Abstract A bubbling fluidized bed (BFB) with a continuous feed/discharge of solids was used as a gasifier in a high-density triple-bed circulating fluidized bed (TBCFB). To carry the heat from the combustor to the pyrolyzer/gasifier effectively, a high-density and high solids-mass flux circulating system is necessary. In this study, the gas-solid flow behavior of a BFB with high solids continuous feeding/discharging mass flux was simulated by an Eulerian–Eulerian model incorporating the Lagrangian (discrete phase model) properties of particles as a tracer to analyze particle motion and determine the optimal feeding tube location and diameter. It was observed that a U-shaped track of particles from the inlet to the outlet and double vortices resulted in particle back-mixing and extended particle residence time. According to the results, some feeding-tube design principles were proposed to achieve smooth solids flow and improve the particle residence time in the BFB in solids mass circulating fluxes ranging from 800 to 1200 kg/m2 s.

中文翻译：

---

高固流量三床循环流化床鼓泡流化床气化炉进料系统水动力模拟及优化

摘要 在高密度三床循环流化床 (TBCFB) 中，使用具有连续进/出固体的鼓泡流化床 (BFB) 作为气化器。为了有效地将热量从燃烧器传送到热解器/气化器，高密度和高固体质量通量循环系统是必要的。在这项研究中，具有高固体连续进料/出料质量流量的 BFB 的气固流动行为通过欧拉-欧拉模型进行模拟，该模型结合了颗粒的拉格朗日（离散相模型）特性作为示踪剂，以分析颗粒运动并确定最佳饲管位置和直径。观察到从入口到出口的 U 形颗粒轨迹和双涡流导致颗粒返混和延长颗粒停留时间。根据结果​​，