There's an old joke that goes: "In any project, the first 90 percent of a job takes 90 percent of the time and the last 10 percent takes the other 90 percent." That could describe the production of fuel ethanol where a great deal of energy is needed to distill it to a concentration of 95 percent and removing that last 5 percent is even more difficult.

Whitefox Technologies has a system that it says will make that final step more efficient, and with some reengineering, make ethanol plant operations more efficient. According to Stephan Blum, Whitefox's chief operations officer, a gallon of ethanol contains about 39 percent more energy than it took to produce. By installing his company's technology, he says ethanol producers can increase that to 81 percent. "As a result of our exchange with industry and very large applications we have right now, we are continuously improving and modifying our technology to match fuel-grade ethanol," Blum says. "We have just begun to implement these improvements. We believe there is a lot more [improvement] possible than that 81 percent."

Whitefox got its start in Europe retrofitting plants that produced ethanol and other chemicals and solvents for pharmaceutical, beverage, cosmetic and other industrial uses. The company has been retrofitting ethanol plants the past five years. It recently began to offer its services in the fuel ethanol market in the United States, where the plants are much larger. "We started developing the technology for high-grade ethanol," Blum says. "Our system was originally designed to dehydrate ethanol to very high purity levels, around 99.95 percent and higher." Fuel ethanol is dehydrated to a purity of 99.6 percent.

Whitefox customers not only report energy savings, but economic savings as well. "Our customers are reporting significant increases in productivity and substantial reductions in costs of production," Blum says. "Both of those things are needed for the industry to be viable in the long term. Producers must realize reasonable returns on their investments and consumers have to have access to fuel at reasonable costs."

According to Blum, these results are achieved by changes made throughout the production system. These changes are only made possible because of the unique characteristics of Whitefox's membrane technology—which offers an opportunity for modifications in both heat integration and energy rebalancing. "In the near-term future, we expect to demonstrate efficiency improvements of more than 400 percent," Blum says.

Proving the Technology
Bruggeman Alcohol (BA) is a German ethanol producer that implemented Whitefox's technology in 2002. The company's plant near Stuttgart produces 5 MMgy of industrial, pharmaceutical, cosmetic and beverage alcohol and was built in 1989 by Lurgi, according to Joachim Hofmann, managing director of BA. "We started with the old plate and frame technology," he says. "We were not very successful with that technology and we closed the plant in 1996. In 1999 we had our first contact with Whitefox."

Whitefox convinced BA that converting the plant to its technology would solve most of the company's production problems. "We did a lot of investigation and said we would try it in a demonstration plant," Hofmann says. "If it ran well, we would continue and increase our capacity. We transferred the data from that plant—which is also Whitefox's demonstration plant—and Whitefox optimized the housings, the modules and improved our technology."

White Fox is currently retrofitting two fuel ethanol plants in the United States and is installing its equipment in two plants under construction. When these projects are completed, they will total more than 500 MMgy of capacity. "We have already started the successful commercialization of our technology in the United States," Blum says.

At the heart of the Whitefox system is its dehydration technology. The company offers dehydration modules that use membrane technology to purify ethanol. "I originally worked with membrane technology when it was in its nascent stage in the 1980s," Blum says. "We had been using the standard technologies that were out there and found that they were technically flawed. So basically we started developing a concept that solved the [technical] issues and was industrially reliable and simple enough to make it a workable technology."

Whitefox offers several sizes of its dehydration equipment. Its modular design allows the company to scale its equipment to match the needs of its customers. "Our modular concept lets us equip very small facilities," Blum says. "We can put the modules on skids so we can increase capacity to accommodate small- and medium-sized customers. Then we have the next larger units, our multi-modules, and we can also put those on skids. Then we have the very large industrial modules."

The modules work by using a membrane material that is particularly permeable to water. "Then you need to create a driving force to remove the water," Blum says. "It is like a sponge that absorbs water and then you have to remove the water from the other side of the sponge. This is how you make it a continuous dehydration."

Each of the industrial-sized modules will produce about 12.5 MMgy, Blum says, and multiple modules can be installed in an ethanol plant to handle a plant's full capacity. "That is the trick of the modular concept," he explains. "Basically you can size your plant in very small increments to the largest production plants."

The technology used by Whitefox is different than the zeolite-based molecular sieves currently used by ethanol producers. "The molecular sieve is a pellet which also absorbs water," Blum says. "But because you have a pellet, it traps the water and gets saturated. This is why you have to have alternating beds. When one gets saturated, the other one becomes active and you have to regenerate [the saturated] bed. That makes the molecular sieve a cyclical process."

Blum says the pressure fluctuations involved with regenerating molecular sieves shortens the life of equipment in ethanol plants. "There is a lot of wear and tear on the valves because the cycle time of a molecular sieve is about three minutes," he says. "So in three minutes you evacuate and pressurize huge vessels. Our membrane doesn't have that. You continuously run it with the feed and it continuously dehydrates so you don't have any cyclic process at all."

Easy to Maintain
According to Peter Tippelt, production manager for BA, much of the efficiencies in Germany came from less maintenance needed for the Whitefox technology. "In the plate and frame technology we had a lot of problems with seals and a lot of leakage," he says. "Also the plate membranes were not stable and they broke. This was very improved [with the Whitefox modules]. There are only two O-rings and the membranes are much more stable. There are no breakdowns in the membranes and the maintenance is much better. With the plate and frame, it was a lot of work to replace the membranes and it was not very efficient. Often when we changed one membrane the other membrane or seal would break. After the maintenance we would not get good results and there would be new leaks."

Maintenance on the Whitefox modules is simple. "To change the membrane, we have cartridges," Tippelt says. "You take out one cartridge, put in another cartridge and close the module. It is much easier to do." Another big advantage of the membrane is that it can dehydrate ethanol feeds as dilute as 50 percent. Blum says molecular sieves can only handle solutions of 92 percent ethanol or higher. This property allows the ethanol producer to choose the percentage of alcohol being distilled that makes the most sense from an energy and economic standpoint. "That means you can dehydrate a lot more efficiently than you can with a molecular sieve," he says. "That has a significant impact on the design of the whole process. You don't have to drive your distillation towers as hard. If you do it right and integrate the technology into the plant you have to rebalance the plant. The energy savings are substantial."

The membrane also tolerates high temperatures of up to 350 degrees Fahrenheit. The polymer membranes can be used at atmospheric, medium and high pressures, which allow them to be adapted for use in all ethanol plants. The regenerate stream—the material removed during dehydration—contains less ethanol than the regenerate streams off of molecular sieves, Blum says. "Our total separation is a lot more efficient," he says.

While Whitefox has been working with European ethanol producers for years, it is a newcomer to the fuel ethanol industry. Part of the company's challenge is to let ethanol producers know what it can offer them. "We haven't yet publicized this technology, maybe it's time to do so," Blum says. "The underlying technology is well-proven. We've worked out all the kinks. We can now say with confidence that this is the technology that will make ethanol the renewable energy source the world is looking for."

Blum sees his equipment as a quantum leap for ethanol producers. He calls it a disruptive innovation as opposed to a sustainable innovation. "A sustainable innovation is the kind that every producer will maintain to remain competitive in their environment," he explains. "They will continuously seek process improvements. But as all competitors do the same thing, they stay at the about the same level. The good ones get better but the bad ones get better too. With disruptive innovation we develop technology that significantly improves the productivity of a competitor so that he can immediately compete with the best practice producers. That is the disruptive effect."

Blum says Whitefox is more than an equipment supplier. He sees the company as a systems integrator. "You will find articles out there that will say the membrane itself will not make that much difference," he says. "Just replacing a molecular sieve with a membrane will be a sustainable innovation. It will make a little bit of difference. But it will be a marginal improvement." Whitefox looks at an ethanol plant's production process and rebalances it to optimize the integration of the membrane modules. This is what produces the energy and economic savings. "Once you know how to properly rebalance the entire plant then you will achieve this disruptive effect," Blum says. "It is not just replacing one system with another. It is integrating and modifying the entire the philosophy of a facility that makes this disruptive effect."

When an ethanol producer enters into an agreement with Whitefox, the company analyzes the plant's production cycle. "We make suggestions for changes and then implement the changes in collaboration with the clients themselves, or with the client's engineering firm or our engineering firm," Blum says. "There are various possibilities. The whole thing is only limited by the availability of engineering capacity right now."

Blum says the ethanol industry is not standing still. With new ethanol plants coming on line every month, the state of the art in production is advancing. In order for existing ethanol producers to remain competitive, they must also be willing to continue to innovate and upgrade their facilities. "The older plants will have to do something in order to compete with these new facilities," he says. "I believe that is the ideal scenario for Whitefox. We are certain, and have demonstrated that we can get old plants to an efficiency level that is comparable to new facilities."

Jerry W. Kram is an Ethanol Producer Magazine staff writer. He can be reached at jkram@bbibiofuels.com or (701) 746-8385.