异径垂直管道浸取器的流体力学研究

Flow Characteristics of Vertical Tubular Leacher with Different Bore between Up-and Down-flow Tubes

研究了上、下行管具有不同口径的异径垂直管道浸取器的流体力学特性,导出了上、下行管空隙率的计算式和总压力降的模型。试验装置的下行管直径为24mm,上行管直径为24.0,28.9,38.1或47.4mm。当实验用的颗粒物料为55—65目河砂,上行管内液相流速为0.074—1.3m/s,和悬浮液固相体积分率低于0.072时,所有操作都是稳定的。总压力降的模型计算值与实验测定值间的平均相对误差为9.1％。数据分析得出:若保持下行管径而适当扩大上行管径,对降低总压力降和提高颗粒的滞留率都是有用的。

The flow characteristics of vertical tubular leacher with different bore between up-and down-flow tubes were studied. The equations for calculating the voidage in up-and down-flow tubes and the model for estimating the total pressure drop were derived. The pressure drops were measured on experimental set-up with the down-flow tube 24.0mm in dia and various up-flow tube 24.0,28.9,38.1 or 47.4mm in dia. When the sand size is between 55 and 65 mesh, the flowing velocity in up-flow tube is 0.074-1.3 m/s and the volume fraction of solid in suspension smaller than 0.072, all the operation is stable. Results show that the mean relative error in the calculated with determnied pressure drop is 9.1%. It should be pointed out that if the bore of down-flow tube is kept in constant and the bore of up-flow tube is expended suitably, then the total pressure drop could be decreased and the holdup of particles could be increased in the mean time.