Estimation of circulation flow rate in RH reactor using water model

The effects of the injecting conditions on the circulation flow characteristics in RH reactor were investigated by the measurements of downward flow velocity in down-leg with a laser Doppler velocimeter and the flow observation with a video camera in water model experiments. The maximum circulation rate and the critical gas flow rate increased with the number of orifices. It was observed that the circulation flow rate took maximum when the injected bubbles reached to the opposite side of the pipe wall (single injection) or collided with the other (multi-injection). By considering the geographical condition, the critical gas flow rate can be estimated with the empirical equations on the bubble diameter and the penetration length of bubbles. The diameter and the number of orifices affect the circulation characteristics of the reactor, because they change the bubble size and the bubble frequency in the up-leg. The optimum operating condition was estimated using the results of water model experiments, which showed that the optimum condition might be changed in each heat because of the erosion of refractories.