Design of Fine Powder Handling System Enhancing the Circularity of Aluminium Production

Abstract

Hydro Aluminium wants to separate fine powder particles (filter dust) from the process and send them to a specifically built storage silo by a pneumatic conveying line to mix with basement dust and feed back into the main silo. This approach will improve the circularity of the Aluminium manufacturing process; therefore, Hydro would like to investigate the preliminary design steps by analyzing the flow properties of the fine dust and how they may be controlled to develop a trouble-free and reliable handling system. The main objective of this study is to investigate fluidization properties and physical properties of pure particles and pressure drop calculations for given binary mixtures with different mass ratios of filter dust and basement dust and optimization of pressure drop calculations by varying the initial gas conditions while keeping the pipeline dimensions constant. The calculated Umf and Ut values for pure particles based on selected mathematical models were found to be in pretty good line with the experimental values. The pressure drop calculation results show that the pressure drop is not affected by the mixture composition. It depends only on initial gas pressure and initial gas velocity. Initial velocities for all three mixtures can be set to a fixed value because the minimum conveying velocities and choking velocities are almost the same. To help in choosing the proper design parameters for a system it is required to perform pilot testing and validate the parameters.