This paper presents a method of describing an airlift bioreactor, in which biodegradation of a carbonaceous substrate described by single-substrate kinetics takes place. Eight mathematical models based on the assumption of liquid plug flow and axial dispersion flow through the riser and the downcomer in the reactor were proposed. Additionally, the impact of degassing zone with assumed complete mixing on the obtained results was analyzed. Calculations were performed for two representative hydrodynamic regimes of reactor operation, i.e. with the presence of gas bubbles only within the riser and for complete gas circulation. The conclusions related to the apparatus design and process performance under sufficient aeration of the reaction mixture were drawn on the basis of the obtained results.

This paper presents the development of a multiphase aerodynamic reactor designed for multi-component systems, focusing on precise catalyst dosing in the combustion chamber. The study aims to underscore the significance of this work by emphasizing the critical role of optimized operational conditions in enhancing the transportation of the modifier for combustion processes. Through comprehensive numerical simulations and experimental tests, this research explores the impact of parameters such as flow rates of the dosed substance and air, dosing nozzle outlet diameter, and conduit diameter on the flow rate and trajectory of the transported modifier. The findings highlight the importance of a minimum droplet diameter of 30 μm, preferably 50 μm, for proper delivery to the combustion chamber. This study not only identifies key differences between analyzed structures but also emphasizes the crucial role of these operational parameters in achieving optimal conditions for modifier transport.