Greener with dry ice

First ever dry ice-based engine wash to be introduced

Lufthansa Technik goes even greener: Cyclean® Engine Wash system is already easy on the environment. It minimizes kerosene consumption, reduces pollutant emissions and extends the service life of the engines. But now Lufthansa Technik is going a step further. In the future, engines will be cleaned with dry ice, the solid form of carbon dioxide (CO2). This approach is not only efficient; it also saves water and enables engine washes to be performed at outdoor temperatures below freezing for the very first time. Engines can thus be washed 365 days a year anywhere in the world – even in permafrost regions. 

Since 2007, Lufthansa Technik has been using the specially developed, water-based Cyclean® system to wash engines. More than 90,000 engine washes have been performed at over 40 stations worldwide so far. But that was just the beginning. In 2014, Lufthansa Technik turned its attention to testing alternative cleaning agents and further improving the verification process. Dry ice proved to be the best alternative due to its high cleaning performance. In addition, it is not necessary to generate additional carbon dioxide, since the carbon dioxide used is a by-product of the oil refinery and fertilizer industries.

For the purpose of positioning the system in front of the fan blades, Lufthansa Technik developed a mounting platform with an omnidirectional drive in cooperation with Darmstadt University of Applied Sciences and Imetron GmbH. Featuring wheels on all sides, the vehicle can be driven in any desired direction, enabling the system to be positioned in front of the engine quickly and simply. With the help of the integrated scissor lift, the system can be lifted and lowered as required. This guarantees that all types of engines can be cleaned, no matter how big or high up they are.

During the cleaning process, dry ice pellets are fed into the engine through the intake. Upon impact, kinetic energy is released and some of the dirt is dislodged from the components. The dry ice pellets immediately transform from a solid to a gaseous state without melting in between. Upon contact with the ice-cold pellets (-78.5 degrees Celsius / −109.3°F), the dirt contracts, becomes brittle and is thoroughly but carefully removed. Since dry ice blasting does not leave any residue, no run-up is necessary after the engines have been washed.

There is also no need to fasten any pieces of equipment to the engine. This reduces the time needed for the cleaning process – and thus also the ground time – to just 30 minutes compared with conventional engine washes. An engine wash with dry ice can therefore also be carried out during a short turnaround at the gate.

The test phase with the prototype has been completed successfully, and several patent applications have been filed. Now the Cyclean Dry Ice engine wash system will be developed into a product. As of 2019, the new procedure will be available alongside the water-based Cyclean® engine wash. Lufthansa Technik will then be the first and only company in the world to offer efficient and gentle cleaning of engines with dry ice, thus making another significant contribution to green MRO in the aviation industry.