Experimental investigation of liquid flow shift due to gas cross flow in non-wetted packed beds

An experimental study has been carried out for the gas-liquid two-phase flo w in a packed bed simulating conditions of the gas and liquid flows in the lower part of blast furnace. The localised liquid flow phenomenon in presen ce of gas cross flow, which usually occurs around the cohesive zone and rac eway in blast furnace, was investigated in detail. Such liquid flow is char acterised in terms of liquid shift distance or liquid shift angle that can effectively be measured by the experiments involved in the current study. I t is found that liquid shift angle does not significantly increase or decre ase with different packing depth. This finding supports the hypothesis of t he force balance model where a vectorial relationship among acting forces, i.e. gas drag force, gravitational force and solid-liquid friction force, a nd liquid shift angle does exist. Liquid shift angle is inversely proportio nal to particle size and liquid density, and proportional to square of gas superficial velocity, but is almost independent on liquid flowrate and liqu id viscosity. The gas-liquid drag coefficient, an important aspect for quan tifying the interaction between gas and liquid flows, was conceptually modi fied based on the discrete feature of liquid flow through a packed bed and evaluated by the combined theoretical and experimental investigation. Exper imental measurements suggest that the gas-liquid drag coefficient is approx imately a constant (C-DG(')=5.4+/-1.0) and is independent on liquid propert ies, gas velocity and packing structure. The result shows a good agreement with previous experimental data and prediction of the existing liquid flow model.