Print

Properly Handling Ethanol Throughout the Supply Chain

By Gary Schriever | May 22, 2007
No one knows whether or not ethanoldespite the renewable fuels thresholds set forth in the Energy Policy Act of 2005will ever become the first choice among motor fuels consumers. However, there is no arguing that ethanol, in some form, will continue to be a major player in powering the nation's on-road vehicles.

Whether an oxygenate used in 10 percent doses in regular gasoline or a potential panacea for the country's dependence on foreign oil in its highly concentrated E85 form, the production and consumption of ethanol for fueling purposes continues to rise on an annual basis, as the following 2006 numbers attest.

114 ethanol plants were in operation with a total annual capacity of 5.48 billion gallons at the end of 2006
70 ethanol plants were under construction
Actual production totaled 4.9 billion gallons, up from 3.4 billion gallons in 2004
Ethanol blended into 46 percent of America's gasoline, mostly as E10
Ethanol comprised 3.5 percent of total U.S. gasoline consumption
1,120 gasoline stations (out of 164,476) offered E85
6 million flexible-fuel vehicles (out of 230 million) hit the road

Even the Indy Racing League, which holds the venerable Indianapolis 500, has gone green requiring all race cars to fuel with 100 percent ethanol in 2007, replacing the 10 percent ethanol/90 percent methanol blend used in 2006.

The Infrastructure Question
However, with this increase in production and demand comes a corresponding rise in the questions and concerns surrounding ethanol and its use.

Is the country capable of producing enough corn (the current feedstock of choice) to keep up with ethanol production demands?
When will technology allow alternate forms of feedstock to be economically and commercially viable for the production of ethanol, and by doing so, reduce the demand on corn crops?
Is the infrastructure and equipment in place to handle the production, loading, unloading, shipping, transporting, storing and delivery of ethanol and its derivative productswith all of their unique properties and compatibility issuesto the consumer's gasoline tank or store shelf?

It is with this final question that this article will address. The one area where ethanol material compatibility has garnered some headlines recently is at the business end of the supply chain. Last October, Underwriters Laboratories Inc. (UL) suspended its authorization of E85 dispenser components and said that it would be updating its requirements, citing as a primary concern the potentially corrosive effects E85 could have on dispenser components used at fueling sites.

In March, Sen. John Thune, R-S.D., and 13 other farm-state senators said UL's decision to suspend its authorization of E85 dispenser components was having a "chilling effect" on the installation of E85 fuel pumps at service station locations and that the lack of new pumps could hamper the development of ethanol.

Less than a week after the senators' comments, UL established a timeline for internal testing and validation of E85 equipment, and it will begin accepting equipment for evaluation and certification by the end of 2007.

Corrosion Issues
Companies that produce the hanging hardware and nozzles for fueling operations, are caught in the middle of this. "The UL suspension of all E85-listed products really caught us by surprise," says Les Rogers, product specialist for the dispensing products division of Cincinnati-based OPW Fueling Components. "Especially since we were the first to the market with a UL-approved solution, [and] then to have the approval pulled [it] was definitely unexpected. We spent the time and had the research to support our product approvals. We're convinced our products are designed to meet the demands of E85 service right now."

OPW Fueling Components' research showed that unprotected products made of exposed, soft metals may show degradation when in contact with ethanol. This results in a white, chalky corrosion that could be passed on through the nozzle. However, by developing products that are made up of either nickel-plated or stainless steel components, and ethanol-friendly elastomers, OPW feels E85-dispensing equipment complies with all ethanol-handling recommendations.

Further upstream, there haven't been any headline-grabbing pronouncements or material compatibility issuesjust research and subsequent equipment developments that have helped ethanol products enter the mainstream.

Due to its unique properties, ethanol-blended fuel generally can't be shipped by petroleum product pipelines due to operational issues. This is mainly related to ethanol's affinity for water, which is a byproduct found at some level in all of the world's major petroleum pipeline systems. The ability to ship by pipeline is also limited because there are currently no pipeline networks near the majority of ethanol production facilities. Therefore, a separate distribution system is needed to get ethanol to the point where it is blended into petroleum-based fuel and loaded into tank trucks or railcars for delivery to retail and fleet operators. The costs of building a new pipeline in the United States are also extremely prohibitive with estimates as high as $1.1 million to $1.3 million per mile.

As is the case with all liquid fuels, it is vitally important that proper fuel-handling techniques be practiced to prevent fuel contamination. Certain materials commonly used with gasoline may be incompatible with high-level ethanol blends, causing them to degrade and contaminate the fuel. Metals that have been shown to degrade over time in the presence of high-level alcohol blends include brass, lead, zinc and lead-based solder. Nonmetallic materials that degrade when in contact with ethanol include natural rubber, polyurethane, cork gasket material, leather, polyvinyl chloride (PVC) polyamides, and certain thermoplastic or thermoset polymers.

On the other hand, unplated steel, nickel-plated steel, stainless steel, black iron and bronze have shown resistance to ethanol corrosion, with nonmetallic materials like reinforced fiberglass, Buna-N, Neoprene rubber, polypropylene, nitrile rubber, Viton and Teflon meeting acceptable usage standards with E85.

This inability to ship ethanol by pipeline creates opportunities for tank truck and railcar manufacturers, as well as the companies that manufacture the valves, seals, gaskets, gauges and transfer equipment, such as loading and unloading equipment, for use in these applications. The ultimate responsibility for the safe shipment of ethanol falls on the shipper.

Developing the Answers
"The primary compatibility concern is that while alcohol is easy to handle, when it's denatured with gasoline, you can have problems with the compatibility in the seals," says Kevin Cook, vice president of sales and marketing for Skokie, Ill.-based Midland Manufacturing. "The selection of seals for rail tank car equipment is the responsibility of the shipper, and since they understand what they're shipping better than everybody else, they have the responsibility to identify the correct seals to use. In general, the seals have been very effective. Ten or 15 years ago, there were issues with ethylene propylene diene monomer rubber seals being attacked by the denaturant, but we've learned from those experiences and moved on."

To effectively combat potential compatibility issues with ethanol, Teflon-encapsulated O-rings are being used on plug valves, which can be made of carbon steel with some stainless-steel trim. Elastomer O-rings in pressure-relief valves and vacuum-relief valves are being made from ethanol-resistant Buna or Viton G compounds. The rail tank cars themselves are made with carbon steel.

Railcar or tank-truck loading and unloading processes are another area of concern when it comes to ethanol material compatibility. "We really haven't had any problems," says Dave Morrow, product manager of loading systems for Lebanon, Ohio-based OPW Engineered Systems. "Most bulk plants have specified the use of carbon steel or stainless steel materials of construction with aluminum subcomponents. We have seen some concern over the use of aluminum, but most users don't seem concerned with this material being used as a subcomponent on a loading arm."

As for seal selection, Morrow follows the producer's recommendations and has had great success with Viton GFLT high-grade flourocarbon elastomers (FKM) in ethanol service. With morepolymers ethanol being shipped, the one area where Morrow has seen a significant change is in the flow rates being used to load and unload the fuel. "Many people are wanting to load rail cars at very high rates like 600 to 800 gallons a minute," Morrow says. "That gets you up into six-inch loading arms, which can introduce ergonomic, safety and storage concerns. To safely and efficiently handle arms of that size, we're doing a lot of pneumatic cylinders to assist with maneuvering and counterbalancing the arms."

Another issue with the higher loading rates is the potential for static generation. "We stress the importance of a properly grounded loading system and recommend utilizing a ground verification package to ensure that the system is properly grounded prior to loading," Morrow says.

The other issue that many shippers are faced with is vapor recovery. Most of the ethanol being loaded into tank trucks and railcars is being top-loaded through an open hatch. To address vapor recovery concerns, most loading arms are being equipped with a vapor recovery attachment such as a flat hatch plate or inflatable hatch seal.

Grand Rapids, Mich.-based Blackmer reported seeing some ethanol compatibility problems with the seals on its pumps. About a year ago, the FKM-style fluorinated elastomer seals that Blackmer was using on its various lines of sliding vane pumps began experiencing some leakage. "Our customers were calling and saying, 'Hey, what's going on?'" says Scott Jackson, a product manager for Blackmer. "They were beginning to have leakage that was not acceptable."

After researching the problem and getting together with its O-ring vendors, Blackmer decided to use a higher grade of FKM in the seals that would give them a broader range of compatibility and allow the pumps to be used with all grades and blends of ethanol. Jackson equates it with upgrading from regular unleaded gasoline, which works just fine in your automobile, to super premium for a boost in performance. "Now we have almost a full year of experience with these higher-grade components and have had no further problems," Jackson says. "Since this upgraded FKM has proven very successful, we have standardized to this upgraded material across the board. From now on, any of our pumps that have FKM O-rings will have this new upgraded material."

Blackmer manufactures its pumps in stainless steel, ductile and cast-iron materials. However, Jackson notes that the large majority of its customers are using ductile and cast-iron models that are showing no signs of corrosion after several years of use.

Elsewhere, components appear to be holding up just fine with the various ethanol-handling demands. "On components that we manufacture, we have not seen a great amount of impact," says Chris Gooding, director of sales and marketing for Kansas City, Mo.-based Civacon and Knappco. Civacon manufactures a complete line of overfill equipment, American Petroleum Institute heads, vents and valves used in the transfer and transport of ethanol and petroleum products. Knappco manufactures industrial access ports, manholes, hatches, weld rings and fill covers in dry-bulk applications. Knappco's fill covers, access doors and pressure/vacuum relief vents are used on storage tanks in many ethanol processing plant applications.

"With dedicated ethanol hauling or ethanol-gasoline blends, we haven't really seen any effect," Gooding says. "The products are holding up very well in the ethanol market."

According to Gooding, the biggest hurdle for Civacon has been assuaging the concerns of its customers, who are leery of using older components in newer ethanol-handling operations. "Mainly, we haven't seen any challenges as far as the performance of our products, but we've had to educate our customers who are wondering if the components will hold up," he says. "Our stance is that what you have now will be suitable for an ethanol application; it's just a growing market."

The market has also had to adjust to the different requests going into truck trailer manufacturers. Whereas in the past a typical gasoline trailer made of aluminum would have four different compartments for hauling up to four different formulations of gasoline, some trailers are now being built with stainless steel for the dedicated hauling of ethanol.

While no one knows what the ultimate ethanol level will be in relation to the country's motor-fuel needs, it's apparent that the companies involved in its handling are more than capable of doing the job safely and efficiently. The ethanol market is not brand new. There have been producers and haulers in the United States utilizing standard petroleum equipment in ethanol transport for over 20 years without any real issues or problems. There haven't been any major equipment failures or issues attributed to ethanol transport. This same standard equipment has successfully been used for many years in Brazil, where over 80 percent of the cars sold today can run on gasoline, 100 percent ethanol or almost any blend in between.

Gary Schriever is the market manager for biofuels for OPW Fluid Transfer Group. Reach him at gschriever@opwftg.com or (513) 696-1550.

The claims and statements made in this article belong exclusively to the author(s) and do not necessarily reflect the views of Ethanol Producer Magazine or its advertisers. All questions pertaining to this article should be directed to the author(s).
 

0 Responses

     

    Leave a Reply

    Comments are closed