Supercritical water (SCW) fluidized bed reactors convert biomass to fuels without pollutants emission. In this work, experimental studies were carried out to investigate voidage distribution in an SCW fluidized bed by capacitance probes. Quartz sands with different particle sizes were fluidized by SCW under system pressure of 20–27 MPa and temperature of 410–570 °C. The effect of operation conditions on voidage distributions of the emulsion phase (e.g. averaged voidage and probability density) is discussed. A predicting correlation between voidage and superficial velocity in emulsion phase is proposed. The relative error of the correlation is within ±25%. These research results provide useful guidance for the optimization of supercritical water gasification technology.

超临界水 (SCW) 流化床反应器将生物质转化为燃料而不会排放污染物。在这项工作中，通过电容探针进行了实验研究，以研究 SCW 流化床中的空隙率分布。在 20-27 MPa 的系统压力和 410-570 °C 的温度下，SCW 对不同粒径的石英砂进行流化。讨论了操作条件对乳液相空隙率分布（例如平均空隙率和概率密度）的影响。提出了乳液相中空隙率和表观速度之间的预测相关性。相关性的相对误差在±25%以内。这些研究成果为超临界水气化技术的优化提供了有益的指导。