For Roland Schwarz, things hot up as winter sets in. As Vice President Airport Infrastructure - Airport Facilities and Area Services at Germany’s largest airport in Frankfurt am Main, he must ensure that air traffic flows smoothly—even in adverse weather conditions such as snow, ice, or black ice. In this responsible task he is supported by a team of 450 experienced employees operating a fleet of 243 specialty vehicles. “More than 1,200 aircraft are handled every day in Frankfurt. The take-off and landing runways alone cover an area of 750,000 square meters to be cleared—which corresponds to more than 100 soccer fields. So we need to work quickly and reliably,” he says.
To keep this heavy air traffic moving even in poor weather conditions, take-off and landing runways as well as the adjacent taxiways and aprons are cleared by a convoy of vehicles. “This could consist of up to 21 winter service machines,” says Schwarz. “At the head of the convoy is a service vehicle; this is usually followed by up to 14 snow sweepers, two snowblowers, and three gritting vehicles. Next, a friction tester drives over the surface, testing it for the frictional resistance that is necessary for safe aircraft landing."
The winter service team of Frankfurt Airport needs about 30 minutes to simultaneously clear two take-off and landing runways of snow and ice—a real class act. “This is a conjunction of excellently trained staff, high-end machinery, and the reliable and efficient de-icing agents that we spread on the runways and the entire apron,” says the experienced head of the unit. These must work fast and adhere securely—even at extremely low temperatures.”
Efficient, eco-friendly, and safe
Potassium hydroxide based de-icing agents satisfy all these demanding criteria. At the Ibbenbüren site, in a joint venture with Akzo Nobel, Evonik operates a membrane electrolysis facility producing potassium hydroxide. This potassium hydroxide is sent by ship to the Lülsdorf site, where it is further processed to potassium formate.
The potassium hydroxide, obtained from a potassium salt (potassium chloride), is usually supplied as a 50 percent solution. When this is reacted with formic acid, the product is the de-icing agent potassium formate. Compared with other de-icing products, it works more efficiently on icy runways and has better adhesion.
Evonik’s potassium hydroxide based de-icing agent is biodegradable. “Degradation of potassium formate consumes relatively little oxygen,” explains Hans Put, who heads Evonik’s Potassium Derivatives Product Line. “And the less oxygen that is consumed in wastewater and water bodies, the more environmentally compatible the de-icing agent is."
Proven in practice
Potassium formate has already proven to be an efficient, eco-friendly, and safe de-icing agent at many airports around the world. In Europe it is now regarded as the standard. Roland Schwarz and his team appreciate the value of the product: "It’s helped us out of many tough situations in a very wide range of weather conditions. Even when things looked difficult, we have always succeeded in keeping air traffic on the move."