in my tank?”
I said, “I’m not sure, there could be a hole in the tank.”
She said, “You measured the level of the money, Mr. Tank Gauging Expert, but you still can’t tell me how much money or the volume of money inside my tank!”
Just then I remembered my lullaby, “API Manual of Petroleum Measurement Standards Chapter 3.6 Measurement of Liquid Hydrocarbons by Hybrid Tank Measurement Systems”
As I awoke, my wife was standing there with a cup of coffee.
She asked, “Did you finish your paper?”
I said, “Yes, I think so.”
Moral of the Story:
The product in your tank is money. You can’t get an accurate inventory (volume) by measuring only level and temperature. You need a gauge that provides volume measurement by API/ISO Hybrid Method (Level, Temperature, Density, & Water) and/or Hydrostatic Method (Mass, Density, & Water). A tank gauge that provides both Quantity and Quality (Density stratification, Free water, and Entrained water) measurement of the product. A tank gauge that can also provide other benefits, such as leak detection, hydrocarbon emissions data, redundant overfill protection, protection against over pressuring a tank or pulling (Vacuum) in a tank, etc.
The MTG “Multi-Function Tank Gauge” is the most accurate volume tank gauge on the market for custody transfer, inventory, loss control purposes, and a whole lot more. Only one tank entry and one electrical connection (for both power and signal) is required. It is bottom referenced (standard), with NO moving parts. The MTG self calibrating and self diagnostic.
MTG measures or calculates the following data from the gauge head: Volume, Level, Mass, Multi-point temperature or Average product temperature, Multi-strata density (True density), Average (Reference) product density, Free water, Entrained water, Vapor pressure, Vapor temperature, Atmospheric pressure, Atmospheric temperature, and (optional) leak detection by mass. The MTG provides custody transfer accuracy from a single instrument, using only one installation flange opening, and one wiring and conduit run.
The MTG provides accurate volume by the Hydrostatic Method, as well as, volume by the Hybrid Method. It provides data on the quality of the product (multi-strata density, free and entrained water). The MTG can be used to monitor product quality, i.e., when to blend or heat. It provides data (vapor pressure and vapor temperature) for the calculation of hydrocarbon emissions, monitors inherent gas blanketing of tanks and can generate alarms for vacuum or over pressure of tanks. Because the MTG provides mass calculation, it is capable of accurate leak detection beyond the scope of any level and temperature measurement device.
Remember the lullaby, “American Petroleum Institute, Manual of Petroleum Measurement Standards; Chapter 3.6 Measurement of Liquid Hydrocarbons by Hybrid Tank Measurement Systems” and Chapter 16.2 Mass Measurement of Liquid Hydrocarbons in Vertical Cylindrical Storage Tanks by Hydrostatic Tank Gauging, these are the only two standards for volumetric measurement of Hydrocarbons within a petroleum storage tanks.
After all, you buy and sell petrochemicals by mass (weight) or volume, not by the inch or millimeter!