The numbers tell the story: ethanol is the most used alternative fuel in the United States, and the U.S. is the world’s greatest producer of the commodity. According to the U.S. Energy Information Administration (EIA),
U.S. production of fuel ethanol was 15.8 billion gallons in 2019, the fourth consecutive year that daily production exceeded 1 million barrels. Meanwhile, the Renewable Fuels Association has reported that the U.S. produced 53% of the world’s ethanol in 2020.
What these numbers ultimately mean is there is always a large volume of ethanol working its way through the U.S. fuel-supply chain, and its producers and transporters must honor its unique handling properties. The most obvious of these is that because
of its affinity for water, ethanol cannot be shipped via pipelines, which produce water as a byproduct of their operation.
Therefore, railroads have emerged as the No. 1 shipping source for ethanol. As is the case with all liquid fuels, it is vitally important that proper fuel-handling techniques be practiced in order to prevent fuel contamination. This includes outfitting
the rolling ethanol fleet with systems and components that are compatible with its handling characteristics, with failure to do so resulting in component degradation that can contaminate the fuel or lead to dangerous product leaks.
Specifically, metals that have been shown to degrade over time when in the presence of ethanol include brass, lead, zinc and lead-based solder. Ethanol will also degrade such non-metallic materials as natural rubber, polyurethane, polyvinyl chloride (PVC),
cork, and certain thermoplastic or thermoset polymers.
On the other hand, stainless steel, nickel-plated steel, unplated steel, black iron and bronze are resistant to ethanol degradation, with non-metallic compounds Buna-N, polypropylene, nitrile, Viton®, neoprene rubber and PTFE interacting
well with ethanol.
Recognizing the importance of ethanol in the U.S. motor-fuel realm, along with its eccentric handling demands, Midland, a product brand of OPW, has developed a complete Ethanol Valve Package in which all components are ethanol-compatible while being able
to help mitigate ethanol-handling concerns, along with the potential challenges that can arise if an ethanol railcar is involved in an accident:
Pressure Relief Valves (PRV)
- A-19075 Smart-Flow™: The A-19075 Smart-Flow PRV’s design helps
achieve the right balance between minimizing product loss and tank-car integrity in the event of a railcar accident. Tested against competitive PRVs, Smart-Flow has a 17% longer time-to-failure rating. The Smart-Flow PRV is also designed to lower
the risk of tank rupture, minimize product loss and minimize the amount of lading that remains in the tank car.
- A-22075 and A-22076: These
high-flow PRV models have been specifically designed for use on railcars that transport ethanol. They have a start-to-discharge pressure setting of 75 psig and a certified capacity of nearly 30,000 standard cubic feet per minute (scfm).
Bottom Outlet Plug Valves
- A-549-CS, A-549-XS, A-549-SS and A-549-MO: These valves feature a spring-loaded plug that helps ensure the valve remains closed in the event of a railcar accident. The plug’s triple-seal design provides excellent redundant sealing for long service life, while the cavity-free
interior prevents entrapment and isolation of media inside the valve’s body.
Bottom Outlet Ball Valves
: The valve features live-loaded, adjustable packing through the stem, which results in reduced leak potential. A compact design and universal rigid mounting allow the valve to fit all current API adaptors and vapor fittings,
which results in extended valve life.
Vacuum Relief Valves (VRV)
- A-210/A-212: These VRVs have been designed to allow atmospheric
air to enter and protect the tank car from collapse where there is a vacuum, making them ideal for use on railcars tasked with transporting unique commodities like ethanol. Their no-step design eliminates improper cycling of the valve,
while a built-in debris screen keeps contaminants from entering the valve-seating area.
Magnetic Gaging Devices
The lightweight float and gauge rod, which are available in stainless steel for increased corrosion resistance when used with ethanol, improve durability and performance.
For more information on Midland and its complete portfolio of railcar equipment for the safe, reliable and efficient transport of ethanol and all high-value or hazardous commodities, please visit midlandmfg.com.