To investigate the influence of the fuel characteristics on the conversion behavior in a chemical‐looping combustion facility, lignite coal dust (d90,3=233 μm) and two fractions of bituminous coal with different particle sizes (fine fraction d90,3=163 μm, coarse fraction d50,3=707 μm) were used as solid fuel. To improve the conversion performance, a pilot plant with a rated power of 25 kW was constructed with a two‐stage fuel reactor. The influence of the fuel composition, particle size, and the presence/absence of elemental oxygen on the conversion in the fuel reactor are presented. The used oxygen carrier was produced by the impregnation of γ‐alumina oxide with copper oxide, which is able to release gaseous oxygen, but loses this ability because of deactivation. The lignite dust shows a very good conversion performance and carbon capture efficiencies over 95 % as well as oxygen demands below 2 %. Both bituminous coal fractions have a good performance with regard to fuel conversion and oxygen demand but they suffer from a high carbon slip. Hence the carbon capture efficiency is around 60 % for the fine fraction and 40 % for the coarse one. The performance improvement as a result of the second stage was investigated separately, and we proved that it enhances the overall conversion. In addition, the oxygen carrier generated a favorable reaction environment by releasing elemental oxygen in the second stage of the fuel reactor.

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The production of catalysts such as zeolites is a complex multiscale and multi-step process. Various material properties, such as particle size or moisture content, as well as operating parameters—e.g., temperature or amount and composition of input material flows—significantly affect the outcome of each process step, and hence determine the properties of the final product. Therefore, the design and optimization of such processes is a complex task, which can be greatly facilitated with the help of numerical simulations. This contribution presents a modeling framework for the dynamic flowsheet simulation of a zeolite production sequence consisting of four stages: precipitation in a batch reactor; concentration and washing in a block of centrifuges; formation of droplets and drying in a spray dryer; and burning organic residues in a chain of rotary kilns. Various techniques and methods were used to develop the applied models. For the synthesis in the reactor, a multistage strategy was used, comprising discrete element method simulations, data-driven surrogate modeling, and population balance modeling. The concentration and washing stage consisted of several multicompartment decanter centrifuges alternating with water mixers. The drying is described by a co–current spray dryer model developed by applying a two-dimensional population balance approach. For the rotary kilns, a multi-compartment model was used, which describes the gas–solid reaction in the counter–current solids and gas flows.

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