Intensified Gas–Liquid Mixing in a Quench Box under the Driving of Supergravitational Swirling Flow

To enhance the gas–liquid mixing efficiency of the quench box in a hydroprocessing reactor, a novel structure based on supergravitational swirling flow was proposed. To reach supergravitational flow, the Froude number of liquid in the horizontal swirling tube should be greater than unity. Through computational fluid dynamics (CFD) simulation and using a high-speed camera, the supergravitational swirling flow was visualized. Based on the Higbie’s penetration theory, CFD simulation was conducted to estimate the gas–liquid mass-transfer coefficient, and was compared with the oxygen absorption experiment. It shows the gas flow rate plays a key role in the gas–liquid mixing performance in the quench box. Experiments were also carried out to investigate effects of operating condition on the pressure drop of the two-phase flow in quench box, and a correlation was proposed accordingly.