How Ethanol-Blended Gasoline Reaches Your Local Fuel Pump

[Goldstar]

The Manufacture and Distribution of Corn-Based Fuel Grade Ethanol

As of now (2007), there are ~ 110 operating corn-based ethanol plants in the US with 56 more under construction. IA has the most, at 26, with also the most currently under construction, at 13. The greatest concentration is in the midwest (the cornbelt), but ethanol plants can also be found in a few other areas with more new construction in the works. Most midwestern ethanol plants receive their corn locally, via truck, but those farther away also receive shipments via railroad covered hopper cars (each with a capacity of 3,800 bushels).

On arrival, the corn is ground to a powder, then mixed with water and enzymes. The enzymes will break the corn's starch into even-chain sugars, such as glucose and dextrose. The sugars are then mixed with yeast, which breaks them down into CO2 and ethyl alcohol (ethanol). Some plants release the CO2 into the atmosphere while others capture it and ship it out by railroad tank car. The ethanol at this point is only about 13% of the resulting mix and must be distilled, which separates the alcohol from everything else. The remainder is 95% alcohol which is then vaporized and run through a dryer to yield 200 proof fuel-grade ethanol.

Ethanol plants aren't licensed to ship out beverage-grade alcohol so the product must be denatured. A common denaturant is natural gasoline, a byproduct of the natural gas refining process. This is delivered to the ethanol plant using railroad tank cars. The final product is 95 to 98% pure ethanol and ready to be legally shipped to a distribution point.

An additional byproduct of the process ought to be mentioned for the sake of completeness. After the enzymes extract starch from the corn, there are wet, ground up bits rich in proteins, left over; they're called distillers grains and some of it will be sold directly to local farmers for feed. The bulk of it is dried, shipped out by railcar, and sold in distant feed markets.

The Distribution of Gasoline
Virtually all of the gasoline in this country is carried through pipelines from the refineries to distribution centers, commonly called 'tank farms', which are distributed across the country, but mainly located at the edges of big cities to efficiently serve population centers. These tank farms sit astride and tap into pipelines to enable them to collect the gasoline in giant storage tanks. Tank trucks deliver fuel from these tank farms to your local gas station. But it's also at these tank farms that ethanol enters the fuel supply. Therefore, at these locations, separate ethanol storage tanks must be provided to store the alcohol fuel. When a gas station-bound tank truck takes on a load of gasoline, the driver must specify how much ethanol, if any, he wants blended into the fuel. In NJ, as in many other locales, a 10% ethanol blend is mandated. The gasoline and ethanol flow from their respective tanks at the specified blend into the tank truck.

For a variety of reasons, ethanol cannot be transported in existing pipelines. First, gasoline pipelines are directional; they're pressurized and carry their commodity in only one direction. Pipelines currently run from the coasts, where most refineries are located, inland. To build a pipeline system running the other way would be costly (about $1 million per mile). Second, the current pipeline system has large amounts of water that fuels can "skate" on top of; ethanol would absorb the water and leave an unuseable mess behind. Although both these obstacles could be overcome, the solutions would be costly. Consequently, ethanol must be transported by railroad tank car from plant to distribution point where it supplies the separate ethanol storage tank(s).

The largest tank farm in the New York metropolitan area is operated by Motiva Industries, a Shell Oil subsidiary, located at Sewaren, NJ. I've seen this facility from the outside and it's a gigantic operation. The associated truck and railcar activity never seems to end.

Currently, there are no ethanol plants in New England, NY, NJ, PA, MD, or Delaware, but two are under construction in upstate NY along the Canadian border. This may change, however, if the economics start to favor placing the plants closer to large population centers.

Happy Motoring!

[pigeon]

Good read!

[TheMAN]

great... this proves my point that ethanol is the stupidest energy policy in existance... gg's, now we use many times the energy to make fuel for our cars and at the same time run out of corn to eat!

so much for being "environmentally friendly"

[Goldstar]

Originally Posted by pigeon

Good read!

Thanks, Chris.

Originally Posted by TheMAN

great... this proves my point that ethanol is the stupidest energy policy in existance... gg's, now we use many times the energy to make fuel for our cars and at the same time run out of corn to eat!

so much for being "environmentally friendly"

There's no question that the Feds mandate to increase ethanol production drives up the price of feed corn. Since it costs more to feed domestic livestock, this in turn drives up the price of meat and milk, and the price of corn destined for human consumption. Further increases in ethanol production will start to cause scarcity as more and more corn is diverted to alcohol production, rather than being used as a food.

Additionally, since the Feds subsidize ethanol production to keep down the price at the pump, the additional income enjoyed by farmers and distillers such as Archer, Daniels, Midland, comes partially from the American taxpayer.

Also, as Edwin points out, there is considerable controversy as to whether ethanol production results in a net energy gain or loss, throwing into question some of the claimed environmental benefits of this process. One definite benefit, however, is that ethanol serves both as an excellent oxygenate and an octane booster in gasoline, replacing MTBE with its potential to contaminate ground water.

Perhaps our best hope for using ethanol as a practical alternate fuel lies in deriving it from cellulosic feed stocks, although this process is not yet commercially viable.

Happy Motoring!

[zerocover]

I didn't know ethanol was mandated in our fuel now. Ballocks, so theres no way I can ever have a half way efficient car anymore. Shell was carrying normal gas up until this year I think with only sunoco having the crap ethanol blend.

Any state I can still get real gas?

[Goldstar]

Ten percent ethanol blend (E10) is actually a good fuel mix. The alcohol acts as an oxygenate and reduces emissions, while at the same time the naturally high octane rating of ethanol raises the octane rating of the fuel.

Happy Motoring!

[TheMAN]

until there's water in your gas tank

[Goldstar]

Motiva Industries (a subsidiary of Shell Oil) mentioned in post #1, has recently opened another ethanol terminal in Providence, RI. The terminal will blend rail-shipped ethanol into gasoline arriving by pipeline for tanker truck distribution to local gasoline stations. Motiva's sister terminal in Sewaren, NJ is one of the largest ethanol-blending facilities in the US.

Happy Motoring!