A considerable amount of synthetic resin is used in bonding the blade shells for the rotor blades of modern wind turbines, which can be up to 115 meters long. For the automated meter, mixing and application of the mostly highly viscous pastes, TARTLER has been equipping the industry with the modular multi-component systems of the NODOPOX type for more than three decades. In the recent past, the German company has also expanded its portfolio to include vacuum-based degassing systems. It offers rotor blade manufacturers an innovative solution for significantly reducing the use of resources and materials in synthetic resin processing. In particular, the use of the TAVA 200 F vacuum system in combination with the new inliner squeezing device from TARTLER – a type of roller press – sets standards in the establishment of sustainable processes. This is because the unwanted air voids can be removed from leftover material in the foil bags (inliners) of the drums. This way you can reuse normally scrapped material and lower-waste in production. Olav Davis gives concrete numbers: “Currently around 500 kg of resin paste are used to bond a single rotor blade for wind turbines in the 4 or 6 megawatt class. The material is pumped into the dosing and mixing system primarily from standard 200-liter drums. Until now it has been proven that – even with carefully emptied drums – up to 14 kg of flawless adhesive paste remaines in every drum or inliner. This had to be disposed of as hazardous waste.” Recovering this “lost” material is not only advantageous for the environment, but also to reduce material cost. Thinking of the total amount of material drums used in a yearly blade production, the return of investment for the TAVA system is very short.
Disturbing air as a process obstacle
In addition to the material residue in the inliner, you can also recover material from the process. For example, you need to drain a certain amount of material each time you change a drum to remove the unwanted air that you don’t want to enter the machine. It is also common practice when operating a metering and mixing system to control the mixing ratio on a regular basis. All this extra material, which is normally wasted, can be recovered for the process, as this material is not contaminated and not mixed together.
The TAVA 200 F degassing station and the new inliner squeezing device from TARTLER solve these problems. They make it possible to degas the collected residual material and free it from all air pockets, so that it can be used again safely and trouble-free in the dosing, mixing and application systems. “With a TAVA 200 F, a synthetic resin user not only takes a significant step forward in realizing sustainability goals on the way to zero waste production; it also reduces its operating and material costs. This is because it can increase the usable amount of resin by up to 6.0 percent per 200-liter drum. Depending on the annual paste consumption, the investment in a TAVA 200 F will quickly pay off,” says Olav Davis.