关键词: 喷动流化床, 最大喷动压降, 二组分混合颗粒, 非球形颗粒, 预测关联式

Abstract: The maximum spouting pressure drop (Δpm) is one of the important parameters for the design and operation of the spout-fluid bed. Almost all the literature correlations for predicting the Δpm were developed from single-component particles or spherical particles, and hence were with some limitation in actual application. In view of this, with binary particle mixtures, single-component spherical particles and non-spherical particles as experimental materials, the Δpm was studied based on a rectangular spout-fluid bed with cross section of 200 mm×20 mm, height of 1600 mm and conical base angle of 60°. The results showed that the Δpm increased with the static bed height, particle density, particle sphericity and deposition component ratio, and decreased with the fluidized gas velocity. While with the increase in particle size or spout nozzle size, it went down firstly and then up with a minimum pressure drop. For non-spherical particles and binary particle mixtures, the variation of total pressure drop with superficial spouting gas velocities was found to be similar with that of single-component spherical particles, while the fluctuation range of total pressure drop was larger under the same conditions. Based on the 854 sets of measured data by experiments, a predicting correlation of the Δpm was proposed by dimensional analysis method, which was in good agreement with the measured data in this work and the experimental data in literature.

Key words: spout-fluid bed, maximum spouting pressure drop, binary particle mixtures, non-spherical particle, prediction correlation