Multilayer ceramic-based plasma system for the efficient treatment of polluted wastewater

Fraunhofer IKTS develops multilayer ceramic-based plasma systems that ignite plasma using dielectric barrier discharge (DBD), enabling efficient and chemical-free treatment of environmentally critical wastewater and process water. The plasma generates highly reactive oxygen and nitrogen radicals in the water, which lead to the oxidative degradation of persistent pollutants. This allows various residues found in water, such as those from medications (including diclofenac), industrial and household chemicals (including the corrosion inhibitor benzotriazole and PFAS), or agriculture (including the pesticide mecoprop), to be efficiently removed. 

LTCC technology allows the compact integration of interdigital electrodes and microstructured gas channels in a stackable design with high chemical, thermal, and electrical resistance. Miniaturized gas bubbles created by tiny gas channel sizes of 30 µm increase the reaction surface in the water.

A special LTCC process has been developed for the production of such plasma structures, whereby functional patterns with structure sizes ranging from 30 × 30 mm² to 200 × 200 mm² can be manufactured. Measurements on DBD test structures show ignition voltages in the range of 2.8–4.3 kV (at 5 kHz), with smaller electrode distances leading to lower ignition voltages.

Technichal specifications
 

• Reactor type DBD (dielectric barrier discharge) with interdigital electrodes in LTCC
• Substrate material LTCC multilayer
• High chemical, thermal, and electrical resistance
• Structure size 30 × 30 mm² to 200 × 200 mm² (according to design rules)
• Ignition voltage (Ui): 2.8–4.3 kV (at 5 kHz)
• Breakdown voltage (Ud): 6.7–12 kV (safe operation below Ud)

Services offered
 

• Custom ceramic plasma cells (DBD-LTCC)
• Evaluation of degradation performance for customer-specific waters on a laboratory scale
• Data report and scale-up concepts
• Pilot module design and manufacture