The solid circulation rate is essential for design of pressurized circulating fluidized beds (PCFBs). With increasing pressure from atmospheric pressure to a few bars, the gas density linearly increases with the pressure, which affects the gas–solid flow characteristics. In this work, experiments were performed at room temperature in a cold PCFB apparatus with a riser of 3.3 m in height and 0.05 m in diameter. The solid circulation rate was studied from 20 to 80 kg/(m²·s) under various conditions with increasing pressure from 0.1 to 0.6 MPa and fluidizing gas velocity from around 1.5 to 8.0 m/s for different Geldart B group particles. Most of the conditions were in the flow regimes of core-annulus flow (CAF) only and CAF with a turbulent fluidized bed at the bottom. The trend of the apparent slip factor with the dimensionless slip velocity was similar at different pressures and for different average particle sizes, and it converged to an exponential function. An empirical equation was obtained by fitting the solid circulation rate with the operating parameters (particle transport velocity, particle volume fraction, Archimedes number, and Froude number), which is helpful for design and operation of PCFBs.

固体循环速率对于设计加压循环流化床（PCFB）至关重要。随着压力从大气压增加到几巴，气体密度随压力线性增加，这会影响气固流动特性。在这项工作中，实验是在室温下在立管高3.3 m，直径0.05 m的冷PCFB设备中进行的。固体循环速率从20到80 kg /（m ²·s）在各种条件下，对于不同的Geldart B组粒子，压力从0.1到0.6 MPa增大，流化气体速度从1.5到8.0 m / s左右。大多数情况仅在核心环流（CAF）和底部带有湍流床的CAF的流动状态下进行。在不同压力和不同平均粒径下，表观滑移系数随无因次滑移速度的变化趋势相似，并且收敛于指数函数。通过将固体循环速率与运行参数（粒子传输速度，粒子体积分数，阿基米德数和弗洛德数）拟合来获得经验方程，这对于PCFB的设计和运行很有帮助。