SurvivalBlog Resources: Liquid Fuels Storage and Transfer

Introductory Note: The following is the first of a series of articles by JWR that will profile some of the thousands of archived SurvivalBlog articles, grouped topically.

Storing and transferring liquid fuels is topic that often comes up in conversations with my consulting clients and in letters from SurvivalBlog readers. There seems to be a lack of knowledge or misinformed voodoo out there in the general public about liquid fuel shelf life, flammability, containers, and how to transfer fuel when the power grids are down. But those questions have all been “asked and answered” in SurvivalBlog, over the course of the past 11 years.

To begin, it is important to understand that the general rule about distilled oil products is: With the exception of LPG, the more highly refined the fraction, the shorter its shelf life.

Let me back up for a moment, and describe how refining works: In its rudiments, at a refinery crude oil gets heated to around 700 degrees Fahrenheit and it transitions to a gas. These heated gasses are ported into the bottom of a distillation column (commonly called a crude tower) and as they move up the height of the column, they cool and at certain levels they can be shunted off into fractions. As the gasses cool—that is, below their boiling points–they condense into liquids. The liquid feedstocks are then shunted off the distillation column at measured port heights. The fractional heights range from heavy “resids” (like asphalt, coke, and tar) at the very bottom, to raw diesel fuel/heating oils fuels in the middle sections, and raw gasoline at the top of the tower. The raw fractions are then processed further to create variously-named fuel products.

Only about 35% of each barrel of oil will naturally becomes gasoline, which is the highest demand product. However, based on the normal volume of sales, to meet the demand for gasoline, in the end about 50% of each barrel needs to become gasoline. To accomplish this, other fractions get re-worked (“converted”) into gasoline. This conversion is done by several methods including reforming, catalytic cracking, and isomerization—which are three different ways to break big molecules into small molecules—with the desired effect in most cases being creating gasoline. The more sophisticated refineries can also do secondary processes like coking, hydrotreating, and hydrocracking.

But to get back to the general rule: Bulk heavy lubricants that don’t have detergents added can be stored almost indefinitely. Moving up the fractions scale, home heating oil and diesel fuel can be stored for 10+ years IF you add an antibacterial growth agent, such as PRI-D. (Yes, there are microbes that can digest diesel fuel!) Farther up the scale you get gasoline which can be stored for only a couple of years before it starts to break down and then tars, gums, and esters become present, eventually making the gasoline unusable. But gasoline additives such as Sta-Bil and PRI-G can greatly extend the storage life, to as much as six or seven years, but only if proper containers are chosen to avoid water contamination. (Typically water contamination happens because of condensation in a container that is not kept 100% full. The more air volume above the gasoline, the greater the risk of condensation.) Contact with oxygen also contributes to the chemical breakdown of the fuel. This is one reason why steel containers are preferable over plastic ones, since plastics are gradually permeable to oxygen. Big temperature swings are also a problem, since that of course contributes to condensation.

Delving into the SurvivalBlog Archives, you will find many articles like these:

Closing Note: You can use our recently improved Search box in the blog’s right hand column to find even more articles. The ones that I’ve linked to are just a sampling.)

-JWR

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