Ethanol is here to stay. Environmental types insist that it will help keep our water and air clean. Government leaders trumpet its glories as a renewable energy source and a hedge against rising fuel prices. Farmers love it for obvious reasons --subsidies. Now that the leadership in Congress is in new hands, it seems likely that efforts to increase production incentives for ethanol will hasten in the near term.
Once again, sweeping changes are afoot and the fire service is the last to be asked for an opinion. Remember Halon? Likewise, firefighters have been left out of the debate about ethanol. It presents some serious problems for emergency responders. Techniques and resources that have proved effective against hydrocarbon fuel fires such as gasoline will simply not work when applied to a polar solvent such as ethanol. It's as simple as Chemistry 101. This has yet to register with the proponents of putting corn squeezin's in your gas tank.
WHAT IS ETHANOL?
Ethanol is known by many names. To chemists, it is ethyl alcohol or grain alcohol, made by fermenting almost any material that contains starch or sugar. As such, it has always been in demand. Connoisseurs of mountain-made bootleg liquor will know it best as moonshine, white lightning, hooch, fire water or old stump hole. Ethanol weighs in with a 190 proof wallop. Be warned - ethanol made to be used as a fuel is automatically denatured by adding a small amount of gasoline to it, making it unfit for drinking.
About two billion gallons of ethanol are produced annually in the U.S. A bushel of corn processed yields 2.5 to 2.7 gallons of ethanol and various bi-products. The addition of as little as 10 % ethanol to gasoline increases a gasoline's octane by 3 points, which means increased performance. Moreover, ethanol's increased oxygen content ensures that the gasoline burns more completely, thus reducing tailpipe emissions, especially harmful carbon monoxide.
Use of ethanol as a fuel additive is hardly new. During the energy crisis of the 1970s gasoline containing ethanol was marketed as "gasohol." As far back as the late 1800s, ethanol was widely used as lamp fuel. Today, ethanol is already routinely added to gasoline in New York, Connecticut, California and the Midwest, and makes up about a third of the gas sold in the U.S.
Ethanol's new demand stems largely from the decision of many states to stop allowing methyl tertiary butyl ether (MTBE) to be used as an additive in gasoline. MTBE, which can contaminate ground water, makes up about 10 percent of every gallon of gasoline with which it is blended. More than 200,000 barrels of MTBE are consumed per day in the U.S. As per toxicity alone, MTBE is not classified as a hazard for the environment. But because it acts as an emulsifier, MTBE increases the solubility of other harmful components of gasoline, such as the known carcinogen benzene. Plus, even in small quantities, it makes water taste bad.
Unlike MTBE, ethanol reportedly does not pollute ground water. Ethanol blends reduce carbon monoxide emissions, making it beneficial in parts of the U.S. that exceed EPA air quality standards, particularly in winter months.
As fuel, ethanol is primarily used in two forms. E-10 is a blend of 10 percent ethanol with 90 percent unleaded gasoline. In this form it can be used in any vehicle. E-85 is 85 percent ethanol blended with 15 percent unleaded gasoline. In this form it can only be used in specially built vehicles. This means that ethanol can be found in quantities of 10 to 85 percent in gas pumps and 95 percent pure with five percent gasoline added in rail cars, tank trucks and barges.
The U.S. EPA's newly established Renewable Fuel Standard requires nearly three percent of gasoline sold this year to be produced from renewable fuels such as ethanol, with a doubling by 2012.
Please note - because ethanol absorbs water it is highly corrosive to steel, meaning it can not be put into steel pipelines. It is estimated that if 10 percent of ethanol was blended with every gallon of gasoline used in the U.S., it would put about 4,000 truckloads of pure ethanol on the road every day.
ETHANOL ON FIRE
Whether blended with gasoline or not, ethanol is highly flammable. Ethanol burns different from gasoline. On the bright side, it is an almost smokeless fire. Unlike alcohol, it has a red visible flame. On the not so bright side, pure ethanol has a flash point of only 55 degrees F. Add 15 percent water and the flashpoint rises to 68 degrees F. Diluted down to a 24 percent solution, ethanol has a flash point of 97 degrees F, so it is still flammable.
At 10 percent, ethanol is still combustible. That means that if you had a spill involving a 100,000 gallon tanker you could dilute it with as much as 900,000 gallons of water and still have a fire hazard. Good luck finding that kind of water. Other than a small spill on the highway, diluting ethanol is out. Picking up that small spill with absorbent materials designed for hydrocarbon is likely to be difficult too. The ethanol may be left behind as if it were water.
Dealing with ethanol on fire involves using an ATC (alcohol type concentrate) foam specifically designed for polar solvents. Straight AFFF and protein foam will not work. A fire department with an extensive stockpile of the wrong kind of foam would be on the same footing as the poorest rural VFD equipped with no more than fire axes and good intentions.
Even with the right kind of foam, fighting a polar solvent fire is no cake walk. I remember a burning 160-foot diameter storage tank in Texas City. Even with a foam blanket six to eight feet deep, flames were still visible. It took four days to bring that one under control.
How much ATC foam will you need in addition to your standard stockpile? Using ATC on an ethanol fire will require double to four times the amount of foam used to extinguish a gasoline fire of the same size. That makes it not only a matter of expense but logistics. Fixed systems for loading racks and storage tanks may have to be converted to handle alcohol resistant foam. Further complicating the issue is the lack of a standard application rate for ATC. Some brands are .25 gpm, some are .3 gpm and so on. The only way to be sure is to check with the foam manufacturer.
Forget about bioremediation, fire foam that degrades harmful or hazardous materials into less harmful or benign components. Ethanol kills the bugs that eat the bad stuff.
How 'green' is this new environmental wonder fuel? Is it a hazardous material? Is it a biodegradable waste? I have not gotten a straight answer on that yet. MTBE was originally embraced as a gasoline additive as having a benign impact on local air quality. With the problems that developed later, it would seem a hard look at this aspect of ethanol is in order. Yet, I know of one 2,000 gallon spill of ethanol where the environmental agency advised responders to just wash it down the stream. Nothing is that safe anymore.
If it does accidentally flow into a waterway, there is no effective way of collecting it either. Stretching a boom across a river might catch gasoline on the surface, but ethanol dilutes in water, remember.
If the ethanol is ignited, the track record of extinguishing large quantities of it is not real good. The most recent incident of note was in October when 23 cars of an 86-car train derailed in New Brighton, PA. Among the burning wreckage were nine cars of ethanol. Since 2000, there have been at least 26 major fires in the U.S. involving polar solvents, of which 14 were ethanol plant fires and three were ethanol tanker fires. In addition there have been six train derailments, five with fires. Polar solvent tank fires have been reported in Sydney, Australia; Bayonne, N.J. and Texas City, TX. In almost every case, those tanks burned to the ground.
Industrial firefighters and their municipal fire fighting partners need to take a long, hard look at their ability to deal with burning ethanol. About 3.6 billion gallons of ethanol were produced last year in the United States. Events such as New Brighton show that although ethanol is still a relatively small percentage of the fuel used in the U.S. that percentage is growing. The chance of firefighters encountering an ethanol fire is increasing every day. Firefighters will have to be increasingly savvy about the peculiarities of this additive to protect themselves and others. With the right foam in the right system and the right training, we may learn to deal with ethanol as just another typical work day challenge. o