Correlations for mixing energy in processes using Rushton turbine mixer

This study reports the research results on a mixing process using a stirred tank mixer under the action of a rotating magnetic field (RMF). Dimensionless correlations are proposed to predict the power consumption and mixing time for the mixing systems analysed. The results suggest that the mixing behaviour of the experimental set-ups tested may be assessed using the dimensionless mixing energy as the product of the power input and mixing time. In addition, an innovative strategy is proposed on the basis of the synergistic effect of the rotational Rushton turbine and the RMF generator. The values of the dimensionless energy thus obtained were used to compare the mixing process performed by the mixing devices tested. It is shown that the mixing process under the RMF action has significantly higher values of energy consumption than the conventional Rushton turbine. The total energy consumption for the mixing process performed by the RMF mixer may be reduced by concomitant use of a rotational agitator.

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