Chemical Looping Gasification for Sustainable Production of Biofuels – The CLARA Project

Within the scope of the Horizon 2020 project CLARA, a novel biomassto-biofuel process chain is being developed. The fuel production plant consists of a chemical looping gasifier for the production of a raw syngas, a gas treatment train to provide the required syngas composition for the subsequent synthesis, and a FischerTropsch (FT) reactor to covert the syngas into liquid FT-crude. This crude can then be purified and upgraded to ready-to-use second generation drop-in biofuels in existing state-of-the-art refineries. So far, various oxygen carrier materials were evaluated through lab-scale test regarding their suitability for chemical looping gasification. Ilmenite proved to be the most promising candidate and was therefore selected for further investigations. Successful test campaigns in a small CLG pilot unit supported the findings made in lab-scale units. A novel pre-treatment concept of wheat straw based on pelleting and additivation was developed, which allows for an economic decentralized production and avoids bed agglomeration in a chemical looping gasifier.
Furthermore, a novel sour gas separation concept, allowing for an efficient removal of H2S from sour gases, was successfully tested at lab-scale. Based on the underlying technologies, the project partners derived an optimized process layout of the entire biomass-to-liquid chain, achieving competitive figures for the most important key performance indicators, such as attaining negative CO2 emissions and achieving an energetic fuel efficiency of 55 % for the entire process chain. The full process chain has been demonstrated within four weeks of pilot testing at the Technical University of Darmstadt. Currently, the full-chain BtL concept is being assessed by means of risk studies as well as techno-economic and environmental considerations