In order to determine the solid phase distribution law of UO2 particles during the gas-liquid-solid fluidization process, Fluidization behavior of nickel powder (simulating catalyst) and alumina (simulating UO2 product) in a cold model experiment of a magnetic field-assisted gas-liquid-solid three-phase fluidized bed, with a focus on separation characteristics under magnetic field regulation were systematically investigated. The results show that in the absence of a magnetic field, the axial solid content distribution of alumina particles varies significantly with the gas flow rates (5-40 L/min). Under low gas flow rates (5-20 L/min), a high-concentration deposition zone is formed at the bottom of the bed, and the larger the particle size, the more obvious the deposition effect. Under medium and high gas flow rates (25-40 L/min), large bubbles break to enhance axial mixing, but the solid content at the top is still lower than that at the bottom. Nickel powder shows significant differences due to its high-density characteristics. Fine particles (200-300 mesh) require a gas flow rate of ≥15 L/min to achieve quasi-uniform dispersion, while coarse particles (100-200 mesh) remain deposited at the bottom of the bed even when the gas flow rate reaches 40 L/min. After the application of a magnetic field, nickel particles gradually accumulate in the lower part of the bed as the magnetic field intensity increases, forming magnetic agglomerated "apparent large particles" that are stably deposited near the gas distribution plate, while non-magnetic alumina floats up with the liquid flow. Under the same magnetic field the solid content ratio of nickel powder to alumina to increase from top to bottom, but the ratio drops rapidly with the strengthening of the magnetic field, indicating a significant aggregation effect of magnetic particles. The research results verified the dynamic separation efficiency of magnetic field-assisted fluidized beds for magnetic catalysts and non-magnetic products, clarified the key parameters of gas flow rate, magnetic field intensity and particle matching, and provided theoretical support for the design of continuous reactors in uranium chemical industry.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |