单回路循环流化床的压力平衡研究

为保证流化床装置正常运行,循环回路必须有一个适宜的压力平衡关系。在Φ800 mm×12 000 mm流化床装置上,用多点压力测量仪对固体颗粒单循环回路各部分的压力分布进行了实验研究。结果表明,颗粒单循环回路的压力平衡与装置的运行状态、颗粒的循环量密切相关。整个颗粒的循环回路压力曲线呈“8”字形分布,上部流化器内的压力高于料腿内的压力,下部流化器内的压力低于料腿内的压力。流化速度增大可使颗粒的循环量增加。流化器和料腿内空隙率沿高度的变化趋势是上部大下部小。循环回路的压力分布取决于流化器和旋风管的性质。

Study on pressure balance in a single-loop solid circulation fluidized-bed system

The relation of pressure balance must be kept properly in a circulation loop for keeping a fluidized-bed unit in working order.The pressure balance of a single-loop solid circulation system was experimentally studied in a gas-solid fluidized-bed test facility with the diameter of 800 mm and the height of 12?000 mm by multi-point pressure detector.It is shown that the pressure balance is in close relation with the fluidized bed operation status and solid circulation rate.The measured pressure curve of the whole loop takes the shape of "8".In the upper dilute region of the fluidized bed,its pressure is higher than that of the dipleg,while in the lower dilute region of the fluidized bed,its pressure is lower than that of the dipleg.With the increase of fluidization velocity,the solid circulation rate increases.The distributions of voidage in fluidized bed and dipleg are both trending upwards on the top and downwards at the bottom.The distribution of pressure in a single loop depends on the properties of fluidized bed and cyclone.