The dissertation project "RAW - Recovery of inorganic valuable materials from gas generation" aims to make residual materials such as biogenic waste, sewage sludge or industrial residues usable as an urban resource and to make inorganic valuable materials such as phosphorus (P), nitrogen (N), potassium K) and others available.

The aim of this research project is to develop innovative recovery strategies via the process path of thermo-chemical gasification and gas purification in order to efficiently recover secondary recyclable materials for the first time.

The RAW project focuses on optimizing the process and operational management of the two-bed fluidized bed (DFB) process through experimental investigations on a laboratory scale and at a 1 MW demonstration plant in order to maximize the utilization of the inorganic elements.

To this end, samples from the experimental investigations are analysed, characterized and the potential recovery of the individual recyclable materials is evaluated technically and economically. For example, up to 1,500 tons of nitrogen and phosphorus per year can be recovered from the potential recycling of sewage sludge and other waste such as sludge from the pulp and paper industry. This could cover up to 50% of the annual phosphorus requirement in Austria. The project thus makes a significant contribution to CO2 savings and to closing the material cycle in Austria.

The expertise developed as part of the dissertation project opens up new fields of research in the field of gas production and synthesis, which extends the energetic use of fuels to include the recovery of valuable materials from secondary sources. This opens up additional added value for the process, which is becoming increasingly important due to the use of ash-rich and heavily contaminated residual materials.

The theoretical as well as experimental investigations of the topic provide a solid basis for the techno-economic consideration and life cycle analysis, which are also part of the project.