Numerical Simulation On Gas-liquid Two-phase Flow In Fuming Furnace

Fuming furnace is mainly used for treating metal slag, such as lead and zinc, but its investigation is still unsatisfied with production demands. It should be further improved in each part with its design and operation, which needs a comprehensive recognition on injection behavior and the slag pond gas-liquid movement mechanism. Therefore, searching for the distribution of gas phase and gas-liquid movement mechanism of the slag pond is very important to optimize the design of the furnace structure and analyze the deeper reason meeting in the fuming process.In this paper, the single nozzle model was firstly numerically simulated by the VOF and the RNG k-ε, and the configuration changing process of the gas in the slag pond and the spatial distribution of various physical fields was obtained. Then the effect of several parameters on gas-liquid two-phase movement in the slag pond was studied. Finally, the effect of interface chemical reaction on gas-liquid two-phase movement in the fuming furnace was analyzed. The difference between the Euler-PB and the VOF for gas-liquid two-phase movement in the fuming furnace was compared and its reason was analyzed. The main conclusions are as follows:1) Under basic condition, gas distribution in the slag pond changes periodically with time. The pressure decreases gradually when the height increases, and the average speed of the liquid slag is0.632m/s. The lifting gas clearly adheres to the sidewall during side blowing.2) The lower the nozzle is, the faster the slag stirs. The average speed of the liquid slag fluctuates with the nozzle diameter, increasing rapidly as nozzle gas flow rate increases, even can reach0.89m/s for the three nozzles, but with different gas distribution in each central cross-section. It is1.49m/s, while the pond narrows down to0.3m, which is more than twice when pond is1.0m.3)It is consistent that gas changes as time runs, whether the interface chemical reaction has or not. However, if it is, the volume of the gas phase mainstream changes slightly and the average residence time of gas in slag pond is0.22s, while it can strongly reach0.29s when without it.4)Both the Euler-PB and the VOF model make agreement that gas flows upward in the bottom of the slag pond and then move away from the nozzle to the right side near the surface, though the former insists a smooth transition process on its flow path of gas phase mainstream channel and the latter changes dramatically. Pictures48, Tables9, References70...