Experimental study of two-phase flows under the composite fluidization of desulfurizer straight/rotating flows in a circulating fluidized bed

The Venturi straight-flow fluidization speed of a circulating fluidized bed desulfurizer will change with a change in boiler load. This has a negative influence on desulfurization efficiency. The authors have come up with a straight/rotating flow composite fluidization mode, which can adapt to boiler load variation. Moreover, a PDA (Phase Doppler Anemometer) measurement system was employed to test the gas-solid two-phase flow field under this kind of fluidization mode. As a result, the gas-solid tangential speed and concentration distribution were obtained under the condition of a change in swirl airflow and an imaginary tangential radius in the circulating fluidized bed. Test results indicate that the tangential velocity in the composite-fluidization circulating fluidized bed will increase with an increase in radius and the gas-solid tangential slip speed is higher than that of the straight flow fluidization. There will also be an increase in concentration in the desulfurizer and a higher intensity in internal circulation, resulting in a corresponding increase in desulfurization efficiency.