Particles, particle aggregates, and reactor walls complicate the dynamic microstructures of circulating fluidized beds (CFBs). Using local solids concentration data from a 10-m-high and 76.2-mm-inner-diameter riser with FCC (Fluid Catalytic Cracking) particles (d_p = 67 μm, ρ_p = 1500 kg/m³), this paper presents an improved denoising process for use before nonlinear chaos analysis. Using the soft-threshold denoising method in the wavelet domain with experimental empty bed signals as base data to estimate the denoising threshold, an efficient denoising algorithm was proposed and used for the dynamic signals in CFBs. Analysis shows that for the local solids concentration time series, high-frequency fluctuations may be one of the system properties, while noise interference can also make a low-frequency contribution. An exact denoising method is needed in such cases. The correlation dimension and Kolmogorov entropy were calculated using denoised data and the results showed that the particle behavior in the CFB is highly complex. Generally, two correlation dimensions coexist in a low-flux CFB. The first correlation dimension is low and corresponds to small-scale fluctuations that reveal a high-frequency pseudo-periodic movement, but the second correlation dimension is high and corresponds to large-scale fluctuations that indicate multi-frequency movements, including particle aggregation and breakage. At the same axial level, the first correlation dimensions change slightly with radial position, and the main tendency is high at the center but slightly lower near the wall. However, the second correlation dimensions show large changes along the radial direction, are again high in the core region, and after r/R ≥ 0.6 (r as radial position, R as radius of the riser), the dimensions clearly drop down. This indicates that the particle behavior is more complex and has higher degrees of freedom at the center, but clusters near the wall are restrained to some degree because of wall effects.

颗粒，颗粒聚集体和反应器壁使循环流化床（CFB）的动态微观结构复杂化。从10米高和76.2毫米内径提升板与FCC使用本地固体浓度的数据（流化催化裂化）的颗粒（d _p  = 67微米，ρ _p  = 1500公斤/米³），本文提出了一种改进的去噪过程，可用于非线性混沌分析之前。利用小波域的软阈值去噪方法，以实验空床信号作为基础数据，估计去噪阈值，提出了一种有效的去噪算法，用于CFB中的动态信号。分析表明，对于局部固体浓度时间序列，高频波动可能是系统特性之一，而噪声干扰也可能导致低频影响。在这种情况下，需要一种精确的降噪方法。使用降噪数据计算了相关维数和Kolmogorov熵，结果表明CFB中的粒子行为非常复杂。通常，在低通量CFB中两个相关维度共存。第一相关维数低，对应于揭示高频伪周期运动的小尺度波动，但是第二相关维数高，对应于指示多频运动的大尺度波动，包括​​粒子聚集和破裂。在相同的轴向水平上，第一相关尺寸随径向位置而略有变化，并且主要趋势在中心处较高，而在壁附近处较低。但是，第二相关维数显示沿径向方向的较大变化，在核心区域再次较高，并且之后 包括颗粒的聚集和破裂。在相同的轴向水平上，第一相关尺寸随径向位置而略有变化，并且主要趋势在中心处较高，而在壁附近处较低。但是，第二相关维数显示沿径向方向的较大变化，在核心区域再次较高，并且之后 包括颗粒的聚集和破裂。在相同的轴向水平上，第一相关尺寸随径向位置而略有变化，并且主要趋势在中心处较高，而在壁附近处较低。但是，第二相关维数显示沿径向方向的较大变化，在核心区域再次较高，并且之后[R / [R  ≥0.6（[R作为径向位置，- [R作为提升管的半径），其尺寸明显地降下来了。这表明粒子行为更复杂，并且在中心具有较高的自由度，但是由于壁效应，壁附近的簇在一定程度上受到限制。