J. Raczek

ON THE ENTRAINMENT OF SOLID PARTICLES FROM A FLUIDIZED BED

Abstract This paper presents a generalized approach to the phenomenon of entrainment of solids from a fluidized bed. Starting with the discussion of the transport disengaging height (TDH) and of the elutriation of particles above the TDH, one arrives finally at the relationship between the elutriation rate constant, saturation carrying capacity and choking parameters of pneumatic transport.

Model of gas flow above a bubbling fluidized bed: prediction of splash zone height

Abstract A model of the flow of gas above a bubbling fluidized bed, using the idea of ‘ghost bubble’ motion, has been worked out. The predictions of the model are compared with data from the literature and satisfactory agreement is found. Measurements of particle splash height and model calculations lead to the development of a criterion for the splash zone height. Suitable equations (the first empirical and the second derived from the model) for determination of the splash zone height are proposed.

Investigations of the acceleration region in the vertical pneumatic conveying

It has been shown that pressure drop in the acceleration region can be predicted using the uniform flow model if the proper value of the initial solid velocity is known. The equations for estimation of this value were proposed and the correlations for drag force coefficient and friction factor that give the most accurate results were selected.

Selection of the gas working velocity in vertical pneumatic conveying systems for binary mixtures

Abstract The conformity between calculated and measured velocities which correspond to the minimum pressure drop in vertical pneumatic conveying systems has been used as a criterion for model correctness. The model has been tested for different correlations describing solid particle friction factor, f p . In the case of the correlation for f p according to [9] used in the model the best fit has been obtained