The supercritical-water fluidized bed(SCWFB)is a reactor for coal and biomass gasification without pollutant emission.We carried out a series of experiments in a SCWFB,and a dual-capacitance probe measurement system w...The supercritical-water fluidized bed(SCWFB)is a reactor for coal and biomass gasification without pollutant emission.We carried out a series of experiments in a SCWFB,and a dual-capacitance probe measurement system was applied to measure the hydrodynamics of slugs,such as the slug frequency,chord length,and rising velocity.Four groups of Geldart-B particles with different mean diameters were fluidized by supercritical water with a system pressure of 20-27MPa and at 410-570℃.The minimum slugging Reynolds number increases logarithmically with Archimedes number and a predicting correlation of the minimum slugging fluidization velocity in the SCWFB is presented:Rems=32908.84 ln(Ar^0.55+260376.65)-410361.90.The relative error of the above correlation was within ±15% and the averaged relative error was 7.5%.The effect of operating conditions on the minimum slugging fluidization velocity is discussed.This research provides useful guidance for scaling-up design and for determining the optimum range of operating conditions in the SCWFB.展开更多
基金supported financially by the China National Funds for Distinguished Young Scientists(No.51925602)National Natural Science Foundation of China(No.91634109 and No.51676158)the National Key Research and Development Program of China(2016YFB0600102).
文摘The supercritical-water fluidized bed(SCWFB)is a reactor for coal and biomass gasification without pollutant emission.We carried out a series of experiments in a SCWFB,and a dual-capacitance probe measurement system was applied to measure the hydrodynamics of slugs,such as the slug frequency,chord length,and rising velocity.Four groups of Geldart-B particles with different mean diameters were fluidized by supercritical water with a system pressure of 20-27MPa and at 410-570℃.The minimum slugging Reynolds number increases logarithmically with Archimedes number and a predicting correlation of the minimum slugging fluidization velocity in the SCWFB is presented:Rems=32908.84 ln(Ar^0.55+260376.65)-410361.90.The relative error of the above correlation was within ±15% and the averaged relative error was 7.5%.The effect of operating conditions on the minimum slugging fluidization velocity is discussed.This research provides useful guidance for scaling-up design and for determining the optimum range of operating conditions in the SCWFB.
